Otdr User Guide

User Manual for Handheld Optical Time-domain Reflectometer

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Before using the manual, you should be familiar with the following routines:

Warning Indicating potential dangerous conditions: if no preventing measures were taken, death or severe personal injuries may be caused. Only after completely understanding and complying with the operation conditions, can the operation be carried out. Notice (1) Indicating potential dangerous conditions: if no preventing measures were taken, slight or moderate damage may be caused. Only after completely understanding and complying with the operation conditions, can the operation be carried out. (2) Indicating potential dangerous conditions: if no preventing measures were taken, device damage may be caused. Only after completely understanding and complying with the operation conditions, can the operation be carried out. Important Prompt Involving various disregardful information relating to products. 2

Contents 1. Safety Information............................................................................................................................................................................ 6 1.1 Laser Safety Information........................................................................................................................................................ 6 1.2 Electrical Appliance Safety Information................................................................................................................................ 7 2. Introduction to OTDR.......................................................................................................................................................................9 2.1 Fundamental Principles of OTDR.......................................................................................................................................... 9 3. Product Introduction....................................................................................................................................................................... 12 3.1 Main Functions..................................................................................................................................................................... 12 3.2 Performance Parameters....................................................................................................................................................... 14 3.3 Keyboard Introduction..........................................................................................................................................................15 3.3.1 Single key introduction......................................................................................................................................................16 3.3.2 Compound operation of keys：.........................................................................................................................................17 3.4 LED Panel Instruction.......................................................................................................................................................... 18 3.5 Head Plate Introduction........................................................................................................................................................ 19 4. Menu............................................................................................................................................................................................... 20 4.1 OTDR 【Measure】 Menu................................................................................................................................................ 21 4.2 OTDR 【Analyze】 Menu.................................................................................................................................................22 4.3 OTDR 【File】 Menu........................................................................................................................................................23 4.4 OTDR 【System】 Menu.................................................................................................................................................. 24 3

4.5 Trace Display Interface.........................................................................................................................................................27 4.5.1 Trace Window.................................................................................................................................................................... 29 4.5.2 Event List........................................................................................................................................................................... 31 4.6 Settings of OTDR................................................................................................................................................................. 32 4.6.1 Cleaning and Connecting Optical Fiber............................................................................................................................. 32 4.6.2 Trace naming...................................................................................................................................................................... 33 4.7 Measuring Optical Fiber in “Automatic” Mode...................................................................................................................35 4.8 Measuring Optical Fiber in “Manual” Mode....................................................................................................................... 38 4.9 Measuring Optical Fiber in “Real-time” Mode....................................................................................................................47 4.10 Measuring Optical Fiber in “High Sampling Resolution” Mode.......................................................................................49 4.11 Analyzing Traces and Events..............................................................................................................................................51 4.11.1 Opening Trace Files..........................................................................................................................................................51 4.11.2 Trace Display and Event Table Description..................................................................................................................... 52 4.11.3 Positioning Event in Trace Display and Event List......................................................................................................... 53 4.11.4 Displaying Trace Setting Parameters............................................................................................................................... 53 4.11.5 Amplifying or Shrink Trace..............................................................................................................................................54 4.11.6 Analyzing or Reanalyzing Trace...................................................................................................................................... 55 4.12 Analyzing Result Manually................................................................................................................................................ 56 4.12.1 Acquiring Event Distance.................................................................................................................................................56 4.12.2 Acquiring Event Loss....................................................................................................................................................... 57 4

4.12.3 Acquiring Attenuation...................................................................................................................................................... 58 4.13 Managing Trace Files......................................................................................................................................................... 58 5 Equipment Maintenance.................................................................................................................................................................. 61 5.1 Equipment Routine Maintenance......................................................................................................................................... 61 5.2 Charging the Battery.............................................................................................................................................................62 5.3 Recalibrating Equipments.....................................................................................................................................................64 6 Fault Diagnosis................................................................................................................................................................................ 65 6.1 Frequently Asked Questions.................................................................................................................................................65 6.2 Please Contact Technical Support........................................................................................................................................ 66 6.3 Transportation....................................................................................................................................................................... 66 7 Guarantee......................................................................................................................................................................................... 67 7.1 General Information..............................................................................................................................................................67 7.2 Responsibilities.....................................................................................................................................................................68 7.3 Exceptions.............................................................................................................................................................................68

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1. Safety Information 1.1 Laser Safety Information .

Warning Please never install or terminate optical fiber when light source is in active state. Never peep at the load signal optical fiber to protect your eyes at all time.

Warning If the following designated operational regulations can’t be followed to control, adjust and execute the operation and maintenance process, dangerous radiation exposure may be caused.

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1.2 Electrical Appliance Safety Information If there is need to make sure outage of equipments are outage thoroughly, please pull up the power line and take out the battery.

Warning  External power source can only be used indoors.  Places that equipments positioned should have free circulation of surrounding atmospheres.  Any electric tools used near inflammable gas or in smoke can produce great threaten to safety.  To avoid electric shock, equipments can’t be operated if there is any damage at any surface part (top cover, face plate etc.).  Only authorized personnel can perform electrified debugging, maintenance or repair to running equipments.  Please don’t replace any assembly if cable and battery have been connected.  Even the power supply has been switched off, the capacitance in equipments still might be electrified.

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Equipment Rated Value Temperature

Relative Humidity Power Supply

Operating temperature

0°C to 50 °C

(32 °F to 122 °F)

Storage temperature

-40 °C to 60 °C （-40 °F to 140 °F）

Equipment

0% to 80 %, no condensation

Power supply adapter

0% to 80 %, no condensation

Rated value

100 V to 240V (50Hz/60Hz) maximum input current is 2 A 表 1.2 Equipment Rated Value

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2. Introduction to OTDR OTDR can provide the inside view of the optical fiber and can calculate the length, attenuation values, breakaway point, total return loss and fusion point, connection point and total loss.

2.1 Fundamental Principles of OTDR OTDR sends the short pulse of light into the optical fiber. Due to the interrupt factors such as connector, weld point, bending and faultage, light scattering happens in the optical fiber. OTDR will immediately detect and analyze the signal of backward scattering. Because of the special time intervals, measure the signal strength and use the signal strength to express the event features. OTDR uses the following formula to calculate the distance:

In which: c = velocity of light in vacuum (2.998 x 108 m/s); t = time delay between the emission of pulse and the receipt of pulse; n= refractive index of optical fiber in test (appointed by the manufacturer)，OTDR uses the function of Rayleigh scattering and Fresnel reflection to measure the optical fiber conditions, but the power of Fresnel reflection is thousands times of the backward scattering power. When the pulse is transmitted downwards along the optical fiber, and some small changes in the materials (such as changes and discontinuity in reflectivity) cause the light to scatter in all directions, the Rayleigh scattering will occur. However, the phenomenon that a small amount of light directly reflects back to the transmitter is called backward scattering. When the light transmitted downwards along the optical 9

fiber accouters sudden changes in material density, it will have Fresnel reflection, changes in material density may occur in the joint point or breaking point of the gap. Compared with Rayleigh scattering, Fresnel reflection will reflect a considerable amount of light. The reflection strength depends on the change degree of the refractive index.

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Figure 2.1 OTDR system frame 11

3. Product Introduction 3.1 Main Functions 

Characteristics  Handheld portable type, convenient, favorable cost and performance ratio  Ultra-strong user-friendly type: one-key for all testing  High-capacity data storage  Real-time measuring mode and average measuring mode  VFL visible fault location function, perfect match with OTDR  USB port offers the access to the data uploading  Compatible with the Bellcore GR196 file format  Smart battery capacity indication and alarm function of low voltage of battery  Continue working time for more than 10 hours, especially fit for the long time field application  Dustproof, humidity-proof and shock proof design, necessary to the field applications  Firm and easy for use  Curve sampling mode OTDR application program provides the following curve sampling modes:  Automatic: automatically calculate the length of the optical fiber, set the sampling parameters and acquiring the curve and display the event list and the acquired curve.  Manual: provide all tools for executing the whole OTDR measuring, and the users can control all 12



 

measuring parameters. Real-time: measure the optical fiber in real time, and then compare the results with the previously acquired and analyzed reference curves. It will help you reach the purpose of the time saving when measuring a large amount of optical fibers. High sampling resolution: provide higher range resolution, but the test may be slower.

Post-processing of data You can install the trace management software on the computer to check and analyze the curves without using

OTDR. You can also visit more functions, such as:  Customize the printout  Batch printing  Convert the curve to Telcordia format.

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3.2 Performance Parameters Refer to the OTDR CALIRATION CERTIFICATE.

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3.3 Keyboard Introduction

Fig 3.3 Keyboard

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3.3.1 Single key introduction No. 1. 3. 5. 7. 9. 11. 13. 15.

Keyboard

Functions Turn on/off the instrument Turn on/off the real-time measuring mode Enter/exit the menu Exit the current operation or menu The second functional key Open the stored measuring trace Movable benchmark moves left, menu operation Upturning of event list, menu operation

No. 2.

Keyboard

Functions Turn on/off the operation mode of visible light source: continuous, 1Hz

4. 6. 8. 10. 12.

Turn on/off the average measuring mode Switch AB benchmark Menu operation, determination Global display of trace Store the measured trace or store the altered trace

14. 16.

Movable benchmark moves right, menu operation Down-turning of event list, menu operation 16

17.

Display the information of trace parameters

18.

3.3.2 Compound operation of keys： Mainly used in the quick operation of zoom in and zoom out of curve analysis. No.

1. 3. 5.

Compound keyboard

Functions The trace zooms out transversally The trace zooms in transversally The trace displays globally

No.

Compound keyboard

2. 4.

Functions The trace zooms in vertically The trace zooms out vertically

6.

Table 3.3.2 Instructions of Compound Keys

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3.4 LED Panel Instruction Instructions of indicator lights: No.

1. 3.

Indicator light

Functions Equipment start Start of visible light source

No.

2.

Indicator light

Functions Battery charging

4.

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3.5 Head Plate Introduction

Fig 3.5 Schematic Diagram of Head Plate Warning: Never install or terminate the optical fiber when the light source is in active state. Never peep directly at the load signal optical fiber to protect your eyes at all time.

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4. Menu Menu includes: OTDR 【Measure】 menu, OTDR 【Analyze】 menu, OTDR 【File】 menu and OTDR 【system】 menu. As shown in the following figure. 【Operation】 Menu (【Measure】 Menu)

 Press【Menu】key, enter the menu, and enter【Measure】 menu by default  Press 【 】 and 【 】 keys to select the configuration item 】 to confirm, and press 【ESC】 to exit  Press 【

Figure 4.1 Menu (【Measure】 Menu)

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4.1 OTDR 【Measure】 Menu No.

Item

Functions

Default

Remarks

1.

Range

Set the measuring distance based on the demand

Auto

Auto/500m/1.3km/2.5km/5km/10km/20km/40km/80km /120km

2.

Pulse Width

Set the width of the output pulse of the laser

Auto

10ns/20ns/50ns/100ns/300ns

3.

Avg. Time

Length of the measuring time of the OTDR average mode

30s

Gears: 15s/30s/1min/2min/3 min

4.

Wavelength

Current operation wavelength of OTDR laser

Wavelength measured last time

Gears:1310nm/1550nm/1490nm/1625nm

5.

IOR

Set the index of refraction for the optical fiber waiting to measure

1.4666

The value is generally provided by the manufacturer of optical fiber

6.

Scat. Coef.

Set the back scattering coefficient for optical fiber

-52.1dB

The value is generally provided by the manufacturer of optical fiber

7.

Load Default

The instrument returns to the state as delivered

[Note]: Details of OTDR 【Measure】Menu operations are shown: OTDR Manual Testing Operation

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4.2 OTDR 【Analyze】 Menu 【Operation】 【Analyze】 Menu  Press 【Menu】 key, enter the menu  Press 【 】 and 【 】 keys to select “Analyze” option  Press 【 】 and【 】keys to select the configuration item  Press 【 】 to confirm, and press 【ESC】 to exit

Figure 4.2.2 【Analyze】Menu

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4.3 OTDR 【File】 Menu 【Operation】 【File】 Menu  Press 【Menu】 key, enter the menu  Press 【 】 and 【 】 keys to select “File” option  Press 【 】 and【 】keys to select the configuration item  Press 【 】 to confirm, and press 【ESC】 to exit

Figure 4.3 【File】 menu

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4.4 OTDR 【System】 Menu 【Operation】 【system】 Menu  Press 【Menu】 key to enter the menu  Press 【 】 and 【 】 keys to select “System” option  Press 【 】 and 【 】 keys to select the configuration item 】 to confirm, and press 【ESC】 to exit  Press 【 【 Note 】 For specific operations, refer to the following description.

Figure 4.4 【System】 menu

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1. Select the operation language

Figure 4.4.1 Language Selection

2. Set LCD contrast

3. Set the date and time

Figure 4.4.2 Contrast Adjustment

Figure 4.4.3 Date and Time

【Operation】 Language selection

【Operation】 Contrast adjustment

【Operation】 Date and Time

 Enter OTDR 【System】 menu

 Enter OTDR 【System】 menu

 Enter OTDR 【System】 menu

 Press 【

 Press 【

 Press 【

】 and 【

】 and move

the cursor to 【Language/语言】  Press 【

】 and enter language

selection setting, as shown in figure  Press 【

】 and 【

language, press 【

】 to select 】 to confirm,

and press 【ESC】 to exit

】 and 【

】 and move the

cursor to【Contrast】  Press 【

】 and enter contrast setting,

as shown in figure  Press 【 】 and 【 】 to select proper intensity, press 【 】 to confirm and press 【ESC】 to exit

】 and 【

】and move the

cursor to 【Time】  Press 【

】 and enter date and time

setting, as shown in figure  Press 【 】 and 【 】 to select month, date, hour, minute or second. Press 【 】 and 【 【

】 to adjust the values, press

】to confirm, press【ESC】to exit 25

4. Set power auto off

5. Set Length Unit

Figure 4.4.4 Power Auto Off 【Operation】 Power Auto Off

Figure 4.4.5 Length Unit 【Operation】 Length Unit

 Enter OTDR 【System】 menu

 Enter OTDR 【System】 menu

 Press 【

 Press【

】 and 【

】keys, move the cursor to 【Power Auto

Off】  Press 【

 Press 【 】 enter 【Power Auto Off】 setting, as shown in

figure  Press 【 】 and 【 】keys to select “On” or “Off”, press 【 】 to confirm and press 【ESC】 to exit

】and【

】keys, move the cursor to【Length Unit】

】 and enter 【Length Unit】 setting, as shown in

figure  Press 【 【

】 and 【

】 keys to select the length unit, press

】 to confirm and press 【ESC】 to exit

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4.5 Trace Display Interface As shown in figure, the divisions of all functional areas of the main measuring interface are as follows:

 

① Miles of each grille in laterally; Number of dB of each grille longitudinally The values change with the zoom in and out of the trace windows, and cannot be changed ② Current trace parameters 27

 

③ ④



⑤



⑥

The instrument display only displays: measuring range, measuring wavelength, and measuring pulse width. For detail information, press 【 .】keys. Dump energy of the battery Trace window Trough this window, it can display the measuring trace, and through the trace, reflect the features of the optical fiber link. Refer to 4.5.1 Trace Window. AB benchmark information Distance, loss and attenuation coefficient between AB benchmark Event list. See Event List Operation Refer to 4.5.2 Event List.

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4.5.1 Trace Window

<1> AB benchmark Benchmark instruction: benchmark number + benchmark distance, the distance of the start position of the measured optical fiber, such as: B:32.624km

【Operation】AB benchmarks switch 29

Benchmark switch: press 【

】 key, AB benchmarks automatically switch, the characters of the selected benchmark is deepened.

Benchmark operation: Press 【 】 and 【 】 keys to move the benchmark 【Association instructions】 Move AB benchmarks, 【benchmark information】 will subject to changes

<2> Icon of event types No. 1

Marks

Meanings Start terminal of the measured optical fiber

2

Reflection event

3

Attenuation event

4

Gain event

5

Termination terminal of the measured optical fiber 30

4.5.2 Event List

【Operation】 Check the event list Press【 】 and 【 】keys, and leaf through each event 【Association instructions】 When leafing through the events, the benchmark move toward to the event

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4.6 Settings of OTDR 4.6.1 Cleaning and Connecting Optical Fiber Important prompt:  Make sure to have the maximum power and prevent to have false readings: please clean the terminals of the optical fiber according to the following instructions all the time, and then insert it into the port. We will undertake no responsibilities for the damage or error caused by false cleaning or operation mode of optical fiber.  Please make sure the connected optical fiber has correct connector. Unmatched connector connected will damage the optical fiber and the instrument 【Operation】 Optical cables are connected with the terminals:  Clean the optical fiber terminals according to the following operations:  Use the free swab dipped into isopropyl alcohol to wipe slightly the optical fiber terminal.  Use compressed air to dry completely.  Visually check the optical fiber terminals to make sure it is clean.  Carefully aim the connector to the port to prevent the terminal of optical fiber touching the external part of the terminal or have friction with other surfaces. If the interface of the connector has convex shape fixed design, please make sure to insert correctly into the corresponding groove of the port when connecting. 32

Push the connector in, make the optical cables fix at the correct position and guarantee sufficient contact. If the connector has screw bushing, please screw down the connector to fix the optical fiber at the correct position. Please never over-screw down the connector, or it will damage the optical fiber and the port. Note: if the optical fiber is not aligned completely and/or connected, it will have serious loss and reflection. 

4.6.2 Trace naming After measuring the curve each time, press 【

】, it will pop out the following menu (Figure 4.6.2): 【Instructions】  Every time the device is turned on, it shall reset the trace file name. 【Automatic naming】  After the setting of trace file name is finished at the same device start, it can automatically name the trace files. Such as: if the first file is named as “aaa” when starting the device, when measuring the fiber next time, the trace name will automatically change to “aaa_001”. This function is convenient for measuring the ribbon optical fiber.

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【Operation】 Trace naming 

Press 【



Press 【 】 and 【 】 keys, and move the cursor from right to left, and press 【 】 and 【 】 keys to move the cursor from up to down, and press 【 】 to confirm After finishing the selection of document name, move the cursor to 【OK】, and press 【 】 to confirm If the characteristic is subject to false selection, move the cursor to 【Delete】, and press 【 】 to confirm If there is need to capitalize the letter, move the cursor to 【Caps】 and press 【 】 to confirm Press 【ESC】 to exit or move the cursor to 【Cancel】, exit the main interface.

   

】 key, see Figure 4.6.2

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4.7 Measuring Optical Fiber in “Automatic” Mode “Automatic” mode will automatically estimate the optical fiber length, set the sampling parameters, acquire the curves and display the acquired curves. In automatic mode, you can directly set the following parameters:  Wavelength  Average time  Index of Refraction (IOR) and back scattering coefficient (Scat.Coef)  Non-reflection threshold, reflection threshold and termination threshold For all other parameters, except the parameters that shall be analyzed after the measuring all the time, the application program will use the parameters defined under the “manual” mode. If there is need to modify the other parameters, please transfer to “manual” mode to set specifically. Under “automatic” mode, the application program will automatically set the sampled parameters as optimum according to the current situation of the optical fiber link connected to the equipment. Other optical fibers connected in the same optical cable will use the same test. When beginning to test another link, it can reset these parameters. After the evaluation is finished, the application program will start to acquire traces. The display of traces will continuously be upgraded. 【Operation】 Measure the optical fiber under “automatic” mode 1) Correctly clean the optical joint and the optical connector 35

2) Connect the optical fiber to OTDR port

Notes: There are two ports of OTDR and VFL on the instrument, and please correctly connect to the OTDR port. Warnings Please never connect the optical fiber with light load signals to OTDR port. Any outsourced light signals will influence the OTDR measuring, and high-strength light signals may bring permanent damage to OTDR.

3) Press 【 4) 5) 6) 7)

】 key and select “Range” in “Measure” menu, press 【

】 key to enter range selection window

and select “auto”, at this time, Pulse Width option changes to “auto” Set the average time, for details, refer to the setting of “average time” in measuring parameters in 4.8 Set wavelength, for details, refer to the setting of “wavelength” in measuring parameters in 4.8 Set refractive index and back scattering coefficient, and for details, refer to the setting of “index of refraction” and “back scattering coefficient” in measuring parameters in 4.8 Set non-reflection threshold, reflection threshold and termination threshold, for details, refer to the setting of “non-reflection threshold”, “reflection threshold” and “termination threshold” in measuring parameter setting in 36

4.8 8) Press【

】 key to start the measuring. Press【

】 key again to stop the measuring and analyze the

trace; or press the 【 】 key to start the measuring, and during the measuring process, pressing 【 】key can stop at any time and analyze the trace 9) Press 【

】 key to store the trace Note: When storing the document, it shall prevent duplication of name of the document, otherwise, after the new document being stored, the original document will be replaced by the new document.

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4.8 Measuring Optical Fiber in “Manual” Mode “Manual” mode can provide all tools for the manual execution of the whole OTDR test and measuring, and the users can control all test parameters. In “manual” mode, you can select all applicable test wavelengths by default. 【Operation】 Measure the optical fiber under “manual” mode 1) Correctly clean the optical joint and the optical connector 2) Connect the optical fiber to the OTDR port

Notes: There are two ports of OTDR and VFL on the instrument, and please correctly connect to the OTDR port. Warning: Please never connect the optical fiber with light load signals to OTDR port. Any outsourced light signals will influence the OTDR measuring, and high-strength light signals may bring permanent damage to OTDR.

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3)

Set distance range: corresponding to the distance range of the span of optical fiber to be measured determined based on the measured unit 【Note】 The change of distance range will change the applicable setting of the pulse width. 【Operation】 Set distance range  Press【

Figure 4.8.1 Setting of Distance Range

】key, refer to Figure 4.1

 Press 【 】 and【 】keys, to move the cursor up and down to “Range”  Press 【 】 to confirm, and it will appear the menu in Figure 4.8.1  Press 【 】 and 【 】 keys to move the cursor up and down to the required distance, and press 【 】 to confirm.  Press 【 ESC 】 to exit to Menu interface (refer to Figure 4.1)

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4)

Set pulse width: corresponding to the tested pulse width. Longer pulse allows detecting farther distance of the optical fiber, but the resolution is lower. Shorter pulse width provides higher resolution, but the distance range is smaller. 【Operation】Set the pulse width  Press 【

Figure 4.8.2 Set Pulse Width

】 key, see Figure 4.1

 Press 【 】 and 【 】 keys to move the cursor up and down to “Pulse Width”  Press 【 】 to confirm, and it appear the menu in Figure 4.8.2  Press 【 】 and 【 】keys to move the cursor up and down to the required pulse width. Press 【 】 to confirm  Press【ESC】to exit Menu interface (See Figure 4.1)

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5) Set the average time Corresponding to the duration of average time. In general, longer average time can create cleaner curves (especially to the long distance curves), that is because along with the lengthening of the average time, more noise will be averaged off. Such an averaging process can increase the Signal-to-Noise (SNR) and the ability of OTDR to detect small event. 【Operation】 Set average time  Press 【

Figure 4.8.3 Set Average Time

】 key, see Figure 4.1

 Press 【 】 and 【 】 keys to move the cursor up and down to “Avg. Time” 】 to confirm, and it appears the menu in  Press 【 Figure 4.8.3  Press 【 】 and 【 】 keys to move the cursor up and down to the required time, and press 【 】 to confirm  Press 【ESC】 to exit to Menu interface (see Figure 4.1)

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6)

Set the measuring wavelength: select the working wavelength of laser during measuring 【Operation】 Set the laser wavelength  Press 【

Figure 4.8.4 Laser Wavelength

】 key, see Figure 4.1

 Press 【 】 and 【 】keys to move the cursor up and down to “Wavelength” 】 to confirm, and it appears menu in Figure  Press 【 4.8.4  Press 【 】and【 】keys to move the cursor up and down to the required wavelength, and press【 】 to confirm  Press 【ESC】 to exit to the Menu interface (see Figure 4.1)

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7)

Set the index of refraction and the back scattering coefficient It can convert the measuring time to distance by utilizing the index of refraction (also referred to as group coefficient). Therefore, the knowledge related to the correct index of refraction is crucial to all OTDR measuring (event position, attenuation, regional length and total length etc.) related to the distance. The index of refraction is provided by the manufacturers of optical cables or optical fibers. The test application program establishes a default IOR value for each wavelength. User can set the IOR value of each applicable wavelength. Before each test, it shall check such information. Back scattering coefficient represents the backward scattering amount of the special optical fiber. The back scattering coefficient is used to calculate the event loss and the index of refraction, and this coefficient is generally obtained from the manufacturer of the optical cables. The test application program establishes a default coefficient for each wavelength. The user can set the back scattering coefficient of each applicable wavelength.

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【Operation】 Set the index of refraction  Press 【

Figure 4.8.5 Set the index of refraction

】 key, see Figure 4.1

 Press 【 】 and 【 】keys to move the cursor up and down to “IOR” 】 to confirm, and it appears the menu in  Press 【 Figure 4.8.5  Press 【 】 and 【 】keys to move the cursor to change the digits, press【 】and【 】keys to change the values up and down to the required value, and press 【 】 to confirm  Press 【ESC】 to exit to the Menu interface (refer to Figure 4.1) 【 Note 】 The operation of back scattering coefficient is the same as the index of refraction.

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8)

Set the non-reflection threshold, reflection threshold and the termination threshold By utilizing the OTDR, it can set the pass/non-pass threshold parameters for the test. Apply the set loss, refractive index and attenuation threshold to all events that can measure such values. The setting of these thresholds allows to neglect the event with lower given value, or to make sure to detect all events (even though measuring very small events) 【Operation】 Set non-reflection threshold  Press 【

Figure 4.8.6 Non-reflection Threshold Setting

】 key, see Figure 4.1

 Press 【 】 and 【 】 keys and select “Analyze”  Press 【 】 and 【 】keys to select “NRef. Thre.”  Press 【 】 to confirm, and it appears the menu in Figure 4.8.6  Press 【 】 and 【 】 keys to change the digits, press 【 】and【 】keys to change the digits up and down to the required values, and press 【 】 to confirm.  Press 【ESC】 to exit to the Menu interface (see Figure 4.1) 【 Note 】 The reflection threshold and termination threshold are similar to the non-reflection threshold. 45

9)

Press 【

】 key to start the measuring, and during the measuring process, pressing the 【

】 key

again can stop at any time and analyze the trace. 10) Press 【

】 key to store the trace

Note: When storing the document, it shall prevent duplication of name of the document, otherwise, after the new document being stored, the original document will be replaced by the new document.

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4.9 Measuring Optical Fiber in “Real-time” Mode “Real-time” mode is used to look over immediately the change in the detected optical fiber. In such mode, the SNR of curves are lower and the curves are continuously refreshed, not averaged, until you press the “stop” key. 【Operations】Measure the optical fiber under “real-time” mode 1) Correctly clean the optical joint and the optical connector 2) Connect the optical fiber to OTDR port Note There are two ports of OTDR and VFL on the instrument, and please correctly connect to OTDR port. Warning Please never connect the optical fiber with light load signals to OTDR port. Any outsourced light signals will influence the OTDR measuring, and high-strength light signals may bring permanent damage to OTDR. 3) 4) 5) 6)

Set distance range, and for details, refer to the setting of “distance range” in measuring parameters setting in 4.8 Set pulse width, and for details, refer to the setting of “pulse width” in the measuring parameters setting in 4.8 Set average time, and or details, refer to the setting of “average time” in the measuring parameters setting in 4.8 Set wavelength, and for details, refer to the setting of “wavelength” in the measuring parameters setting in 4.8 47

7)

Set the index of refraction and back scattering coefficient, and for details, refer to the setting of “index of refraction” and “back scattering coefficient” in the measuring parameters setting in 4.8 8) Set the non-reflection threshold, reflection threshold and termination threshold, and for details, refer to the setting of “non-reflection threshold”, “reflection threshold” and “termination threshold” in the measuring parameters setting in 4.8 9) Press 【 】 key to start the measuring; press【 】 key again to stop the measuring and to analyze the trace 10) Press 【 】 key to store the trace Note When storing the document, it shall prevent duplication of name of the document, otherwise, after the new document being stored, the original document will be replaced by the new document.

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4.10 Measuring Optical Fiber in “High Sampling Resolution” Mode “High sapmpling resolution” mode is used to check the distance sampling resolution. In this mode, the distance resolution will be higher; if it is disabled, the measuring will be faster. The high sampling resolution mode is disabled by default. 【Operations】Measure the optical fiber under “high sampling resolution” mode 1) Correctly clean the optical joint and the optical connector 2) Connect the optical fiber to OTDR port Note There are two ports of OTDR and VFL on the instrument, and please correctly connect to OTDR port. Warning Please never connect the optical fiber with light load signals to OTDR port. Any outsourced light signals will influence the OTDR measuring, and high-strength light signals may bring permanent damage to OTDR. 3) Set distance range, and for details, refer to the setting of “distance range” in measuring parameters setting in 4.8 4) Set pulse width, and for details, refer to the setting of “pulse width” in the measuring parameters setting in 4.8 49

5) Set average time, and or details, refer to the setting of “average time” in the measuring parameters setting in 4.8 6) Set wavelength, and for details, refer to the setting of “wavelength” in the measuring parameters setting in 4.8 7) Set the index of refraction and back scattering coefficient, and for details, refer to the setting of “index of refraction” and “back scattering coefficient” in the measuring parameters setting in 4.8 8) Set the non-reflection threshold, reflection threshold and termination threshold, and for details, refer to the setting of “non-reflection threshold”, “reflection threshold” and “termination threshold” in the measuring parameters setting in 4.8 9) Press 【 】 key to start the measuring; press【 】 key again to stop the measuring and to analyze the trace 10) Press 【 】 key to store the trace

Note During storing the document, it shall prevent duplication of name of the document, otherwise, after being stored, the original document will be replaced by the stored document.

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4.11 Analyzing Traces and Events 4.11.1 Opening Trace Files

Figure 4.11.1 Opening Trace Files 【Operation】 

Press 【

 

Press 【 】 and 【 】 keys to move the cursor up and down to select the trace file Press 【 】 key to open the trace file

】 and it shows the following interface, as shown in Figure 4.11.1

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4.11.2 Trace Display and Event Table Description

Figure 4.11.2 Trace Display 【Instruction】 For detail operations and instructions, refer to 4.5 Trace Display Interface By pressing 【 】 and 【 】 keys, you can check each event in the event list; When you change the event, the benchmarks will automatically move to the current event.

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4.11.3 Positioning Event in Trace Display and Event List Under the interface of Figure 4.11.2, you can press 【 event list.

】 and 【

】 keys to check and locate each event in the

4.11.4 Displaying Trace Setting Parameters Under the interface of Figure 4.11.2, press【Info.】 key, it will display the detailed trace parameters, as shown in the Figure 4.11.3.

Figure 4.11.3 Setting Parameters for the Current Trace 53

4.11.5 Amplifying or Shrink Trace The equipment can zoom in or zoom out the trace by operating the compound keys. No.

Compound keyboard

Functions

No.

Compound keyboard

Functions

1.

The trace zooms out transversally

2.

The trace zooms in vertically

3.

The trace zooms in transversally

4.

The trace zooms out vertically

5.

The trace displays globally

6.

【Operation】 Rapidly check the event  Press 【 】 and 【 】 keys, and you can rapidly find out the event you want to check in the event list, and at this time, the benchmarks have arrived at the event  Through the compound key operation, it can rapidly zoom in or zoom out.

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4.11.6 Analyzing or Reanalyzing Trace After opening the trace window, you can enter 【Analyze】 menu and select【Analyze trace】 to re-analyze the trace. If the trace is not ideal though analysis, it needs to re-set the following parameters, and press【Analyze】 key again to reanalyze the trace. The test parameters that can be set are as follows:  Non-reflection threshold  Reflection threshold  Termination threshold The setting modes are shown in the setting of manual setting in 4.8. The test parameters that cannot be set are as follows:  Working wavelength  Measuring time  Pulse width  Distance range etc.

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4.12 Analyzing Result Manually 4.12.1 Acquiring Event Distance OTDR test application program automatically calculate the event position and display this distance in the event list. It can also manually retrieve the event position and the distance between events and it can also display different associated power readings. 【Operation】  Press 【 】 and 【 】 keys to move the benchmark, as shown in figure, first move benchmark A to the position of event 2 

Press 【

】 key to convert benchmark

B; move benchmark B to position 4; at this time, the information list of benchmarks AB contains all information between AB. For details, refer to 4.5.1 AB Benchmarks

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4.12.2 Acquiring Event Loss The event loss (unit: dB) are calculated by measuring the decrease of signal level in the Rayleigh back scattering (RBS) caused by the event. The event loss can be caused by reflection and non-reflection events. 【Operation】  Press【 】and【 】keys to move the benchmark, as shown in figure, first move benchmark A to the point of intersection of straight line 1 and broken line 2 

Press 【

】 key to convert benchmark B; Move benchmark B to the point of intersection of straight

line 3 and broken line 2; at this time, the information list of benchmarks AB displays the event loss.

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4.12.3 Acquiring Attenuation The attenuation measurement of two points can get the attenuation of Rayleigh backward scattering level that can be obtained the same as calculating the distance between the two selected points (unit: dB/km). Only use these two points to calculate and there is no averaging, 【Operation】  Under the trace interface, move the benchmark A to the position of any point 

Press 【

】 key, and move benchmark B to any point.

Note: There should be no events between markers A and B when performing the two-point attenuation measurement.

4.13 Managing Trace Files The file management of the system is divided into file storage, file opening, file deletion and file formation.  File storage: for details, refer to 4.6.2 Trace naming  File opening: for details, refer to the operations in 4.11.1 Opening Trace Files  File deletion: the system support to delete several trace files at one time 【Operation】 File deletion  Press 【Menu】 key, and open the menu  Press 【 】 and 【 】 keys to move to “File” menu bar 58



 

Press 【 】 and 【 4.11.1 File Deletion:

】 keys to select “delete”, and press 【

Figure 4.11.1 File Deletion Press 【 】 and 【 】 keys to move the cursor, press 【 to delete. An “*” will appear at the back of the selected file. If you want to delete multiple files at the same time, press 【

】 key to enter. As shown in Figure

】 key to select the file that you want 】 and 【

】 keys to move the cursor 59

and select other files that you want to delete.  If you want to delete all files, press 【 】, 【 】, 【 】 or 【 】 keys to move the cursor and select 【SelAll】button and press 【 】.  You can deselect a file by selecting it again, or select 【Desel】 button and press 【 】 key to deselect all files. 】 key to finish  After finishing the selection of files, move the cursor to 【delete】, and press 【 the deletion  Format: this function can delete all files stored in the system at one time In 【Menu】“File”, select “format”, and press 【 】 key to finish the operation at one time.

Note: It should be cautious to perform the operation of “format”, and once formatted, the instrument data cannot be recovered.

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5 Equipment Maintenance 5.1 Equipment Routine Maintenance It shall make sure the long-term correct execution of the operation:  Before using, clean the connector of optical fiber all the time.  Prevent the equipment from dust.  Please use cotton cloth slightly dipped with water to clean the casing and the front panel.  Put the equipment in clean and dry place under room temperature.  Prevent the sunshine shooting directly at the equipment.  Prevent over high humidity or prominent temperature changes.  Avoid unnecessary striking and vibration.  In case of any liquid splashing on the surface of the equipment or permeating into the internal, please immediately shut off the power supply and wait for the equipment to dry completely. Warning It is prohibited operating with the machine on when the optical fiber connector is being cleaned; and the eyes are prevented from directly aiming at the interface.

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5.2 Charging the Battery In normal conditions, the nickel-metal hydride battery can be in service continuously for about 10 hours.  The charging status is displayed on the top of the main menu.  The equipment can also indicate the charging status though the LED on the front panel. Notes      



When the battery leaves the factory, all parameters have been set. If the instrument is left unused for long time, it is better to charge the battery once every three months The charging time for the battery depends on various factors, such as the type of battery and the ambient temperature and so on. Never put the battery under the environment with temperature exceeding 60 °C (140 °F). It can only use the appointed charger to charge the battery. According to the different purpose of the equipment, after a period of time, the charging status icon may not comply with the actual battery power (such as, the icon shows the power is sufficient, but the equipment is shut down due to insufficient power). Therefore, it must carry out a complete calibration circle. Use AC adaptor/charger to connect the equipment to the socket of power supply. The charging process will automatically start and stop. 62

Warning: Do not throw the battery into fire or water, and do not make the electrodes of the battery short circuit. Dismounting is forbidden.

Calibration of Battery Power After the battery is used for a period of time, due to reasons of battery aging, the power indication may have bigger error, and it can recover to normal by the following operation:  The battery is completely discharged Do not use adapter, start the machine, and the menu will close the automatic shutoff function until the battery power is used off, the instrument will automatically shut down.  The battery is completely charged Plug in the power supply adapter, start the machine and the menu will close the automatic shutoff function, until the charging indicator on the front panel of the instrument goes out, shut off the machine and restart. Note: For the charging of battery, the user can start the machine by pressing On/Off key. The failure of normal starting the system (the LCD light one time and shut off immediately) may be caused by too low battery power, and plug in the adapter for a period of time and it will recover to normal. 63

5.3 Recalibrating Equipments For OTDR equipment, the company suggests to return to the factory for calibration once a year.

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6 Fault Diagnosis 6.1 Frequently Asked Questions Problems The equipment cannot be charged

Reasons The battery power is used up

Resolutions 

Charge the battery



Replace to battery fully charged



Connect the equipment to the external power supply through AC adapter/charger

The equipment screen becomes black

The equipment is not connected to the

Connect the equipment to the external power

external power supply

supply through AC adapter/charger.

The external power supply has been pull

Make sure the two terminals of the external power

up

supply have been plug in

The battery power is used up and the



Charge the battery

equipment has been shut down



Replace to battery fully charged



Connect the equipment to the external power supply through AC adapter/charger

Characteristics on the screen is vague

The setting of illumination is not right

Adjust the illumination

The operating time of equipment is shortened

The battery may be used up

Replace the battery

The battery is not fully charged

Charge the battery 65

Application

program

displays

an

The tested optical fiber is too long

information, indicating it has found the event “optical

fiber

terminals

not

to

be

Make sure the length of the tested optical fiber is less than the maximum length that OTDR can measure.

distinguished”

6.2 Please Contact Technical Support Please contact the product agent or send email to the company for help

6.3 Transportation When transporting the equipment, the temperature shall be maintained within the specified range. Improper operation may damage the equipment during the transportation. It is suggested to abide by the following steps to reduce the possibility of equipment damage to the minimum:  Use the original package material to package the equipment during the transportation.  Prevent humidity being too high or temperature variations being too big.  Prevent the sunshine shoot directly at the equipment.  Prevent unnecessary striking and vibration.

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7 Guarantee 7.1 General Information The company guarantees to perform the warranty for defects caused by materials or process within one year since the initial delivery date of the equipment. The company simultaneously guarantees the equipment complies with the applicable specifications under normal application conditions. During the warranty period, the company will have right to determine to repair, replace or issue the credit card for any products having problems. The warranty also applicable to verify and adjust free to the products need repair, or perform verification and adjustment again to the products whose original calibration has something wrong. If the equipment is sent back for scale calibration within the warranty period, and is found it complies with all the issued specifications, the company will charge standard calibration fees. Note In case of the following cases, the warranty will be invalid     

The equipment is damaged due to the repair or treatment by the unauthorized personnel or technician not from the company. The warranty label is tore off. The chassis screws are not specified by the manual is moved away. The chassis is opened not according to the instructions of the manual. The equipment number has ever been modified, wiped off or moved. 67

 The equipment has ever been damaged due to improper use, negligence or accident. The warranty declaration will replace all the other definite statement, connotative or legal warranty declaration, which includes but not be limited to the suggestive warranty declaration for the commodity sales and commodity adaptability established for special purposes. In any cases, the company will not undertake the responsibilities for special fault s, accidents or various damages thus caused.

7.2 Responsibilities The company will not undertake the responsibilities for damage caused by using the products, and will also not undertake the responsibilities for any performance failure caused by other equipment the product is connected to or any system operation in which the product may be a part. The company will not undertake the responsibilities for the damage of the equipment, accessories and the software caused by improper use or modification without being authorized.

7.3 Exceptions The company reserves the right to change the design and the installation structures of various products at any time and undertakes no obligations to modify for the purchased products required by the users. Various accessories, including but not limited to the fuse, indicator light, battery and universal interface (EUI) etc. are not within the warranty scope. In case of the following cases, the warranty will become invalid: improper use or installation, normal wear and 68

fracture, contingency, illegal operation, negligence, fire, flooding, lightning or other natural accidents, reasons beyond the products or other reasons beyond the control of the company.

Important promote The replacement of optical connector that is damaged due to improper use or harmful cleaning will be charged for fees.

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