Qb1 Quick Break Tester - Operating Manual - Jun18.pdf

Operating Manual

Faraday Road, South Dorcan Industrial Estate, Swindon, SN3 5HE, UK Telephone: + 44 (0)1793 524566 Fax: +44 (0)1793 490459 Email: [email protected] Web: eu.magnaflux.com Bahnhofstr 94-98, 73457 Essingen, Deutschland Telephone: +49 (0) 7365 81-0 Fax: +49 (0) 7365 81-449 Email: [email protected] Web: eu.magnaflux.com/de

QB1 Quick Break Tester Part number 148335

1. AN EXPLANATION OF QUICK BREAK

5. TROUBLESHOOTING

When current passes through a coil, it creates a magnetic field. If the current is stopped, the magnetic field collapses and induces a current in the opposite direction in the coil. This, in turn, creates a magnetic field in the opposite direction. The cycle continues back and forth until the current is dissipated through resistance. This effect is commonly called ring down.

PROBLEM: INDICATOR LIGHT DOES NOT ILLUMINATE.

Quick Break is a term associated with the circuitry employed to rapidly terminate high amperage direct current (DC) flowing through a magnetizing coil. The resulting rapid collapse of the coils magnetic field imparts a desirable residual field within the part under test. The nature of this field is advantageous for disclosing certain transverse discontinuities on the surface of the part, even when the continuous method is being employed. When the ring down dissipation is too slow, the resulting effect could give inconsistent results. At the very least, it will cause undesirable leakage fields on the outer edges of the part under test. Quick Break can give you sharper resolution of transverse indications. The ring down rate, frequency, and peaks are all functions of the coils size, voltage and resistance. It is much like ringing a bell. Different sized bells will give you different tones (Frequency & Coil Size). Different hammer hits will change how long the bell resonates (Voltage Drop). Putting your hand on the bell will also change how long it will resonate (Resistance). With Quick Break, the concern is the dissipation of the energy. If the energy is dissipated too slowly the resulting residual field is not properly developed. The frequency is tied to the coil size, which is not usually something that can be manipulated. Resistance can be manipulated in the design of the unit. The voltage drop is determined by the machine design and the amperage desired.

Possible cause

Solution

Amperage set too low to activate.

Equipment must be set to produce over 15,000 amp turns, 3,000 amps through a 5 turn coil or 2,000 amps when connected in series with a 5 turn coil wrap.

Damaged or defective bulb.

Contact Authorised Magnaflux Service Centre to repair or replace (QB1 Replacement Bulb part number: 106793).

Damaged coil due to misuse.

Contact Authorised Magnaflux Service Centre to repair or replace.

6. CLEANING Use only mild soap and damp cloth to clean the tool. Never let any liquid get inside the housing. Never immerse any part of the tool into a liquid. Store protected in a clean, dry environment.

7. CUSTOMER SUPPORT The QB1 is a certified tester. If you have a question about the purchase, operation, re-certification or servicing of the QB1, please contact Magnaflux (details overleaf. You may also contact your local distributor or Magnaflux Authorised Service Centre directly; contact information can be found on our website: eu.magnaflux.com

By designing the QB1 tuned for a certain amperage, we can determine if the Quick Break of the unit is functioning properly. The testers are designed to verify the voltage induced by the coil. The voltage induced is a function of the inductance of the coil and the rate of change of the current. Although it is a function of time, Quick Break is like velocity and it is a product of the inductance multiplied by the rate of fall (amps per second). The QB1 gives us an easy functioning gauge that allows us to verify the units operation.

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2. PRECAUTIONS

Indicating Lamp

• The QB1 is designed for 3 Phase, Full Wave and DC output machines only. Do NOT use with 1 Phase DC, Half wave or AC output machines. • The tester should always be used as shown for the appropriate component.

Copper Bus

• Occasionally, the bulb might flash at the beginning of the magnetic cycle. This indication should be ignored, as it is the break (current turning off) that is being tested. • Always avoid dropping the tester as internal circuits could be damaged. • The Quick Break Tester is tuned for 2000 amps no matter the coil size. All tests should be done as close as possible to 2000 amps.

Figure D-3: Quick Break Tester with Bus Bar and Brackets

Note: Often the Bus Bar and White Metal Cover will not be used with the Quick Break Tester. If necessary, these components can be removed.

3. OPERATION Cables to Coil or Induced Current Fixture Tester

3.1 CHECKING A COIL ON A WET HORIZONTAL UNIT 1. Center the Coil in a convenient spot for easy access to the bottom of the coil and the current (mag) activation button. 2. Remove all ferrous materials from inside the coil. 3. Place the Magnaflux QB1 on the bottom of the coil with the studs facing to the centre of the coil. Note: Never clamp the QB1 between the Head and Tail Stocks. This test will not confirm quick break and may damage tester. 4. Set mag current as close as possible to 2000 amps. 5. Set the mag shot time for 0.5 to 1 second.

Tailstock

Headstock Contact Block

Figure D-4: Testing Contact Circuit

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6. Initiate the mag current shot and observe the tester’s indicating lamp at the end of the mag cycle. Flash of the lamp indicates a good Quick Break; absence of flash is indicative of “Quick Break” malfunction or the unit does not have the Quick Break feature. 7. Repeat this test firing at least 20 mag shots. The bulb should flash a minimum of 16 times (80%). Be aware of the unit’s duty cycle when performing this test. Exceeding the duty cycle can affect the quick break function as well as the unit. Note: At times the lamp may flash at the beginning of the mag cycle. This should be ignored as the end (break) of the cycle is the concern.

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3.2 CHECKING A REMOTE COIL OR CABLE WRAP WITH EXTERNAL POWER SOURCE

4. IDENTIFYING PARTS

1. Install the bus bar and cover on the Quick Break Tester. 2. Place the coil/cable wrap in a convenient spot for easy access to the bottom of the coil and the current (mag) activation button. Cable wraps should be five (5) turns to match the tuning of the quick break tester. 3. Remove all ferrous materials from the coil or cable wrap. 4. Place the Magnaflux QB1 in series with the cable going to the coil. Note: Never clamp the QB1 between Head and Tail Stocks. This test will not confirm quick b reak and may damage tester. 5. Set mag current as close as possible to 2000 amps. 6. Set the mag shot time for 0.5 to 1 second. 7. Initiate the mag current shot and observe the tester’s indicating lamp at the end of the mag cycle. Flash of the lamp indicates a good Quick Break; absence of flash is indicative of “Quick Break” malfunction or the unit does not have the Quick Break feature. 8. Repeat this test firing at least 20 mag shots. The bulb should flash a minimum of 16 times (80%). Note: At times the lamp may flash at the beginning of the mag cycle. This should be ignored as the end (break) of the cycle is the concern.

Figure D-1: Quick Break Tester without Bus Bar and Brackets Coil

Tester

Figure D-2: Testing Coil Circuit

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