ESAB Caddy Tig 1500i TA34, Руководство по обслуживанию

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SERVICE INSTRUCTIONS
0740 800 186 - 43 - © ESAB AB 2016
5. PM1, diode D3: measure between the positive of capacitor 15C1 and terminal T2. The
forward voltage drop must be 0.3 to 0.5 V.
6. PM1, diode D1: measure between the positive of capacitor 15C1 and terminal L2. The
forward voltage drop must be 0.3 to 0.5 V.
7. PM1, transistor Q2: measure the resistance between source, the positive of capacitor
15C1, and gate, pin 19 of the module. The resistance must be higher than 500 kohm.
8. PM1, transistor Q3: measure the resistance between source, terminal T2, and gate, pin
14 of the module. The resistance must be higher than 500 kohm.
Circuit diagram and measuring points for the semiconductor module
Checking rectifier and freewheel diodes
1. Disconnect the power source from the mains.
2. Dismantle the housing of the power source.
3. Use a Torx key no. T25 to unscrew and remove five screws from circuit board 15AP2.
The screws are marked on the picture below,
4. Bend out the circuit board so that it has no contact with the connections of the diode
module.
5. Use a multimeter in diode test position to measure the forward voltage drop of the two
diodes: see the picture below. The voltage drop must be 0.3 to 0.5 V.
6. If the diode module has to be replaced, follow the instructions on page 44.