B&K 1794 instruction manual Unregulated O/P Voltage

( B ) UNREGULATED O/P VOLTAGE

UNREGULATED O/P VOLTAGE

Is IC LM324 OK ?	N
Y
Is Voltage Pot Open OR	N
Pot Wire is Reaching PCB ?
Y
Are Mosfets OK ?	N
Y
Is Gate Wire of Mosfet	N
Reaching PCB ?
Y
Are Diodes D3 and D4 on	N
Front Panel PCB OK ?
Y

Is INT & COM Terminal on Back Panel Short ?

N

Short INT COM Terminal when External Programming

is not in use.

Replace the IC.

Replace the Voltage Pot and Ensure proper continuity with the PCB

Replace the Damaged

Mosfet.

Ensure proper continuity of Gate Wire and PCB.

Replace the Damaged

Diode.

1.Check IC LM324 on Front Panel PCB (L1791-FP-CNT0603). It might be damaged.

2.Check Voltage Potentiometer (5K Pot), whether it is open or whether the wires associated with Voltage Potentiometer is reaching the Front Panel PCB.

3.Check the Mosfets and Zener Diodes across Mosfet. It might be Short.

4.Check Diodes D3 and D4 on Front Panel PCB. It might be Leaky or Short.

5.Ensure proper continuity of Gate Wire on Front Panel PCB and Mosfet module.

6.Ensure INT and COM Terminal at Back Panel are short when External Programming is not in use.

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