6
Baker Instrument Company
The Measure of Quality
O
PEN GROUND FAULT INDICATOR LAMP LIT
1.
Check that the tester is being operated with a two wire cord with a ground prong.
2.
Check for a broken ground connection in the power cord.
3.
Check that if being powered from an isolation transformer that a proper ground is
supplied to the tester.
4.
Check the mating ground pin receptacle at the power outlet for a bad connection.
5.
Check continuity from the ground prong on the input power receptacle to the Power
board P2 pin 1 and also to chassis ground.
6.
Check MOV 1, MOV 2, MOV 3 for electrical damage. If damage is found also check
for burnt traces on both sides of this assembly. Replace Power board if traces are
damaged.
•
Also to prevent future damage to this assembly or possible further damage,
measure and correct line voltage fluctuations so that they remain consistently with
the following parameters.
Unit
Line Voltage Range
Lower Upper
D6000
100 Volts AC
120 Volts AC
D12000
100 Volts AC
120 Volts AC
DS206
220 Volts AC
250 Volts AC
DS212
220 Volts AC
250 Volts AC
7.
Check signal at Q1 collector on the Power board for a .4 volt ripple, if not replace Q1.
8.
Check U9 pin 3 on the I/O board for a 0 volts and U9 pin 4 for five (5) volts DC, if
not replace U9.
9.
Check Q6 on the I/O board for a collector to emitter short, if so then replace Q6.
10.
Check for a shorted Open Ground LED.
