BST-GFL31 User Manual
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2.2 Operation Preparation
You are suggested to prepare well as below before going to the filed for earth fault tracing::
1) Make sure that both BST-GFL31 signal generator and receivers are fully powered. Signal generator
can work with power adaptor connecting with AC power supply.
2) Familiarize with onsite wiring for target DC system. It will be very important and helpful to have the
detailed wiring instruction indicating how each equipment is connected in the whole DC system.
3) For security purpose, please wear helmet, insulation-protected gloves and other protecting facilities
during operation.
4) Judge which busbar has faulty grounding:
A. DC circuit:
Use a multi-meter, switch to DC voltage measurement mode, and respectively measure the voltage
between busbar (negative and positive) and ground. Normally both absolute values should be equal
(around half of nominal voltage). If one of the voltage values is lower, this busbar should have faulty
grounding.
B. AC circuit:
Switch the multi-meter to AC voltage testing mode and respectively test the voltage value between
each power line (phase line and null line) and ground. Normally both absolute values should be the
same. If one of the voltage values is lower, that line should have earth fault.
5) Connect testing leads with signal generator and current detectors with signal receiver.
2.3 Wire connection with DC System
Fig 2.3.1
First connect the testing leads with signal generator, red lead with red socket and black lead with black
socket (Fig 2.3.1). Make sure that they are not mixed up. Then connect other ends of the leads with
alligator clips. After correct judgment on which busbar has ground fault, connect the testing leads with
the DC system as below:
1) If positive busbar has ground fault, connect red lead with positive busbar and black lead with ground.
Fig 2.3.2 Fault on positive busbar
Summary of Contents for BST-GFL31
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