Operating the at30 – Exide Technologies Section 94.40 User Manual

Page 38

OPERATING THE AT30

Adjusting Ground Detection Sensitivity

You can adjust the sensitivity of
the ground detection alarm circuit.
You must have a test resistor
whose value is the sensitivity you
want. You can adjust the
sensitivity from 5 to 50 k

Ω

The potentiometer for adjusting
ground detection circuit
sensitivity is located on the main
control circuit board. It is the
lower of the two potentiometers
labeled

RA3 SENS, as shown in

the figure at the right.

NOTE: Do not try to adjust the upper potentiometer labeled RA2

BALANCE. This adjustment is made at the factory for proper
circuit operation.
CAUTION: Before connecting or disconnecting a test resistor,
de-energize and lock out all ac and dc voltage sources to the
AT30. Check with a voltmeter before proceeding. Restart the
AT30 only when necessary to make the sensitivity adjustment. If
your battery is grounded, do not attempt this procedure.

Remove the safety cover. Connect the test resistor between

TB1(+) and

the ground terminal. Refer to the standard internal component layout
drawings starting on Page 72 in Appendix C For I/O panel layout and all
terminal wire specifications.

Adjust

RA3 counterclockwise until the

front panel indicator goes out, and adjust
slowly clockwise until the

POS GND

indicator just lights.

Make this adjustment slowly, for the
indicator is updated once every four
seconds. De-energize and lock out power
to the AT30. Remove the test resistor
and verify that the indicator goes out.

Connect the test resistor between

TB1(-)

and chassis ground Verify that the

NEG

GND indicator lights. If not, adjust RA3
clockwise until it does. Remove the test
resistor.