20
Ballast Tray Troubleshooting Procedure
Troubleshooting All Fluorescent Fixtures
Safety First:
Voltage and current measurements present
the possibility of exposure to hazardous voltages and
should be performed only by qualified personnel. Many
troubleshooting techniques require measurements with
input voltages applied requiring extra precautions to avoid
electrical shock. Use proper safety equipment such as eye
protection and gloves when performing electrical
measurements.
Inoperative Fixture:
Often, a fixture becomes inoperative dure to causes not
attributable to the ballast. It is therefore important to
examine all fixture components before removing the
ballast for replacement. We recommend the following
general procedure for both magnetic and electric ballasts:
1.) Replace or check all lamps to ensure satisfactory
operation.
2.) As lamps are removed, examine all sockets to ensure
they are not damaged or broken and are making proper
and positive contact with the lamps.
3.) examine all electrical connection within the fixture,
including at the lamp socket, to ensure conformance
with the wiring diagram (see Wiring Diagram).
To left is a systematic approach for troubleshooting most
problems than arise regarding fixture suing ballasts with
startup protection. For those situations when this
document does not assist in correcting the problem, the
manufacture should be contacted.
Note:
Programmed Start Ballasts include lamp end-of-life
circuitry. This circuit is included to maximize lamp life
when one lamp frails in the circuit. The feature enables
the ballast to detect when lamps fail and safely removes
prow for the lamp by going into a shutdown mode. The
ballast also goes into a shutdown mode when it detects
lamps not properly placed in the sockets. When
troubleshooting the circuit, make sure lamps are placed
properly in the sockets. Programmed Start ballasts also
include a re-strike feature that will restart the lamps after
the failed lamp has been replaced. Open circuit voltage
cannot be measured dure to lamp end-of-life circuitry.
Start here
Lamps Out?
Fixture Operational
No
Bring lamps
to full output
Yes
Proper supply
voltage to
ballast?
Yes
Power wires
secured at
ballast?
No
Correct
Voltage
Problem
No
Re-secure
hot &
neutral
wires
Yes
Ballast is
shutdown
Proper
wiring at
lamp
sockets?
No
Rewire or
replace 4
pin socket
harness as
needed
Yes
Loose wiring at
connector?
Yes
Re-insert
wire of
replace
connector
No
Unplug lamp and
reinsert after 3 seconds
Lamps
Start?
Switch existing lamp
with known good lamp
No
Lamps Start?
Replace
defective ballast
No
