11
Service Manual for Dry Channel HDC3/HDC6 Units
COMPONENT TESTING
Most component testing can be performed using
a Digital Multimeter.
NOTE:
When a continuity test is being performed,
the HDC3/HDC6 must be isolated from the
power source to prevent damage to the test
equipment.
Primary Power Check
CAUTION: Input voltage source must
match voltage indicated on
dataplate. Voltage should be 208
or 240 VAC depending upon the
application.
1. Check the input voltage source for correct
measurement of 208 or 240 VAC. If input
voltage is not present, check for open circuit
breakers or fuses supplying the input power.
2. Measure the voltage across the input terminals
on the Main Power On/Off Switch. Voltage
should be the same as input voltage source.
If voltage is not present, check power source
and power cord.
3. Set the Main Power On/Off Switch to on and
check for source voltage across the switch
output terminals. If voltage is not present
replace switch.
4. Measure voltage across primary of 24 Volt Step-
Down Transformer. If voltage is not present,
check wiring. If input voltage is present, the
primary power check is complete.
TESTING AND TROUBLESHOOTING
Fault Conditions
Fault conditions are indicated on the Control
Display.
1. High Temperature Fault
– For a High
Temperature Fault the display will show “HIX”,
where X indicates the channel (“F” for front,
“C” for center, and “b” for back). A buzzer will
sound for one second every 30 seconds. The
operator can cancel this alarm by pressing any
button on the Control Panel. The alarm will
reactivate after 20 minutes if the problem has
not been rectified. Both relays for the channel
will be turned off while the fault exists.
2. Low Temperature Fault
– For a Low
Temperature Fault the display will show
“LOX”, where X indicates the channel
(“F” for front, “C” for center, and “B” for back).
A buzzer will sound for one second every 30
seconds. The operator can cancel this alarm
by pressing any button on the Control Panel.
The alarm will reactivate after 20 minutes if
the problem has not been rectified.
3. Probe Open/Shor
t – For a Probe Open/ Short
Fault the display will show “PRX”, where X
indicates the channel (“F” for front, “C” for
center and “B” for back). The operator can
cancel this alarm by pressing any button on
the Control Panel. The alarm will reactivate
after 20 minutes if the problem has not been
rectified. The relays for both zones of the
channel with a probe fault will be turned off
while the fault exists. The control will display
000°F for the temperature of the channel with
the fault condition.
