Temperature Probe Test (Vc4Gd/6Gd) - Vulcan-Hart VC4G Service Manual

VC4G & VC6G SERIES FULL SIZE CONVECTION OVENS - SERVICE PROCEDURES AND ADJUSTMENTS
NOTE: If oven is equipped with "Cook and Hold"
option, set to Cook (normal cooking) before
continuing.
3. Set the temperature control to the maximum
setting.
4. Check machine data plate for correct voltage to
oven. Refer to diagram below for proper terminal
locations and voltages before checking the
control. Use the correct terminals for the
corresponding voltage.
5. Turn the power switch to ON.
Fig. 54
6. Check for proper voltage across terminals COM
AC to 120VAC or COM AC to 208-240VAC for
power to the control.
A. If correct, proceed to step 7.
B. If incorrect, problem is not with the
temperature control. See
TROUBLESHOOTING.
7. Check relay voltages on the board:
A. For 120VAC controls - check across
OUTPUT RELAY terminal (left side) to
120VAC terminal for input to the internal
relay. Check across OUTPUT RELAY
terminal (right side) to 120 VAC for output
from the internal relay.
B. For 208-240VAC controls - check across
OUTPUT RELAY terminal (left side) to
208-240VAC terminal for input to the
internal relay. Check across OUTPUT
RELAY terminal (right side) to 208-240VAC
for output from the internal relay.
1)
2)
8. Set the temperature control to the minimum
setting.
NOTE: Oven temperature must be above 300°F.
9. Check for zero (0) volts AC across terminals
OUTPUT RELAY terminal (right side) to 120VAC
or OUTPUT RELAY terminal (right side) to
208-240VAC for no output from the internal relay.
A. If correct, temperature control is functioning
properly.
B. If incorrect, check temperature probe as
outlined under TEMPERATURE PROBE
TEST (VC4GD/6GD).
1)
TEMPERATURE PROBE TEST
NOTE: The temperature probe used in conjunction
with the Solid State Temperature control is an RTD
(resistance temperature detector) of the Thermistor
Page 27 of 75
If input voltage to the internal relay is
correct, proceed to step 8. If input
voltage to the internal relay is not
present, problem is not with the
temperature control. See
TROUBLESHOOTING.
If output voltage from the internal relay
is correct proceed to step 8. If output
voltage from the internal relay is not
correct, check temperature probe as
outlined under TEMPERATURE
PROBE TEST (VC4GD/6GD).
If temperature probe is OK:
a. Turn the power switch OFF.
Disconnect the
electrical power to the machine and
follow lockout / tagout procedures.
b. Replace the temperature control
and check calibration as outlined
under SOLID STATE
TEMPERATURE CONTROL
CALIBRATION (VC4GD/6GD).
(VC4GD/6GD)
Disconnect the
electrical power to the machine and
follow lockout / tagout procedures.
F24682 Rev. D (1016)