Heating Elements (Electric Model) - Vulcan-Hart VGCTS16 Service Manual

ROUND TILTING BRAISING PANS - SERVICE PROCEDURES AND ADJUSTMENTS
Potentiometer
Perform the following test procedure to verify the
potentiometer is functioning properly and to confirm
the temperature setting of the dial. A V-O-M
connected from TC (-) to the wiper (red) on the
potentiometer will read a voltage that corresponds to
the set point temperature. Ex. If the set point is
300°F the DC voltage measured at the wiper should
be approximately 1.49 volts.
1. If the thermocouple condition has not been
verified as described in step 3A above, place a
jumper across TC (-) and TC (+). If the
thermocouple condition has been verified,
proceed to step 2.
NOTE: Remove jumper when test is
completed.
2. Connect the black meter lead of a V-O-M to the
TC (-) on the temperature controller.
3. Connect the red meter lead of a V-O-M to the
red wire (wiper arm) on the potentiometer.
4. Turn the power switch on and set the
temperature dial to 100°F. Increase set point to
200°F, 300°F, 400°F and 450 °F while
monitoring the voltage change between dial set
points. Compare the meter readings to the
chart below.
TEMPERATURE
SETTING (°F)
100
200
300
400
450
A. If the voltage measurements agree with
those listed in the table and the increase in
voltage was smooth without drops or
spikes then the potentiometer is
functioning properly.
B. If the voltage measurements do not agree
with those listed in the table or the
increase in voltage was not smooth but
with drops or spikes then the
potentiometer is not functioning properly.
Replace the temperature controller and
potentiometer assembly and check unit for
proper operation.
APPROXIMATE
DC VOLTAGE
0.38
0.93
1.49
2.0
2.3
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HEATING ELEMENTS
(ELECTRIC MODEL)
WARNING: THE FOLLOWING STEPS REQUIRE
POWER TO BE APPLIED TO THE UNIT DURING
THE TEST. USE EXTREME CAUTION AT ALL
TIMES.
1. Measure the voltage at the heating element
terminals and verify it against the data plate
voltage.
A. If voltage is incorrect, find the source of
the problem.
2. If voltage is correct, check current draw (amps)
through the heating element lead wires. If
current draw is correct then heating element is
ok. See table below for proper values.
A. If current draw is not correct then, replace
heating element.
3. Check for proper operation.
AMPERAGE
TOTAL
VOLTAGE
KW
1 PH
208 7.5 36.1
240 7.5 31.3
480 7.5
NOTE: Values in the table are nominal. Tolerance is
+5/-10 %.
OHMS PER
PER LINE
ELEMENT
3 PH
20.9 17.4
18.1 23.1
9.0 30.6