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SNOW/ICE CONTROL INSTALLATION MANUAL | PART NO. 23918 REV B
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6. Now, press the GFEP Test/Reset button on the unit
face plate. The GFEP LED should ash, during which
time you should hearing some clicking sounds
from the relays inside the unit, and the amp meter
reading should again read 0 after the GFEP self-test
is complete. Record results on page 3 of this manual.
Remove the amp meter or voltmeter. Do not yet re-
install the unit front plastic cover or face plate.
7. Proceed to sensor testing below.
CIT–1 AND GIT–1 SENSOR TESTING
The CIT–1 and GIT–1 sensors have two interrelated
systems: the temperature sensing system and the moisture
detection system. Complete testing of the sensor involves
manipulation of both. The tools needed for this procedure
are a voltmeter and an aerosol circuit cooler (“Freeze
Spray” is preferred) or cup of ice water. The Freeze Spray
is available at most electric supply stores.
Ensure that the moisture sensing grid on the sensor is
clean and dry.
Follow the steps below to perform the CIT–1 and GIT–1
sensor post-installation test procedure. The SIT–6E testing
procedure is on the next page.
1. Connect the voltmeter across the black and red leads
from the sensor (low-voltage wiring terminals at the
control). Connect the black test lead to the black wire.
You should obtain a reading of 23 to 28 VDC. Now,
check the reading across the black and white sensor
leads. You should read 22 to 28 VDC with a warm
(above 38°F) and dry sensor. Both the SNOW LED and
HEAT LED should remain off.
2. Cool the temperature probe of the sensor with
the Freeze Spray. You should see frost form on the
temperature probe. Alternately, place the temperature
probe in ice water. The SNOW LED and HEAT LED
should remain off.
3. Using a moist nger, touch the moisture sensing grid
on top of the sensor. Both the SNOW LED and HEAT
LED should come on and the voltage between the white
and black sensor leads should be less than 2 VDC.
4. With the unit cold and the sensing grid moist, allow
the unit to warm up to above 38°F. The SNOW LED
should turn off and the HEAT LED should stay on and
the voltage should return to 22 to 28 VDC. Record
results on page 2 of this manual.
5. If testing a SIT–6E sensor, proceed to the next section
now. If testing is complete, with unit powered off,
restore all wiring connections and re- install the face
plate and clear plastic cover. Set the Hold-On Time
control dial to the desired setting.
SIT–6E SENSOR TESTING
If paving material or other residue adheres to the sensing
elements, clean the surface with a Scotch™ Brite Pad.
Avoid using metallic or coarse abrasives or detergents.
Regardless of weather conditions, the functional operation
of an installed SIT–6E sensor can be determined using a
digital voltmeter (DVM) and a 10-pound (4.54kg) bag of
crushed ice as described below.
1. With the DVM set to the 100 VDC range, verify the
sensor supply voltage by connecting the negative
(–) test lead to the sensor black wire and the positive
(+) test lead to the sensor red wire. A DVM reading
between 23 and 28 VDC is acceptable.
2. With the negative (–) test lead remaining in place,
reconnect the positive (+) test lead to the sensor white
wire and conrm there is 22 to 28 VDC present. Both
the HEAT LED and the SNOW LED should be off.
3. Place the entire contents of the bag of crushed
ice on top of the sensor and allow a time lapse in
excess of 20 minutes before observing that less
than 2 VDC is indicated by the DVM. Depending on
ambient conditions, however, this might take only a
few minutes, in which case, that is not a problem. (A
nominal temperature below 38°F or 3.3°C must be
detected before the sensor’s normally-open contact
is closed. If the sensor surface temperature was
excessive prior to beginning this procedure, it will be
necessary to extend the cool-down time interval by as
much as an additional 20 minutes.) Most importantly,
make sure both the HEAT LED and the SNOW LED
come on. Record results on page 2 of this manual.
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