6
077_D 2051
© 2020 tekmar Control Systems Ltd.
Installation – Indoor Sensor 077
Sensor Testing
Instructions
A good quality test meter
capable of measuring up to
5,000 kΩ (1 kΩ = 1000Ω) is
required to measure the sen-
sor resistance. In addition to
this, the actual temperature
must be measured with either
a good quality digital ther-
mometer, or if a thermometer
is not available, a second
sensor can be placed along-
side the one to be tested and
the readings compared.
First measure the tempera-
ture using the thermometer
and then measure the resis-
tance of the sensor at the
control. The wires from the
sensor must not be connect-
ed to the control while the
test is performed. Using the
chart on the following page,
estimate the temperature
measured by the sensor.
The sensor and thermometer
readings should be close. If
the test meter reads a very
high resistance, there may be
a broken wire, a poor wiring
connection or a defective
sensor. If the resistance is
very low, the wiring may be
shorted, there may be mois-
ture in the sensor or the sen-
sor may be defective. To test
for a defective sensor, mea-
sure the resistance directly at
the sensor location.
Do not apply voltage to a
sensor at any time as dam-
age to the sensor may result.