Kistler-Morse KM L-Cell Bolt-On User Manual
Page 14
2: Prepare for Installation
2-5
Testing Sensors with K-M Test Meter
The KM Test Meter (Figure 2-1) is designed specifically to test KM
sensors. If you do not own a Test Meter, disregard this section and
proceed to Testing Sensors with Digital Multimeter.
Note:
The Test Meter display indicates Low Battery or behaves
erratically when the batteries are weak. When this occurs, replace
the batteries before testing.
1.
Connect the red, white, and black wires of a sensor to the
corresponding Test Meter terminals, as shown in Figure 2-1. Place
the sensor on a stable surface.
2.
Turn on the power to the Test Meter and set the Simulate/Test
switch to the Test position. Verify the sensor’s no-load output
is 0 ± 100 mV.
3.
Repeat Steps 1 and 2 for each sensor.
If the reading for any sensor is outside the specifications described
above:
A. Proceed to Testing Sensors with Digital Multimeter below to
determine the resistance values for the sensor, and
B. Contact KM for assistance after determining the resistance values
and before proceeding with the installation.
Testing Sensors with Digital Multimeter (DMM)
Follow this procedure to test the sensors if you do not have a KM Test
Meter or if the no-load output using the Test Meter was out of range for a
sensor:
1.
Set the ohmmeter resistance scale to accommodate a measured range
up to 20,000 ohms.
2.
Put one DMM lead on the sensor’s white wire and the other lead on
the red wire. Place the sensor on a stable surface. Verify the red-to-
white resistance is 4000 ± 200 ohms for an L-Cell, 8300-8700 ohms for
a 3 inch Microcell (also non-standard), or 1800-2200 ohms for a 2 inch
Microcell.
3.
Put one DMM lead on the sensor’s white wire and the other lead on
the black wire. Place the sensor on a stable surface. Verify the black-
to-white resistance is 4000 ± 200 ohms and within 30 ohms of the red-
to-white reading from Step 2 for an L-Cell, 8300-8700 ohms and within
20 ohms of Step 2 for a 3 inch Microcell (also non-standard), or 1800-
2200 ohms and within 20 ohms of Step 2 for a 2 inch Microcell.
Repeat this procedure for each sensor. If the reading for any sensor is
outside the above ranges, contact KM for assistance before proceeding
with installation.
+EX
SIG
-EX
red
white
black
Fig 2-1. KM Test Meter
Replace L-Cell or Microcell in its packing material until
ready to install.
Note: