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Troubleshooting Load Stand
®
II
Problem
Description
Solution
Small Amplitude Changes
or Erratic Fluctuations in
Display Readings
Fluctuations in readings can be caused
by short to ground.
Using a Digital Multimeter (DMM) or ohmmeter,
check for shorts to ground as follows:
1. Set meter resistance scale to accommodate
maximum measured range.
2. Disconnect junction box wires of suspect
vessel from signal processor.
3. With one lead to earth ground and other
lead to white wire, check resistance on
disconnected wires:
If reading is less than infinite (i.e., there is
resistance), a short is indicated; proceed to
Step 4 to identify location.
If no short is indicated, investigate other
explanations for problem.
4. Starting with junction box closest to signal
processor in daisy chain, disconnect wires
connecting junction box to other junction
boxes. With one lead to earth ground and
other lead to white terminal on TB3, check
resistance on wires leading from junction
box:
If the reading is less than infinite (i.e., there
is resistance), short is indicated; proceed
to Step 5 to identify location. If no short is
indicated, proceed to next junction box in
daisy chain, disconnecting wires connect-
ing it to other junction boxes and checking
resistance. Perform for each junction box
down chain until short is located; proceed
to Step 5 to identify location.
Note:
Sun shield or junction box mounting
bolts are good locations for connecting
probe to ground.
5. Disconnect wires for one sensor from
above-identified junction box. With one
lead to earth ground and other lead to white
wire, check resistance on disconnected
sensor wires: If reading is less than infinite
(i.e., there is resistance), short is indicated.
Replace shorted sensor. If no short is indi-
cated, disconnect next sensor’s wires from
junction box and check resistances. Repeat
for each sensor wired to junction box until
short is located. Replace shorted sensor.
Summary of Contents for Load Stand II
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