1 8
Problem
Description
Solution
Small Amplitude Changes
or Erratic Fluctuations in
Display Readings
Fluctuations can be caused by small
amplitude drift or oscillation, with
peak-to-peak disturbance of 0.1 % to
0.5 % of full scale, is normal.
Problem likely to be noticed shortly
after initial installation.
Reduce drift or oscillation by setting 'count by'
and 'averaging' appropriately on signal proces-
sor (refer to signal processor manual).
Fluctuations can be caused by mois-
ture in the cable conduit, junction
boxes, or PCBs.
Problem likely to be noticed on system
that previously functioned correctly.
Check conduit, junction boxes and PCBs for wa-
ter contamination. Find water entry source and
correct problem. Dry with a hair drier. Remove/
replace corroded parts and materials.
Caution: If using sealant to eliminate water
entry, use Sikaflex
TM
1A polyurethane sealant,
Sikaflex™ ProSelect Construction sealant or
Dow Corning
TM
RTV 739 or RTV 738. Other seal-
ants may contain acetic acid, which is harmful to
sensors and electronics.
Fluctuations can be caused by jammed
bolts or heat radiation/ conduction.
Problem likely to be noticed shortly
after initial installation or on system
that previously functioned correctly in
cool or overcast weather.
Loosen nuts on top bolts and inspect top bolts.
· Top bolts free to move in holes: If vessel is
heated, it may be radiating or conducting heat
through vessel legs and affecting Load Stand
®
sensors.
· To reduce head radiation/conduction:
a) Insulate vessel.
b) Contact Anderson-Negele to discuss adding
a high temperature insulating pad.
· Top bolts jammed: Jammed top bolts indicate
undersized bolt holes on vessel mounting
flange and/or vessel support movement
beyond limits of Load Stand
®
clearance
holes. Resulting side loads affect Load Stand
®
sensors.
· To reduce side loads:
a)
Enlarge vessel mounting flange bolt holes
to provide additional clearance.
Fluctuations can be caused by dam-
aged Load Stand
®
sensor.
Problem likely to be noticed shortly
after initial installation or on system
that previously functioned correctly.
Using Digital Multimeter (DMM), check resis-
tance for individual Load Stands:
1. Set meter resistance scale to accommodate
measured range up to 20,000 Ω.
2. At the suspect Load Stand
®
junction box,
remove wiring at TB1 and TB2, which
connects to other Load Stands and signal
processors.
Troubleshooting Load Stand
®
II
Troubleshooting Load Stand
®
II
Summary of Contents for Load Stand II
Page 23: ...23 Notes ...
Page 24: ...2 4 Notes ...
