Rice Lake Signal Conditioning Transmitter/Indicators - Manual (Page 6)

2 SCT Weight Transmitter Operator’s Manual
1.2 Equipment Recommendations
Failure to follow the installation recommendations will be considered a misuse of the equipment.
To Avoid Equipment Damage
• Keep away from heat sources and direct sunlight.
• Protect the instrument from rain.
• Do not wash, dip in water or spill liquid on the instrument.
• Do not use solvents to clean the instrument.
• Do not install in areas subject to explosion hazard.
1.2.1 Correct Installation Of Weighing Instruments
• The terminals indicated on the instrument’s wiring diagram to be connected to earth must have the same
potential as the scale structure (ground). If you are unable to ensure this condition, connect a ground wire
between the instrument and the scale structure.
• The load cell cable must be run separately to the instrument input and not share a conduit with other cables. A
shielded connection must be continuous without a splice.
• Use “RC” filters (quench-arcs) on the instrument-driven solenoid valve and remote control switch coils.
• Avoid electrical noise in the instrument panel; if inevitable, use special filters or sheet metal partitions to
isolate.
• The panel installer must provide electrical protection for the instruments (fuses, door lock switch, etc.).
• It is advisable to leave equipment always switched on to prevent the formation of condensation.
• Maximum Cable Lengths:
- RS-485: 1000 meters with AWG24, shielded and twisted cables
- RS-232: 15 meters for baud rates up to 19200
1.2.2 Correct Installation Of The Load Cells
Installing Load Cells:
The load cells must be placed on rigid, stable structures within 0.5% of plumb and level. It is important to use
mounting modules for load cells to compensate for misalignment of the support surfaces.
Protection Of The Load Cell Cable:
Use water-proof sheaths and joints in order to protect the cables of the load cells.
Mechanical Restraints (pipes, etc.):
When pipes are present, we recommend the use of hoses, flexible couplings and rubber skirted joints. In case of
rigid conduit and pipes, place the pipe support or anchor bracket as far as possible from the weighed structure (at a
distance at least 40 times the diameter of the pipe).
Connecting Several Load Cells In Parallel:
Connect several load cells in parallel by using, if necessary, a watertight junction box with terminal box. The load
cell connection extension cables must be shielded, run individually into their piping or conduit and laid as far as
possible from the high voltage cables.
Welding:
Avoid welding with the load cells already installed. If this cannot be avoided, place the welder ground clamp close
to the required welding point to prevent sending current through the load cell body.
Important