Salter Brecknell CS-250 - Manual (Page 21)

CS-250 Series Chair Scales Service Manual
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
Check the strain gauge areas become compressed

Check any physical damage (body bent or twisted) to the load cell

Check load cell cable, all leads are connected, any cut, splits or tears.

Check load cell for proper input and output resistances
Electrical Test:
Use an accurate multimeter to check the ohms
Load Cell Connections
Signal + Green
Supply + Red
Signal - White
Supply - Black
Shield
Resistance
Measuring Points Resistance
Red (+ Exc) to Black ( –Exc) 409 ±6Ω
Green (+Sig) to White ( –Sig) 350Ω ±3Ω
Leakage Resistance

Check each of the load cell wires to the load cell cable screen.

Check each of the load cell wires to the load cell body.
These readings should be greater than 1000mΩ or OL.
If this reading is less than 1000
mΩ, then this load cell has leakage between
the internal circuit and the load cell body or cable screen
Zero Balance

Connect the load cell to a stable DC source of between 5 to 10V

Connect multimeter to mV and connect to the load cell signal wires

The meter should read 0.00mV ± approximately 1 % of full load.
If the output reads greater than ±10% of full scale capacity, then the load cell
will require replacement.