T Scale TFB sereis, Service Manual

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TPF / TFB Series Floor Scale Service Manual
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Signal + Green
Supply + Red
Signal -
White
Supply -
Black
Shield
Resistance
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.
6.6. Check Indicator Voltages
If the problem is in the Indicator, use a multimeter to check the following voltages

AC Power

Adaptor Voltage

PCB Input Voltage

Check Battery Voltage and Charging Voltage
Follow the instructions in the Indicator manual for to check the voltages.
Measuring Points Resistance
+ Exc to
–Exc (Input) 350 ± 3.5 Ω
+Sig to
–Sig (Output) 351 ± 2 Ω