Rice Lake Intercomp CS 1500 - Users Manual - Manual (Page 23)

CS1500, Users
Rev S, June, 2009
23
Troubleshooting
Caution
Changing some parts on the circuit board may cause a large change in
calibration while others may or may not change the calibration,
depending on the nature of the problem.
The reference designators for the IC chips are on the “A/D 20-BIT” board unless
indicated otherwise.
Problem: no power, nothing on display
Fix:
If nothing can be seen on the display, there probably is no power reaching the
scale circuitry. Possible causes: bad or shorted battery pack, bad switch circuit,
bad voltage regulator, or bad keypad. Power might be reaching the unit, but the
power supply might be shorted by a component or PCB trace in the power
supply circuitry.
Problem: random display (display usually reads “8.8. 8.”)
Fix:
Check crystal (Y1). If the micro-controller is not receiving the correct or any
oscillation, the microprocessor is not able to function properly. Other possibilities
could be bad microprocessor (U1) or display driver (U1 & U2 on “GPI DISPLAY”
board) circuitry not functioning.
Problem: low battery indicator won’t turn off (display blinks “LB LB LB LB”)
Fix:
The display will be blinking “LB
LB LB LB”. Check to make sure battery power is too low.
Look at the cells and charger circuit for these problems. If that is not the cause,
the display driver ( U1 & U2 on the GPI display board) or low voltage circuitry
could be bad.
Problem: rechargeable battery life has decreased
Fix:
The rechargeable batteries provided by Intercomp are high quality, high capacity
Ni-Cad. However, all Ni-Cad batteries can exhibit some “memory” effects if they
are repeatedly discharged to a certain point before recharging. If your observed
battery life has decreased significantly from its initial performance, you may want
to try this battery-conditioning sequence: Fully discharge the batteries by
running the CS1500 until the display blinks “LB” (low battery) and keep the unit
powered until the batteries are fully discharged. Following this, recharge the
battery completely (typical charge time is 16 hours). This discharge/recharge
cycle may need to be repeated. If this does not help, you may need to replace
the Ni-Cad batteries.