Nova-Tech PGW Series User Manual

Page 40

Page 40 of 44

Poor Linearity

Usually a mechanical
problem

Electronic Problems

Re-check repeatability

*Inspection of the flexures for damage
or loose hardware may be required

*Use the Linearity Function in the
service menu to reset linearity

*A problem in the analogue circuit board
or power supplies can cause poor
linearity. Make sure all mechanical
problems have been eliminated first

OTHER PROBLEMS:

Cannot calibrate

Zero shifted more
than allowed

Calibration timeout

*Check all flexures for damage

*Reset factory calibration

*Verify linearity and repeatability

*The balance may be unstable. Verify
stability as above. Try using a more
aggressive filter

Calibration weight
motor does not stop

*Check the cables to the motor, try
plugging the balance into the power
again

*Look for friction in the calibration
weight movement

*Check the opto-coupler that controls
the motor position.

RS-232 not working

Doesn’t print

Check parameters match the device
connected

Verify cable is correct

*RS-232 circuits damaged

Display dark, keys
beep

Display contrast poor

Cable unplugged or
damaged

*Check the cables to the display

*Replace the display which could be
damaged

*To be carried out by authorised technicians only.