Nova-Tech PW Series - Manual (Page 40)

Page 40 of 48
© Adam Equipment Company 2007
Balance is very
unstable and does not
weigh correctly Mechanical problems
Balance programming
Electronic problems
*A complete inspection of the
mechanics to look for sources of friction.
*Verify the A/D is also unstable. If the
A/D is OK then suspect the
programming of the balance. Reset
parameters, check temperature
compensation, and redo the calibration.
Some electronic problems can also
cause this. But all mechanical problems
must be resolved first.
BALANCE IS NOT ACCURATE
You must have accurate and trusted weights to test a balance. If you suspect that the
balance is not accurate then you must know your weights are accurate. A balance
calibrated using a bag of flour is not accurate even if it works OK otherwise.
Balance is not accurate Repeatability
Eccentric loading
Linearity
Verify the balance shows the same
value when the same mass is placed on
the centre of the pan for a few tests.
Verify the balance shows the same
reading (within a tolerance depending
upon the model) when a mass is placed
at positions around the pan.
Verify the balance is acceptable
throughout the weighing range. The
balance must give acceptable readings
from low weights up to the capacity.
Poor Repeatability Usually a mechanical
problem. Inspect the area around the pan for hair,
dust or other obstructions,
*Inspection of the mechanics may be
needed for any possible problems.
Poor Eccentric loading A mechanical problem Inspect the area around the pan for hair,
dust or other obstructions,
*Inspection of the mechanics may be
needed for any possible problems.
*Readjusting of the Eccentric loading is
recommended.