 SCALE CALIBRATION 
A belt scale should be thought of as a precision instrument, and as such its performance should be quickly and easily checked. Accuracy and the method and frequency of calibration are all directly related.
The generally accepted methods of validating belt scale measurement performance
include;
1. Electronic simulation of load / Shunt Method.
2. Test chain.
3. Test weight.
Although fast, electronic load simulation calibrations do not mechanically exercise the scale. Instead they merely supply a known signal to the scale integrator’s signal conditioning unit in order to check its gain or span adjustment. Although in most cases shunt calibrations are relatively insensitive to
SMALL changes in temperature, it is important to note that shunt calibrations are precisely correct only at the Lab Standard conditions noted on the load cell’s Calibration Certificate.
Conversely, test chain and test weight systems are actual force calibration systems that mechanically exercise the scale mechanism. However, test chains typically require more manpower and time to apply and remove. Also, when
test chains exceed a certain size, motorized hoists are needed to store and apply the chains.
For these reasons, Thayer Scale uses a test weight which represents a specific pounds per foot loading value and an automatic belt length measurement system. Thayer’s unique suspension design assures that the test weight is applied in the same position every time for accurate, traceable and repeatable calibrations free from human error.
THAYER instrumentation provides prompts that guide the operator through the entire calibration sequence. This along with an easy to apply test weight simplifies the calibration process to ensure that calibrations are more likely to be performed on a routine basis. |
INSTRUMENTATION