Preparation Before Calibration: To prevent further calibration errors caused by temperature variations, turn on the new equipment and let it warm up for at least half an hour. This will allow the internal analogue circuitry to fully stabilise thermally.
Create a reference process calibrator that has an accuracy class of at least ±0.01%. As a traceability baseline for accuracy comparison, its accuracy class needs to be at least two classes higher than the new signal generator undergoing calibration.
Make sure all test cables are securely fastened. Make sure there is no electromagnetic interference and that the equipment is consistently grounded.
Full-Range Point-by-Point Accuracy Calibration: Set the output of the signal generator successively to 10%, 25%, 50%, 75%, and 100% of the range. Measure the actual output value point by point using the reference calibrator.
To ensure that the full-range output deviation is below the nominal accuracy of the equipment, eliminate nonlinear variations across multiple ranges by adjusting the gain correction coefficient of the appropriate channel for each range.
Specialised thermal signal calibration: To satisfy the hot runner temperature control channel's verification requirements, temperature simulation signal errors are corrected by point-by-point calibration of thermocouple millivolt output and RTD resistance output.
Verification of accuracy and stability: Following calibration, an hour of continuous operation is carried out, gathering output data from critical verification points every ten minutes to ensure that there is no continuous offset and that the drift during the hour is less than 0.03% of the range.
A full-channel linkage test is carried out while interacting with the hot runner temperature control system to ensure that there are no signal jumps or communication disruptions and that the difference between the temperature control system display value and the signal generator output value is ≤±1℃.
The equipment is prepared for official use once all verification items satisfy the requirements, the calibration parameters are stored in the non-volatile memory of the apparatus, and a calibration record is created and stored.
After replacing new equipment, this calibration procedure may swiftly finish accuracy traceability, guaranteeing the precision of hot runner temperature control calibration and averting further signal variations that might result in injection moulding process flaws.
