I. Preparation and Self-Test Before Calibration
Start all hot runner signal generators and preheat for at least 30 minutes to allow the internal crystal oscillators and circuits to reach thermal stability.
Enter the device's "System Settings" menu and perform a system self-test to confirm that all channels have no hardware errors and the device is functioning normally.
Disable AM, FM, and other modulation functions on all channels and uniformly select a standard square wave/sine wave as the output waveform to avoid additional signal interference during the calibration process.
II. Reference Channel Locking
Confirm that the master signal source clock is set to "Internal," serving as the sole time reference source for the entire system. Lock all slave signal source clocks to "External," forcing them to follow the master clock.
Measure the output frequency of the master channel using a high-precision frequency counter to confirm that the master clock reference deviation is ≤ ±1ppm, ensuring the accuracy of the calibration reference itself.
III. Single-Channel Deviation Point-by-Point Calibration
Using the rising edge of the master channel's output waveform as the reference, simultaneously acquire the output signals of the master channel and the first slave channel using an oscilloscope, and read the phase time difference between the two signals.
Enter the "Delay Calibration" menu for the slave channel and fine-tune the channel delay correction coefficient until the rising edges of the two signals are perfectly aligned and the deviation is zero.
Repeat the above operation to complete the deviation calibration of all slave channels one by one, covering the commonly used output frequency bands of all channels, with a focus on calibrating the 1kHz and 10kHz frequency bands commonly used for hot runner calibration.
IV. Amplitude and Link Compensation Calibration
Set the output amplitude of all channels to 1Vpp, commonly used for hot runner calibration. Use an oscilloscope to measure the actual output amplitude of each channel. If the deviation exceeds ±1%, adjust the gain correction value of the corresponding channel to eliminate the indirect synchronization error caused by the amplitude deviation.
If the synchronization trigger line length exceeds 200 meters, enable the device's cable resistance compensation function. The transmission delay compensation amount will be automatically calculated based on the cable length and cross-sectional area to offset the synchronization deviation caused by long-distance transmission.
V. Full-Channel Synchronization Verification
After all channels are calibrated, use a multi-channel oscilloscope to acquire the output waveforms of all channels at once to confirm that the synchronization deviation of all channels is ≤0.01s.
Run the multi-channel synchronous output continuously for 30 minutes, collecting synchronization deviation data every 5 minutes to confirm there is no loss of synchronization due to drift over time.
VI. Parameter Consolidation: Access the Utility menu of all signal generators and save the calibrated delay correction coefficients and gain correction values to non-volatile memory. These parameters will not be lost after a power outage and restart.
Record all parameter values from this calibration to generate a calibration file. Subsequent periodic recalibrations can directly compare parameter changes, proactively predicting deviation risks caused by hardware aging.
This calibration procedure is fully adaptable to hot runner industrial field maintenance scenarios. The operation process is clear and practical, enabling rapid high-precision calibration of multi-channel synchronization deviations.
