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Edited by Taesungtech at 2019-7-10 14:36
Hello,
Yesterday I just received HT824 Process Calibrator.I tested HT824 and I found some accuracy issues.
Fluke 726 Precision Calibrator and Fluke 89 DVM was used for measurement. (Calibrated befor 8 months)
1. mV output accuracy test :
When set to 0mV output
- LCD backlight Off, DC adaptor disconnected : -0.088mV (0.098%) -> Not accptable
- LCD backlight Off, DC adaptor connected : -0.090mV (-0.1%) -> Not accptable
- LCD backlight On, DC adaptor disconnected : -0.017mV (0.019%)
- LCD backlight On, DC adaptor connected : -0.051mV (-0.057%) -> acceptable
[size=13.3333px]When set to 10mV output
- LCD backlight Off, DC adaptor disconnected : 9.913mV (0.097%) -> Not accptable
- LCD backlight Off, DC adaptor connected : 9.909mV (0.101%) -> Not accptable
- LCD backlight On, DC adaptor disconnected : 9.981mV (0.02%)
- LCD backlight On, DC adaptor connected : 9.949mV (0.057%) -> acceptable
When set to 90mV output
- LCD backlight Off, DC adaptor disconnected : 89.909mV (0.101%) -> Not accptable
- LCD backlight Off, DC adaptor connected : 89.909mV (0.101%) -> Not accptable
- LCD backlight On, DC adaptor disconnected : 89.987mV (0.014%)
- LCD backlight On, DC adaptor connected : 9.945mV (0.061%) -> Not accptable
2. RTD Ohm output accuracy test :
When set to 5.0ohm output (minimum of 5-400 ohm range)
- LCD backlight Off, DC adaptor disconnected : 4.93 (0.017%)
- LCD backlight Off, DC adaptor connected : 4.92 (0.02%)
- LCD backlight On, DC adaptor disconnected : 5.14 (0.035%)
- LCD backlight On, DC adaptor connected : 5.06 (0.015%)
When set to 400.0ohm output (maxium of 5-400 ohm range)
- LCD backlight Off, DC adaptor disconnected : 400.23 (0.057%) -> acceptable
- LCD backlight Off, DC adaptor connected : 400.22 (0.055%) -> acceptable
- LCD backlight On, DC adaptor disconnected : 400.62 (0.155%) -> Not accptable
- LCD backlight On, DC adaptor connected : 400.51 (0.127%) -> Not accptable
When set to 90mV output
- LCD backlight Off, DC adaptor disconnected : 89.909mV (0.101%)
- LCD backlight Off, DC adaptor connected : 89.909mV (0.101%)
- LCD backlight On, DC adaptor disconnected : 89.987mV (0.014%)
- LCD backlight On, DC adaptor connected : 9.945mV (0.061%)
3. Summary
- When using mV output : LCD backlight ON, DC adaptor disconnect
- When using RTD output : LCD backlight OFF, DC adaptor doesn't matter
- Does HANTEK have a plan for firmware update about this accuracy issues?
- If you have a plan, when?
- Is there a way for the user to calibrate HT824?
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