TestEquity 123HS, Руководство по эксплуатации и обслуживанию

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Chapter 7 – Maintenance
Page 7-4 TestEquity 123HS Temperature/Humidity Chamber
How to Verify the Performance (Non-controlled humidity mode)
These tests verify the performance of the heating, cascade refrigeration mode, electrical controls,
F4/F4T Controller, and air circulation systems. The chamber should meet all published
performance specifications for non-controlled humidity conditions if all of these tests are
successfully passed. These tests assume that the F4/F4T Controller’s setup and tuning values
have not been changed from the values as shipped from TestEquity. Also, the EZ-Zone Limit
Controller high limit must be set to over +85°C (+88°C would be fine), and the low limit set to –
75°C. If the chamber fails any of these tests, it should be removed from service to prevent further
damage until the cause of the problem is determined and resolved.
1. The chamber interior should be empty and at ambient temperature, approxi23°C.
2. Turn ONLY the Power Switch ON.
3. Set the F4/F4T Controller temperature set point to +85°C. Event 2 (F4 Digital Output 2 or
F4T Humidity button) must be Off. Turn the Conditioning Switch ON.
4. The Heat Light should be ON continuously and the Cool and Humidity lights should be OFF.
5. The chamber should heat up to about +80°C and begin controlling (Heat Light cycles
ON/OFF) within 12 minutes. The chamber temperature should slowly increase and stabilize
to +85°C. It should NOT overshoot 85°C by more than a few tenths of a degree,
and the compressors should NOT need to turn ON in order to ma85°C.
6. After stabilization, the chamber temperature should vary no more than ±0.2°C, or a total of
0.4°C.
7. Let the chamber stay at +85°C for two hours.
8. After two hours at +85°C, set the F4/F4T Controller temperature set point to –35°C.
9. The high-stage compressor should turn ON within a few seconds. Then, the low-stage
compressor should turn ON within approximately 30 seconds, the Cool Light should be ON
continuously and the Heat Light should be OFF.
10. The chamber should cool down to about –30°C and begin controlling (Cool Light cycles
ON/OFF) within approximately 45 minutes.
11. The chamber temperature should slowly decrease and stabilize to –35°C. It should NOT
undershoot beyond –37°C, and the compressors should NOT need to turn OFF to maintain
the temperature.
12. After stabilization, the chamber temperature should reach a nominal value of –35°C and vary
no more than ±0.5°C, or a total of 1°C.
13. Set the F4/F4T Controller temperature set point to +23°C. The chamber should begin to heat
up. The compressor should turn off within approximately 1 minute.
14. This concludes the chamber performance verification tests.
15. Let the chamber heat up to +23°C before turning the Conditioning Switch OFF.