In the environmental test, if the high low temperature test chamber low temperature can not stabilize how to do?
High low temperature test chamber low temperature stability of the failure analysis: first observe the high and low temperature box refrigeration compressor in the high low temperature test chamber can be started during the operation, if the high and low temperature box compressor in the course of operation can start, Power to the high and low temperature box compressor electrical lines are normal, electrical system is also no problem. When the high and low temperature box electrical system is no problem, then continue to check the refrigeration system. If the low-temperature (R23) class compressor exhaust and suction pressure are lower than normal and the suction pressure is evacuated, it means that the cooling of the main cooling unit The dose is obviously insufficient. And then touch the high and low temperature box of the host group R23 compressor exhaust and suction lines, such as the exhaust pipe temperature is not high, the suction pipe temperature is not low (not frost), which Also describes the lack of R23 refrigerant in the host group. One of the high and low temperature test chamber is the main unit and the other is the auxiliary unit. When the cooling rate is large, the two groups work at the same time. At the beginning of the temperature holding stage, the two groups still work at the same time. To stabilize the temperature initially, the auxiliary unit to stop working, by the host group to maintain the temperature of the cooling and stability. If the host group R23 leak, will make the cooling effect of the host group is not large, due to cooling process, the two units at the same time work, so there is no stable temperature of the phenomenon, and instructions to reduce the cooling rate. In the temperature holding stage, once the auxiliary unit to stop working, the host group and no cooling effect, high low temperature test chamber air temperature will slowly rise, when the temperature rises to a certain extent, the control system will start the auxiliary unit to cool, and then Auxiliary units and stop working, so repeated, there will be low temperature can not hold the fault phenomenon.
High low temperature test chamber maintenance methods: high and low temperature test chamber of the refrigeration system leak detection, with a leak detector and soap and water combined method to check where the leak, if found to be hot gas bypass solenoid valve stem split There is a slit, then replace the solenoid valve, such as the discovery of other parts of the leakage, then the use of oxygen welding will be full of welding, and then re-filling the system, the system can be restored to normal operation.