hangzhou mankun imp. exp. co., ltd. , https://www.multihzs.com
Lubricating oil pump outlet pressure is low. The setting value of self-starting switch PSXL-08404 is 0.6MPa. The pressure of the two switches is very close, so when the oil pump outlet pressure switch is slightly delayed, it may cause the first CO2 compressor to jump and then start. Lubricant auxiliary pump.
The short-circuit and disconnection experiments were performed through the instrument switch, and the auxiliary pump started well. By connecting the entire system, it was found that the pressure switch was slow when the pump outlet pressure was low. Checking the switch did not reveal abnormal switching behavior. Lubricating oil pump outlet pressure is low The pressure switch point of the interlock switch is at the outlet of the oil pump. The pressure switch is installed in the switch cabinet. The length of the pressure guiding tube between the pressure taking point is about 8m, and the inner diameter of the pressure guiding tube is small. When the outlet pressure of the oil pump is low, due to the large internal resistance of the pressure guiding tube, the measuring element cannot be depressurized in time, resulting in sluggish switching and a slow response. As a result, the control oil pressure is low and the interlock switch PSXL-08301 moves to make the CO2 compressor jump. .
From the switch setting value, under normal circumstances the lubricating oil outlet pressure is 1.2MPa, the control pressure low switch PSXL-08301 jump value is 0.4MPa, the lubricant pump outlet pressure is low since the start switch PSXL-08404 setting value is 0.6MPa, two switches The operating pressure is very close, so when the lubricating oil pump outlet pressure switch lags slightly, it may cause the first CO2 compressor to jump and then start the lubricating oil auxiliary pump.
Interlocking Improvement Scheme and Effect The key to solving this problem is to reduce the lag in the operation of the low-oil switch and start the auxiliary pump in time. For this reason, we changed the setting value of the switch from 0.6MPa to 0.8MPa. This will not only reduce the lag time of the self-starting switch, but also increase the distance between the interlock jump value and the self-startup value of the auxiliary pump, basically avoiding Jumping switch action phenomenon. Through several years of operation, it was proved that the rebuild was very successful. Not only did the auxiliary pump start to lag, but there was no frequent start of the auxiliary pump.