Why does the motor often trip when starting the booster of the catalytic unit?
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Why does the motor often trip when starting the booster of the catalytic unit? When it’s time to switch the booster pump here, during the process of starting up the backup unit, motor overloading and tripping often occur (at a voltage of 380 volts). A team of field equipment technicians, electricians, instrument specialists, fitters, and others have to work hard for quite some time before things can return to normal operation. Dear sea friends, please discuss what the reasons are
If it’s already said to be overloaded, what other reasons could there be? Our booster has a voltage of 10 KV; isn’t 380 V a bit low? If no technical modifications such as replacing the motor of the booster are carried out, then the next time it is ready to be started, the inlet valve should be opened fully and the relief valve adjusted to a wider opening, allowing the booster to spin up first in order to reduce the starting current. Also, a short-term overload during startup should not cause a tripping, but since you did experience a tripping, it means either the starting current is extremely high, or the startup time of your booster pump is too long. Regardless of the reason, it is recommended that you first check whether the booster pump is stuck or not; if so, identify and resolve the issue. If not, it is recommended to replace the motor; otherwise, problems will arise sooner or later. Personal opinion, for reference only.
It is recommended that you first conduct a \"check\" to see if there are any issues such as the booster not being able to rotate smoothly; this is what is meant by \"turning the machine over.\"
If the inlet valve is fully opened and the vent valve is set wide before starting, a large amount of main air will be vented, affecting the reaction process. Opening the inlet slightly to allow the booster pump to start up can reduce the starting current. Why does it always take a long time for a group of people such as equipment technicians, electricians, instrument technicians, and fitters to get everything running properly? What measures were taken? Perhaps the reason lies there; the issue with the motor could be the main cause
1. The shutdown interlock of the unit has not been reset. 2. The overload protection setting for the motor is too low. 3. There is a problem with the quality of the overload protection relay itself
0. Rotate the turbine to verify whether the unit is operating normally； 1. The vent valve is fully open ； 2. Slightly open the inlet valve to start the unit up ； (Keep the speed as high as possible without affecting the operational process.) 3. Close the inlet valve while starting the motor ； (After the inlet valve is closed, the rotor continues to rotate at a high speed due to inertia) ； Close the inlet valve to reduce the starting load. 4. Once the motor reaches its rated speed, slightly open the inlet valve. Prevent surging (this can be done by monitoring the motor’s ammeter; if the fluctuations are significant, it is necessary to open the inlet valve wider). 5. Increase the load on the booster pump.
This post was last edited by aqhjh0159 on 2010-10-9 at 16:50. 1. Before each startup, the shaft rotation checks out fine. 2. Open the vent valve to about 10%. 3. Slightly open the inlet drain valve to check for water or debris. 4. Open the inlet valve to about 35% and start the motor (rated current: 182A). 5. The instantaneous current exceeds 200; within less than 5 seconds, the motor trips (with the outlet valve still fully closed). Consult technical staff
1. Close the outlet valve completely； Vent valve fully open ； 2. The inlet valve should be opened slowly until the rotor starts rotating and reaches a certain speed ； Starting the compressor rotor first is intended to reduce the motor’s startup time. The motor does not trip immediately when an overcurrent occurs; it trips only after the overcurrent persists for several seconds ； When the motor rotor rotates at a low speed, the current is at its maximum; as the motor speed increases, the current decreases significantly. 3. After starting up, reduce the inlet valve opening ； The purpose is to reduce the inlet flow rate of the compressor. The purpose of fully opening the outlet valve is to reduce the outlet pressure of the compressor. Thereby reducing the starting load of the motor.
Reply to 7# aqhjh0159: Personally, I think the valve for venting is set too small in the startup procedure, while the inlet valve is set too large; this is equivalent to starting the system under load, which will definitely cause a trip
Everyone says the startup method is incorrect; I guess it shouldn’t be that way, as the building manager has been in charge of this for so many years, so it’s probably not a matter of improper operation. 1. Check the distribution room to see if the motor protection current setting is too low. 2. The process interlocks have not been disabled; there is a shutdown cycle interlock in place. 3. Thoroughly examine the interlock configuration to identify any issues. 4. Mechanical failure issues 5. Process operation errors