The motor overload protector can detect the current, voltage and stator coil temperature of the hydraulic oil pump motor. For example, if one of the three types does not work normally, the motor protector will act! These parameters need to be set. Today, Dalan Motor will share with you 10 essential protection principles.
1. Overload protection
When the motor runs under its overload current for a long time and exceeds its rated current, it will cause the motor to overheat. The protector calculates the motor's thermal capacity according to the motor's heating characteristics, and simulates the motor's heating characteristics to protect the motor.
2. Underload protection
When the load carried by the motor is a pump load, the motor will cause harm when it is run without load or underload, and the protector provides underload protection.
Three, blocking / blocking protection
When the motor is started or during operation, if the crankshaft is jammed due to excessive load or its own mechanical reasons, the locked-rotor protection is suitable for protection from such failures when the motor starts.
4. Phase failure (unbalance) protection
The motor is very harmful during phase failure (unbalanced) fault operation. When the motor breaks the phase or the three-phase current is seriously unbalanced, if the unbalance rate reaches the protection setting value, the protector protects according to the set requirements and issues Stop or alarm instructions.
5. Grounding / Leakage Protection
The protector has both ground protection and leakage protection functions. The ground protection current signal is taken from the vector sum of the internal current transformers. It is used to protect the short-circuit protection of the phase wire to the metal shell of the motor. It is mainly used for indirect ground protection to ensure personal safety.
6. External fault protection
When the protector detects that the external fault digital input is inconsistent with the digital input defined by the protector, the protector protects according to the set requirements to ensure the safety of the motor.
7. Start overtime protection
During the motor starting process, the protector only has protection functions such as phase failure (unbalance), grounding / leakage, etc. The rest of the protection functions are not effective. After the start, all protection functions (according to user settings) are automatically activated.
8. Phase sequence protection
The protector with phase sequence protection function shall not operate when the voltage phase sequence of the power supply side is consistent with the set sequence. When the protector detects that the phase sequence of motor d is connected incorrectly, the motor should not start.
Nine, undervoltage protection
If the voltage is too low, the motor speed will be reduced, or even stop running. When the motor operating voltage drops to the set undervoltage protection range, the protector will protect according to the set requirements, and will act within the set time (delay) or Alarm within the alarm time.
10. Overvoltage protection
Excessive voltage will cause damage to the insulation of the motor. When the operating voltage of the motor exceeds the set protection voltage, the protector protects according to the set requirements, acts within the set time (delay) or alarms within the alarm time.
----- Responsible Editor: Dalan Oil Pump Motor 02-Procurement Consultant
Copyright http: / (Dalan Motor) Reprint, please indicate the source
================================================== ================================================== ======
