Motor overcurrent protection circuit sharing

(1) Adjust the resistance of the load resistor Rp1, and the potential of pin 5 will be adjusted. When the current flowing through the motor M exceeds the allowable value, the transistor VT is cut off to ensure that the motor runs within the safe current range.

By appropriately reducing the resistance of R3 and changing the potential of pin 2, the allowable current of the motor can be increased.

(2) Automatic motor overcurrent protection circuit: When the current flowing through motor M exceeds the set value, VT2 is cut off and light-emitting diode VD1 lights up to alarm, thereby protecting the motor.

When the light-emitting diode VD1 lights up to alarm, when the motor current is lower than the set value, VD1 still lights up to alarm;

Increasing the resistance of R6 will reduce the motor overcurrent setting value;

The Rp contact moves upward to reduce the motor overcurrent setting value.

(3) Current overload warning circuit, RL is the load, R4 is a resistor with a smaller resistance. When V1 is not illuminated, if the resistance of RL decreases, the current flowing through increases, and V1 illuminates when it exceeds the set value.

When the current is overloaded, V1 lights up. When the current decreases below the set value, V1 still lights up.

By increasing R4 appropriately, the current setting value can be reduced;

When the current is overloaded, V1 goes out when S1 is pressed, and V1 lights up again when S1 is released.

(4) Overload protection experimental circuit: adjust the resistance value of the load resistor RH. When current flows through RH, the load power supply is automatically disconnected and remains in the disconnected state.

Increase the allowable value of current flowing through RH:

Reduce the resistance of R1;

The sliding contact of Rp moves upward.

(5) Load overcurrent protection circuit: When S is closed, Vcc supplies power to the load. When the current on the load exceeds the rated current, the circuit will be automatically cut off to protect the load.

VD is on, indicating the circuit is working properly;

If the resistance of R5 is increased, the rated overload current will be reduced;

After the circuit is automatically cut off, the circuit cannot restore power on its own.

(6) Motor overcurrent protection circuit.

Adjust the resistance value of the load resistor Rp1. When the current flowing through the motor M exceeds the allowable value, the transistor VT1 is cut off to ensure that the motor runs within the safe current range.

Appropriately reducing the resistance of R3 can increase the allowable current of the motor.