Design ideas for motor forward and reverse circulation circuits

The motor rotates forward for ten seconds, then reverses for ten seconds, and continues to cycle forward for ten seconds. To design such a circuit, you can first find a similar circuit diagram and combine and modify it based on similar circuits.

 

Since there are motor forward and reverse circuits, similar ones are naturally motor forward and reverse circuits.

 

Button touch contactor interlock motor forward and reverse

 

Select a button operated contactor interlocking motor forward and reverse circuit. Add or modify on this circuit to achieve the required control requirements.

 

The forward and reverse rotation of the motor for ten seconds are similar to the flashing circuit of the indicator light.
Flashing circuit of indicator light

 

The flashing circuit consists of two power on delay time relays, which control the power on time and power off time of an indicator light L.

 

The time for KT1 and KT2 is set to 10 seconds, and the indicator light L forms an infinite cycle of 10 seconds on and 10 seconds off.

Replacing the indicator light with an intermediate relay results in an infinite cycle of 10 seconds of power on and 10 seconds of power off for the intermediate relay.

 

Replace button SB2 in the forward and reverse circuits with the normally closed contact of the intermediate relay.

 

Replace the button SB3 in the forward and reverse circuits with the normally open contact of the intermediate relay.

 

The circuit is basically formed when a motor rotates forward for 10 seconds and then reverses for 10 seconds in sequence. On this circuit, an additional start, maintain, and stop circuit is added to control the start, stop, and voltage loss protection of the circuit.
Starting, maintaining, and stopping circuits

 

By combining the motor forward and reverse circuits, flashing circuits, and start stop circuits for simple modifications, a complete wireless cycle control circuit diagram for 10 seconds of motor forward and reverse rotation is formed.

 

Dual power delay relay control

 

KT2 sets 10 seconds as the forward power on time, and KT1 sets 10 seconds as the reverse power on time.

Press the start button SB2, KM1 will be powered on and the motor will rotate forward. After 10 seconds, KA2 will be powered on and KM1 will be powered off. KM2 will be powered on and the motor will rotate in reverse. After 10 seconds, the motor will stop rotating in reverse and rotate forward indefinitely.

 

Complex circuits are composed of basic circuits, and the accumulation of basic circuits helps in the design of control circuits. The motor rotates forward for 10 seconds and reverses for 10 seconds, which is composed of three basic circuits. The control circuit of a device is usually composed of basic circuits such as the motor rotating forward for 10 seconds and reverse for 10 seconds.

The control circuit of any device is: from simple to complex, from complex to simple.

 

The motor can rotate forward for 10 seconds and reverse for 10 seconds with an infinite cycle circuit, which can be used in some mixing equipment to mix liquids and materials more evenly. It can also be used to control the alternating operation of two water pumps.

 

Continuous cycle time relay

In work, you may encounter some functional electrical components. Using functional electrical components can simplify the circuit and make circuit control simpler. Continuous cycle time relays are one of them.

 

Continuous cycle time relay

The continuous cycle time relay has two sets of time settings. On the left side of T1, after the time is set, timing begins. When the time is reached, the auxiliary contacts begin to operate. The time setting on the right side of T2 is the holding time for the auxiliary contact action. When the time is up, the contact will reset and T1 will start timing again.

 

A continuous cycle time relay is equivalent to a flashing circuit.

 

The continuous cycle time relay must remain energized during operation.

 

Continuous cycle time relay control

 

The T1 of the continuous cycle time relay KT is set to 10 seconds as the forward turn on time, and T2 is set to 10 seconds as the reverse turn on time.

 

Press the start button SB2, KM1 is powered on, the motor rotates forward, and KT remains powered on continuously. The normally open and normally closed contacts of KT release for 10 seconds, act for 10 seconds, and release for 10 seconds in an infinite cycle. Simultaneously control KM1 to power on for 10 seconds before stopping, KM2 to power on for 10 seconds before stopping, and KM1 to power on for infinite cycles.

 

KM1 motor rotates forward, KM2 motor rotates in reverse.

 

Notes in circuit design

 

When switching from forward to reverse rotation of the motor, there will be no short circuit. This is because when the coil of the contactor or relay is energized, the normally closed contact opens first, and the normally open contact closes later.

When the contactor and relay coils are powered off, the normally open contact that operates is released first, and the normally closed contact that operates is released later.

 

When contactors and relay coils are energized or de energized, the normally open and normally closed contacts do not act simultaneously and have a sequential order. Attention should be paid to these details in circuit design.

 

Incorrect circuit diagram

 

The motor rotates forward for 10 seconds and then reverses for 10 seconds with infinite cycles. The circuit diagram above cannot be used. At first glance, it seems that the problem is not significant, but upon closer analysis, it appears that the problem is significant.

Press the start button SB2, KM1 and KT1 are powered on. After 10 seconds, the delay contact of KT1 acts, but the normally open and normally closed delay contacts do not act simultaneously.

 

The delay normally closed contact of KT1 first acts, and then the coils of KM1 and KT1 are powered off. Then there was no more. The coil of KT1 loses power, and the delay normally open contact of KT1 cannot act, so it cannot switch to reverse and there is no subsequent action. (Related fields: electronics, electrical/electrician (exam question bank), communication, maintenance, automation, programming, etc.)