User manual

Publication 1760-UM001A-EN-P

Drawing a Circuit Diagram with Pico 4-41

Motor Start/Stop Circuit

A combination of a series and parallel connection is used

to wire a latching circuit.

Latching is established by contact Q1 which is parallel

to I1. If I1 is actuated and reopened, the current flows

via contact Q1 until I2 is actuated.

Logic Table

Latching circuits are used to switch machines on and off. The machine is turned on

when the normally open push button connected to input terminal I1 is activated.

The machine is turned off when the normally closed push button connected to I2

is activated.

S2 opens the connection to the control voltage in order to turn off the machine.

This ensures that the machine will be turned off, even in the event of a wire break.

A self-latching circuit with wire break monitoring can

alternatively be wired using the Set and Reset coil

functions.

Relay Q1 is latched when I1 is turned on. I2 inverts the

break contact signal from S2 and does not switch until S2

is actuated. In this way, the machine is switched off if a

wire breaks.

I1 Start I2 Stop Contact Q1 Coil Q1 Motor

000 0

010 0

111 1

011 1

100 0

I1-I2-------{Q1

S1 make contact on I1

S2 break contact on I2

STOP (S2)

START (S1)

I1----------SQ1

I2----------RQ1