User manual

Publication 1760-UM001D-EN-P - September 2005

7-14 Retention

Retentive Up/Down

Counters C7 and C8

How the Retention Works

The actual values of counters C7 and C8 are retentive. When the

condition for resetting the counter is satisfied, the actual value of the

counter will be reset.

Examples

Counting Parts

Task 1

Parts are packed automatically in a shipping carton. Even if there is a

power outage, the correct number should still be packed into the

carton. When the carton is full, the carton is removed manually and

the counter is reset.

Contacts and relays used:

Signal diagram:

U = Supply voltage

Coil Function

I5 Count parts

I6 Reset counter

Q1 Carton Full, signal lamp

C8 Up counter

DIR

CNT

RES

{

I5---------CC8

C8---------{Q1

I6-C8------RC8

0042

0036

Circuit Diagram:

Parameters entered: