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S5 to S7 conversion project.

A major paper processing plant experienced problems with an old/outdated S5 PLC system. The system was an S5-95U CPU with a large amount of I/O. The existing system was difficult to troubleshoot and not easy to maintain. Fast Automation was contracted to upgrade the system to a new and serviceable system but at a minimum cost.

Existing System:-
G:\DCIM\103NCD80\DSC_0528.JPG

Existing Rack Components:-

Part No.

Description

Qty

6ES5103-8MA12

SIMATIC S5  CPU 103

1

6ES5470-8MA11

Analog Output Module - 2AO

1

6ES5385-8MA11

Down counter with 2 Channels up to 500Hz

1

6ES5421-8MA12

Digital Input 8x 24V DC

11

6ES5441-8MA11

Digital Output 8x 24V DC 1A

8

At first glance not an obvious choice but the Siemens ET200s was selected as the platform solution. Fast Automation believes the Siemens ET200S IM151-7 CPU is a hard option to look past, for smaller Siemens S5 upgrades.

Summary of ET200s suitability factors:-

  • Processing power is not a real requirement when upgrading the S5-95U, most modern small PLC’s will outperform it. IF using the ET200s CPU’s
  • The memory requirement is minimal
  • The I/O can be selected to match card for card upgrading which minimizes drawing changes.
  • The footprint is exceptionally small and therefore can usually be mounted alongside the old PLC without the need for existing cabinets.
  • Spares are readily available, and the system is hot-swappable and low power.

New Rack Components:

Order number

Designation

Quantity

6ES7131-4BF00-0AA0

Electronics module, 8DI, 24 V DC, standard (1 unit)

14

6ES7132-4BF00-0AA0

Electronics module, 8DO, 24 V DC/0.5A, standard (1 unit)

9

6ES7135-4FB01-0AB0

Electronic module, 2AO, U

2

6ES7138-4DE02-0AB0

1 Count 5V/500kHz, connection for RS422 incremental encoders

 

6ES7138-4CA01-0AA0

PM-E DC 24V power module for electronic modules, with diagn.

1

6ES7151-7AA20-0AB0

IM 151 – 7 CPU

1

6ES7193-4CA40-0AA0

Universal terminal module; screw connection (5 pcs.)

5

6ES7193-4CD20-0AA0

Terminal module for AUX1 supply; screw connection

3


New Rack Image:

The difficulty with upgrading S5 to S7 is often that the machine needs to maintain it’s operation throughout the upgrade or have a limited downtime. One technique Fast Automation has developed for minimizing the downtime is to utilize plug in terminals as shown below:-
22760_1000_int_01.jpg22721_1000_int_01.jpg

The process can be divided into the following steps:
Step 1:  The existing PLC is prewired to go through these small plug terminals, and tested/left in production.
Step 2: The new PLC is then prewired with plugs to suit.
Step 3: The new PLC is mounted ready for cutover.
Step 4: Cutover, the old PLC is unplugged the new PLC is plugged in, tested and production continues safe that if any issue is encountered a rollback can be performed in minutes.

Picture of old PLC unplugged while the new PLC is trialed (Please note: aesthetics aren’t so important during this temporary trial period):-
DSC_0186.JPG
Step 5: After a period of testing and “comfort” the old plc is removed at a convenient time.
Below is a picture of the removed PLC (including plug in connectors) from this project.

The before and after shots:-
Before:                
G:\DCIM\103NCD80\DSC_0497.JPG

After:
G:\DCIM\100NCD80\DSC_0294.JPG

 

The project was executed without downtime and in cutover execution, a rollback was not required. However, the option (to rollback), reduced the pressure on everyone and helped facilitate a relaxed productive commissioning phase.

For further information please contact Fast Automation’s David Askew 0418 239 340 or email info@fast-automation.com

43-51 College St Gladesville, NSW 2111, Sydney, Australia     |     +61 (4) 1823 9340     |     info@fast-automation.com