Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

Safe PLC Diagnostic Coverage?

Created by: Aidy Mitton at: 1/23/2014 5:00 PM (3 Replies)

Rating (0)

Thanks 0

4 Entries

1/23/2014 5:00 PM	Rate (0)
Aidy Mitton Posts: 2 Rating: (0)	Hi, Does anybody know the level of diagnostic coverage offered by ET200M CPU (6es7151-8fb01-0ab0)? What is the standard justification for the coverage?
Aidy Mitton Posts: 2 Rating: (0)
Suggestion To thank Quote Answer

1/28/2014 4:02 PM	Rate (0)
SET-Team Bronze Member Joined: 4/17/2009 Last visit: 1/25/2021 Posts: 276 Rating: (50)	Hello, why do you need the DC for the CPU? Normally you don't use the DC for the CPU's, because you should just use the PFHd value for it. Best regards, your SET-team

Suggestion To thank Quote Answer

1/29/2014 12:02 PM	Rate (0)
Aidy Mitton Posts: 2 Rating: (0)	Siemens SET tool relies on set hardware architectures. I have a situation that can not be modelledcorrectly in SET. In this instance I need some justification for the DC value used in my manual calculations.
Aidy Mitton Posts: 2 Rating: (0)
Suggestion To thank Quote Answer

1/30/2014 2:14 PM	Rate (0)
james12 Advanced Member Joined: 6/21/2010 Last visit: 10/19/2020 Posts: 42 Rating: (8)	Hello Aidy, I think isn´t possibleto get an general DC for PLC. Because it is depends on your application. Did you activate F-functionallty or not., How do evaluate the sensors (1oo1 or 1oo2) with or without cross-circut detectionand so on. Basically you need DCto calculatePL or SIL.The PL or SIL is based on PFHd Values. For the PLC as a certified component you have PFHd allready. So you have to calculate the DC for Sensor andReaction and add up the PFHd. Even if you have an complexe architecture e.g. two seperate PLC or other applikations. Okay, lets assume you wouldget an DC fo PLC. What would beyour result for your PLC calculation? With the typical formulas acc. Standards the resultant value is an PFHd.(Is notPL or SIL directly) Now you have a betterPFHd Valuethan Siemens Value for the PLC.My concern ist what is the correctone in case of failure? But that is just a personal opinion. I and hope it helps you to undertand the difficulties regarding DC andelectronic / programmble controller. Best regards James

Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on