Functional Design Specification

[iansmiler]

Hi all, I have to write an FDS for a control system that I am currently working on (Client required ) Could somebody please Email me one that I can tailor to my needs? Many thanks in advance - Ian

[email protected]

 

[cjd1965]

How can you write code if you dont understand the function? Write what you know

Write down how the machine is going to work, what it does, what it doesnt do (exclusions)

Detail sequences .. start,stop,running etc

Detail alarms

Detail interfaces

Detail any parameters

Do you have to provide a HDS and SDS also?

 

[RussB]

You should have gotten this from your customer before you quoted it, may be referred to as 'sequence of operations' or similar which you can summarize with components used to generate your FDS.

 

[kamenges]

Originally posted by RussB:

You should have gotten this from your customer before you quoted it, ...

Generally this is referred to as a URS (User Requirement Specification). This document details what the customer expects the end product to do as well as any specific functions/devices they know they require to make the think work. This is usually where process tolerances and limits are included.

The FDS is produced by the vendor and details in more or less conceptual way how the vendor is going to meet the requirements of the URS. In theory the FDS should lead to the HDS (Hardware Design Specification) and then the SDS (Software Design Specification). However, what often happens if once you get into the FDS the customer keeps on asking for more information in the FDS and you end up with this FDS/HDS/SDS conglomeration.

There is no specific form to an FDS that I know of. As cjd1965 indicated, just write what you know in an organised format and you should be good. Make sure you have someone else read it to make sure the ideas flow coherently. When you are in the middle of writing it you will likely succomb to Scribus Reguritatus (vomited writing) and you will have all sorts of disorganised thoughts in various locations in your document. I would tend to start a little light on detail (stay very upper-level concept) and add detail as requested.

Good luck.
Keith

 

[harryting]

A few years ago ISA put out a sample format and from what I can remember it's not bad.

The typical format I found useful is a short paragraph with general description followed by detailed sequence in table form.

 

[iansmiler]

I have a FDS that I have used to write write the code... I just wanted the format of it to look somewhat professional I was hopeing that somebody out there might have a proffesional looking one that I could steal!!!

 

[jcr]

I have a FDS that I have used to write write the code... I just wanted the format of it to look somewhat professional I was hopeing that somebody out there might have a proffesional looking one that I could steal!!!

Here's a sample. It's a document I did a few years ago. I'm not really looking for any critiques. It is only provided as an example at your request.

I always put my company information and logo in the header. I removed it from the sample provided.

 

[mflaugh]

If you know the pharma industry, there is a set of loosely followed standards called GAMP (Good Automated Manufacturing Process, I believe). Their standards list what they feel should be included in a URS, FDS, SDS, HDS, and other documents used in the lifecycle approach.

I would recommend getting hold of those. Also, related to GAMP is the JETT consortium. A group of healthcare equipment customers / suppliers who worked together to form some sample docs, etc... Those might help as well.

 

[iansmiler]

Perfect!

Thanks all - I am fulfilled

 

[FrancisL]

You might find www.urwwriter.com useful, it is all about specifying user requirements for process automation.

 

[sarfraz_wnv]

http://www.urswriter.com/