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zng
February 21st, 2005, 09:24 PM
All,

Can someone please explain to me why I can't load paramater information (e.g. EU of 100% etc) from a FFB device in our system database (offline) to that particular FFB device in the field? It seem as though it has loaded successfully however some parameters (e.g. description) are changed while others (e.g. EU of 100%) are not changed in the field.

If I connect to the FFB device in the field (online), I have no problems changing that parameter on the fly.

Please advice.

Thanks
ZNG
flaviostz
February 22nd, 2005, 06:34 PM
What is the system?

For example, in Smar System302 you can do your configuration off-line, then make a partial download to the devices. Thus updating the devices parameters with the ones in your off-line "database"

Check out System302 at:

http://www.smar.com/system302/index.asp

Remember that there are some parameter that are Read Only and cannot be changed. Others are Read/Write parameters and they can be changed.

Regards,
Flávio.
Georgechu
February 24th, 2005, 08:07 AM
I have seen similar issue with configuring FF devices in DeltaV. The EU must be selected from a short-list provided for a device, otherwise the parameter will not download. I would watch out for typos or slight discrepancies in spelling.

George
jberge
February 25th, 2005, 05:57 AM
_SCALE and _OPTS can only be set when the block is in OOS or MAN mode. Perhaps this is not happening correctly when you download although the host software should really be taking care of that. Other posibilities include the EU mismatch that somebody already mentioned, as well as the values being outside some range or violating some minimum span or other rule. For example, I would imagine that the following scenario could cause problem in some combinations of device and host software: assume the range in 0-100 but you want 100-0 to reverse the action becuse you put your DP back to front. When the system writes the 0% as 100 the device detects that with a lower value of 100 and an upper value of 100 you get a span of zero which is illigal. Same for 100%. Online you can first set one of them to 50 temporarily.