SLC5/04

[Guest Mal Dinsdale]

Hi All I have an existing electro-mechanical system that measures temperature via a thermocouple and gives an output 1 to 9 vdc directly proportional to the temperature input. The complete output curve mV input against vdc output is gradually lowered over a period of approx 5 mins, a sort of warm up period. To give an example:- If initially the input was 20mv then the output would be say 6vdc this output would gradually be lowered to say 2vdc over a period of 5 mins assuming that the input remained the same. The ouput does not have to be 1-9vdc as the final actuator could be changed to 4 to 20mA I’m using an SLC 5/04 in 7 rack slot and already contains a thermocouple input module with 6 spare channels so no problem with the hardware my problem is suitable ladder logic that I can use to lower the output gradually over a pre determined time Any help on this would be appreciated Regards Mal Dinsdale

[Guest]

Greetings Mal, here is a "basic idea" program that might help ... if you need more than this, give us some specific details with hardware types and addresses and we'll see what we can come up with ... and don't forget to register on the forum ... hope this helps ... best regards, Ron PS - you can click on the picture to make it bigger and easier to read ... Edited 29 Oct 2004 by Ron Beaufort

[Guest Guest]

Hi Ron, I initially though I had joined this forum some time ago but my name and normal password was not recognised maybe it was a similar forum I joined. I have now joined. Thanks for your input. The ladder logic you have suggested should do what is required. The thermocouple input will be on channel 3 of a 1746-NT8 thermocouple input module located in Slot 03 of a 7 rack module. The output will be to channel 1 of a 1746-NOI located in Slot 04 and configured for 4 to 20mA Regards Mal Dinsdale

[Guest Guest]

Hi Ron, I have just informed you that I have joined this forum, but noticed that my reply still shows me as unregistered. I will check this out. Regards Mal Dinsdale