jjordan

Not that I know of. I had to convert (by hand) every single display item on a HMI to the following syntax. {::[PLC1]N7:83} to dirrectly read a regestry value. Where PLC1 is the device shortcut set up in the communications setup for the project. I am not sure if that syntax would also read a "tag name" in stead of a regester. Some of the real gurus here may have a better answer.

I bought a Current and voltage calibrator from EXTECH. Battery operated, works great for a current or voltage source to test/set-up analog channels. or simulate a process instriment (sp). The batterys go south if you leave it on to long but works great. Around 200 USD. http://www.omnicontrols.biz/merchantadmin/...sp?subcatid=119

Thanks, looks like the CPT instruction mentioned in the referenced thread can be set up as a scaler. I will look into FB / PIDE and see if it seems worth selling as a feature to the end user. Thanks again.

Greetings. I have a project using an Allen Bradley CompactLogix PLC and a PanelView Plus HMI. I will have 4 PID loops with the process variables being monitored by a Ma analog input card. I will also display these on the HMI. Much to my dismay, there is no “scale with parameters” object in ladder logic for RS5000. For ease of maintenance, the end user has requested that I keep as much as possible in the PLC using ladder logic. This kind of precludes going to a function block, STL or HMI expressions. The analog card will do the first “scale” and it seems my main choices are scaled for PID (great for my PID use) or scaled in engineering units X 10 (great for HMI display) Either choice will leave me having to re-scale the data for the other requirement. But then again it appears that the RS5000 PID can do some scaling in that I can specify max/min PV limits in either unscaled analog input units or engineering units X1. Neither of these are my preferred units though. So… I’m thinking of having the analog card scaled for engineering units X 1 and then defining the PID max/min for its use, and just displaying no decimal on the HMI. Or I could pick one and just scale using Scaled value = (input value x rate) + offset Rate = (scaled max. – scaled min.) / (input max. – input min.) Offset = scaled min. – (input min. x rate) I’m not sure of the best approach. This all make any sense? Or am I missing something (wouldn’t be the first time) Thanks.