# ABB ACS600 display panel issue



## erics37 (May 7, 2009)

Went for a service call at a wastewater pump station today.

It has three identical 150 hp pumps operating at 480V. Drives are ACS600s, installed about 14 years ago. Unless there is high flow, typically only one pump runs at a time, generally around 40 Hz. Controlled via pressure transducer and PLC, pump speed reference is a standard 4-20 mA to analog input on the drive. Each drive has its own 4-20 pair and they aren't directly slaved to one another.

Here's the issue:

Normally, whichever drive is running at whatever speed the PLC tells it (operating in scalar mode), the display panel shows the following items:

Frequency reference
Actual running Hz
Actual current
Actual RPM

However on one of the drives, the frequency reference display appears to get "stuck" at whatever the last operating reference was. The other drives, even when not running, display a continuously updated Hz reference (you can see it fluctuating up and down a few decimal points). When the problem drive is commanded to run, then it updates its display and operates normally. Switch it back off and run another pump, and the reference value gets "stuck" again. The display on the others will adjust with their analog input even when they are just standing by.

Unfortunately I can't access the entire Parameter list from the keypad (specifically Parameter Group 2) to see if anything got changed. It only gives me access to the more commonly used parameter groups (10, 11, 20, 99, etc). I imagine I'd have to plug in a laptop with some software or something to access the entire parameter list.

Sorry for the long read. Any ideas?


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## Cow (Jan 16, 2008)

http://www05.abb.com/global/scot/sc...56def0049196e/$file/EN_600stdprg_FWmanual.pdf

Looking through this manual, page 4-2, it looks like you want to look at Group 1 Actual Signals, either 19 or 20 depending on which analog input you're using to see if the drives sees the 4-20ma change.

I looked but couldn't find the parameter that unlocks all the rest of your parameters. I've worked on these older drives a little bit off and on, it seems every time I have to work on one I always have to bury my head in the manual ahead of time to even know where to start. I'm not a big fan of those older ABB's...they definitely aren't as user friendly as the newer stuff for me.

When all else fails, you might be able to do a HIM copycat if all the drives are the same.

Don't forget, there is always ABB tech support too. I've called them before on those older drives and they were still able to help me.


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## erics37 (May 7, 2009)

Cow said:


> http://www05.abb.com/global/scot/sc...56def0049196e/$file/EN_600stdprg_FWmanual.pdf
> 
> Looking through this manual, page 4-2, it looks like you want to look at Group 1 Actual Signals, either 19 or 20 depending on which analog input you're using to see if the drives sees the 4-20ma change.
> 
> ...


Thanks for the info :thumbsup: Yeah I really prefer the assistant control panels that have a nice big easy to read screen.


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