I’m frustrated

Error Messages in 2704F Temp. Controllers

I got the error messages "Bad NVol CSum" as well as "Module changed" & "Bad Cust Lin" in 1 unit installed on the plant . When checked the other 2 units which i had kept as spare, they were also showing the same error messages.
All configurations that i had made at site, have washed out. So many options are missing for example "Config>Instrument>Options>Programmer>Enable/Disable" has disappeared & "Config>Instrument>Options>No of Loops>shows "0" instead of 1 or 2 or 3 and is not changeable.
Please tell me a solution...
1 person has
this question