Hi,
Last week I faced a problem with a 1756-IF16 analog input module. All the channels being used started showing 15-20% greater values than expected. e.g. two values which should have been zero were around 1000 and varying. I checked the mA at the input (all channels are configured on 0-20 mA and scaled on 4-20 mA). The actual mA on both channels were zero. I changed the IF16 module but the problem persisted. I reset the module using the RSLogix configuration and all values returned to normal. Within a week the problem has appeared again, but this time even the 'Reset module" is not working. The values which should be zero are varying between 50 & 1000 (around 1-20% error) , while the actual mA on the channel are constant at 4mA.
The module is showing a minor channel fault, but that's because of a couple of un-connected channels configured on 0-20 mA. Can it have anything to do with the problem? If not, what might be causing the problem? And what is the solution?
Last week I faced a problem with a 1756-IF16 analog input module. All the channels being used started showing 15-20% greater values than expected. e.g. two values which should have been zero were around 1000 and varying. I checked the mA at the input (all channels are configured on 0-20 mA and scaled on 4-20 mA). The actual mA on both channels were zero. I changed the IF16 module but the problem persisted. I reset the module using the RSLogix configuration and all values returned to normal. Within a week the problem has appeared again, but this time even the 'Reset module" is not working. The values which should be zero are varying between 50 & 1000 (around 1-20% error) , while the actual mA on the channel are constant at 4mA.
The module is showing a minor channel fault, but that's because of a couple of un-connected channels configured on 0-20 mA. Can it have anything to do with the problem? If not, what might be causing the problem? And what is the solution?