Incorrect current conversion on channel (IF16H)

[desa]

Good day. I encountered a problem when calibrating a channel on the IF16H module. The module is located in the local backplane along with the 1756-L73, not a single channel of the module is connected. When I try to set 20mA on channel 3 with a calibrator (YOKOGAWA GA71), the channel goes into error (with a value of 20.58mA), when I set 19mA, the channel shows 20mA. This is not the case with other channels. I can’t go through calibration in the module settings, because the channel cannot receive 20mA, the channel simply goes into error due to exceeding the upper limit.


Thanks for answers.

 

[cardosocea]

Who's supplying the loop? You or the card?

 

[desa]

Who's supplying the loop? You or the card?

calibrator

 

[parky]

sounds to me like the card has some out of spec chips on it, although uncommon Siemens had a problem with a batch of 24v digital input cards, I was doing a project & simulating as much as I could using relays connected to the outputs, r=feeding them back to inputs for valve simulation, the I/O cards were a mixture of old spares we had & new cards, We had a problem that on one of the new cards & sometimes on other new cards nearly all inputs would goe to TRUE, I contacted siemens & they said that cannot happen, we ended up fitting old cards in place of the new cards when on-site so they could be changed later, Turns out siemens eventually admitted that in a particular manufacturing batch some of the chips were out of specification & should not have been released. is it possible you have a faulty card?.

 

[desa]

sounds to me like the card has some out of spec chips on it, although uncommon Siemens had a problem with a batch of 24v digital input cards, I was doing a project & simulating as much as I could using relays connected to the outputs, r=feeding them back to inputs for valve simulation, the I/O cards were a mixture of old spares we had & new cards, We had a problem that on one of the new cards & sometimes on other new cards nearly all inputs would goe to TRUE, I contacted siemens & they said that cannot happen, we ended up fitting old cards in place of the new cards when on-site so they could be changed later, Turns out siemens eventually admitted that in a particular manufacturing batch some of the chips were out of specification & should not have been released. is it possible you have a faulty card?.

yes, that's the same feeling after checking

 

[parky]

Only way to prove it I suppose is if you have another card of the same type i.e. a spare or if there is another one on the system. That would rule out the card it'self.