We have an L61 Contrologix processor communicating with a PLC5 remote rack via a DHRIO card. The remote rack has some 1771-IFE analog cards taking mA signals from various flow meters. We are trying to integrate some of the flow signals as pulse outputs are not available, see code below;
This code is based on code from a thread posted previously on this site. We are having two problems, a) there is a 7-8% approx error when compared to local totaliser even when using a constant input, b) the total values seem to stop when they get to 132,000 approx.
The totalisers are in array tags of real type, floating point. Has anybody tried to totalise analog signals in ControlLogix before and if so have they had similar problems. Is there a flaw in the way we are trying to achieve total values. Any suggestions would be appreciated.
This code is based on code from a thread posted previously on this site. We are having two problems, a) there is a 7-8% approx error when compared to local totaliser even when using a constant input, b) the total values seem to stop when they get to 132,000 approx.
The totalisers are in array tags of real type, floating point. Has anybody tried to totalise analog signals in ControlLogix before and if so have they had similar problems. Is there a flaw in the way we are trying to achieve total values. Any suggestions would be appreciated.