I want to get the status back of the various controllers and CIOC's into our data historian (OSISoft PI) using OPC, but I can't seem to get the comm_alm to read correctly. I can get the main_alm and the failed_alm status using the .CST parameter, but when I try comm_alm.cst for a controller or CIOC then I get an error. Is there more than 1 state for the communications alarm? I have assigned a 2-state digital set in PI which reads 0 or 1, and this works for the maint_alm and failed_alm parameters for controller and CIOC's, but not for the comm_alm parameter; is there more than 2 states for the comm_alm??
Should I be referencing something other than comm_alm.cst (PV.CV for example) or is there something else amiss?
Thanks
Col