Revenue Meter KYZ Pulses

[richanton]

Anyone have any experience with sending utility KYZ energy pulses back to a Distributed Control System. We are hardwired from the utilities meter output to our DCS input card. The pulses seem to work for a few days(I assume acurately) and then it just stops working for a few days, then starts up again.
Since it is intermittent, I can't believe its anything with the programming.

 

[jghrist]

The KYZ pulse outputs are not signals, they are form C contacts. If you have wired them as a voltage or current signal, maybe the wires are picking up enough induced voltage/current to operate as a pulse some of the time.

 

[busbar]

To achieve a degree of reliability, the KYZ interface routinely uses a form-C contact set. Does your DCS I/O look at transition for both contacts? ANSI-grade utility metering components are intended to be very reliable, for potentially large monetary transfers result.

In modern revenue meters, optoisolators are common. It may be that the DCS wetting voltage or input sensitivity is not compatible with the meter pulse output. The next rime it fails, disconnect the meter-to-DCS connection and check the meter side for contact transitions with an ohmmeter set on a low range.

 

[richanton]

The KYZ pulses are connected to a special DCS input card designed to count pulses.

After some discussion yesterday, we think it may be an issue with the software, or possibly the DCS card.

The pulses are sent to the plant and the utility simultaneously. The utility is receiving everything OK, the problem is only at the DCS.

When I get a real answer I'll post it.