# KYZ relay contacts on meter?

Discussion in 'Home Power and Microgeneration' started by William P.N. Smith, Jan 15, 2004.

1. ### William P.N. SmithGuest

I've got an electrical KWHR meter with "KYZ" pulse outputs every 10(?)
watts, what exactly does that mean? Is it just NO, C, NC, or
something more exotic?

Thanks!

2. ### SQLitGuest

KYZ in my experience has always been open closed for a time then off again.
Sort of like a square wave.

You estimation of the 10 watts I would bet is wrong. I have used KYZ as kwh
and kwdemand. The scaling I have seen is something on the order of 1000kw
to 10000 kw. You will need a pretty fast, nothing exotic real time clock to
count the pulses. The speed at which the pulses come in can vary. Some time
the amplitude of the pulse makes a difference.
Have fun with your new toy

3. ### William P.N. SmithGuest

I didn't really say that, did I? 8*} I meant 10 watt-hours, I think.
It's a GE KV2 meter if that matters...

4. ### SpiderGGuest

According to the Edison Electric Institutes 'Handbook for Electricity
Metering':
"The output pulses are normally Form C closures, commonly known as KYZ or
double throw, single pole or their electrical equivalent. each closure is
one pulse."
"... in a receiving instrument which counts the number of pulses, this
count, multiplied by the primary watthour constant, gives the value of the
energy measured."

It is typically used in remote telemetry or totalization implementations
(sub-metering for example).

The text goes on for another page, but I'm not a goot typist...

HTH
Glenn

5. ### William P.N. SmithGuest

Ah, OK, so it's SPDT, so if it's really relay based you can easily do
switch debouncing. I was afraid it was some wierd quadrature thing so
you could tell which way the energy was flowing, which would be more
difficult to count.

Thanks!