relays

John, have you looked at those references yet? Do you disagree?

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That'd

Yet again, confusing power gain and energy gain.

There are infinitely many natural numbers. To count them all, it would take forever.

Same thing.

John

That'd

The output energy is the (assume constant) output power integrated over time. The input energy is fixed, just however many joules it took to turn the latching relay on, just once.

If you compute the average power gain over some time period, starting maybe just before the turn-on blip, the Pout is constant, but the Pin declines with time. So the averaged power gain is some constant integrated over time.

All of which indicates that the power gain of a latching relay is different from the power gain of a regular relay.

John

Water power was used to lift and turn things a long time before the steam engine was invented.

John

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That'd

Quit parroting this nonsense and do the math.

John

In article , snipped-for-privacy@highNOTlandTHIStechnologyPART.com says...>

^^^^^^

Including water.

I never said that "a relay" has infinite power gain.

I said that a latching relay has unlimited power gain as the averaging time of the measurement increases. That's one reason why we use latching relays.

And it's a pretty trivial observation to be getting so many people upset.

John

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That'd

Since power is measured in watts (or Joules per second), and should not be confused with work, which is the integral of the power over time, I think that the relay's power gain must be limited by the rating of the contacts, the gain thus being the ratio of that to the actuating current required to change its switching state.

A latching relay that latches once and remains dormant thereafter is no longer an 'active' component; It becomes equivalent to a piece of wire.

Current? Currenyt is neither power nor energy.

Geez, get a life. Or do some math. Or both.

John

Picky picky. Okay, the *power* required to change the state. I think you knew what I meant...

Power can be measured instantaneously, or it can be averaged over time. That shouldn't be controversial.

For a conventional relay, the instantaneous power gain is the same as the longterm averaged gain... just load power divided by coil power. For a latching relay, the math is different. The only reasonable way to measure the power gain of a latching device is to average over time.

Do the math.

But a fathead is always a fathead.

John

OK, now divide both energies by the observation time and the numbers become power.

John

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That'd

Certain parties are now arguing that a quantity that has no upper bound may not qualify as "infinite."

So, given my working-engineer definite of "infinite" as "having no upper bound", a latching relay can have a power gain that, averaged over time, is unbounded, so infinite by my standards.

But really, this was just a curious observation. You've blown it up way more than it deserves, for some reasons of your own.

I like latching relays mostly for their thermal EMF's which (another debate!) are effectively zero. That's because the averaged coil power approaches zero for long observations, which was my point in the first place... Pout/Pin tends to grow as Pin approaches zero. Most of our products aren't especially power-consumption sensitive.

John