So we just lost power. Tree down at the end of my driveway. Lines down and blew the transformer. So I'm sitting here without power and was watching cyber power do its thing. Was I supposed to turn stove off as soon as we lost power. I just let it run but battery died after about 30 minutes leaving a pot full of smoldering pellets. Just trying to understand how this works
Well it hasn't happened to me yet, but as far as I know the stove is not going to understand that it's on "borrowed time" UPS power. There is no data connection for the UPS to send an instruction to the stove telling it to start it's shutdown sequence, like it would with a PC. I have read various bits and pieces in the past suggesting a Harman stove will "know" it's on UPS power and initiate a self shutdown, but I don't see how that's possible, at least not with my P series stove anyway. I think the UPS is simply giving you time to do a manual graceful stove shutdown on your own, so you don't end up with a pot full of smoldering pellets and potentially a house full of smoke, if your draft isn't great. 30 mins doesn't seem long enough though, mine takes 45 mins to an hour to complete it's shutdown sequence. Anything else plugged into the UPS besides your stove? If you have a generator, the 30 mins does buy you time to get it running, and the UPS plugged into it.
As ttberg said above, the UPS is really only for you to have enough time to do a proper shutdown, not to see how long it will continue burning. I suppose you could time the actual shutdown time needed, and shut it off based on how much time was left on the UPS.
Only thing plugged in was a cell phone charger. Thanks for the info guys. No smoke of any kind present on the p68 which is on the ups. However the advance which is in the basement revealed a couple leaks. This stove is not on a ups and is vented with Selkirk direct temp piping. I see wisps of smoke from the fines box cover and just above it where there is some gasket cement.
sorry, Cork, I dont know what unit you have, buuut, with Harman, and series E revision and later CB's, hooked up to a UPS works like this: As we all know, power coming in is a curved sine wave. When power is interrupted, the "new" power (from the UPS battery), is a sine wave, but square. The CB detects this change, and simply pulses the combustion blower to get the smoke out, so it wont leak into the home. It wont really run the stove....dist fan, feeder, wont run. Im sure someone who knows power will chime in and correct me, but thats it basically. Other stoves....."other" being non-Harman, well, who knows?
I suspected it was looking for the square wave of a typical UPS. however, the CP1500 is a sine wave output, so the Harman cannot tell the change from commercial to UPS power. I to am connected to a CP1500 and would still rather have a 'clean' sine wave to power the system down, and not risk damage to the control board. You will find that plenty of generators do not produce very clean power as well. i've been meaning to grab our old oscilloscope and look at the output of my Generac 8500.
usually a clean sine wave would be nice, but in this case, once the battery crapped out, you might get smoke in the home...so, weirdly, in this case, a square wave, like the APC750 would be better, since it would power the unit down without human assist, in case no one were home. You can turn this feature off though, if you've a generator with a square wave.
My UPS doesn't mind the power from my conventional generator at all. I would think the Harman would see it the same as utility. Anything besides the Harmans mentioned, I would never out the stove on a non sine wave UPS. The motors (ac)especially do not like that form. Sound like crap running on them. I suppose if you have a a stove with dc motors it wouldn't matter.
My Quad doesn't mind the modified sine from my APC but is doesn't like my generator power. I haven't tried my new CP on my genny yet. My pure sine Tripp Lite has no problems with stove or genny.
I also have that cheap Harbor Freight 700w thingy. Nothing really likes that except light bulbs and TV. ( tried it on my little 19" lcd). Plugged it in to my ups when I first got it. Ups lit up the whole lcd in hieroglyphics.
Quad seems to run fine on all of my UPS'..... I don't hear or see anything out of the norm, it just hums along. The APC keeps switching back and forth when on generator. The damm thing just doesn't like that power. That's good to know about the CP. If I get a chance, I may try it tomorrow.
Yeah, no permanent damage done. Bought that on a whim one day. Would only use it in an emergency. I would put the spare board in the West Point and see what happens. Sure hope I never get to that point.
