So I guess an Uniteruptable Power Supply is useless with a HR21/AM21 combo?

I wonder if the UPS is just on the edge of being able to carry all the equipment and losing the A/C feed caused a slight voltage drop in the UPS. If so, the HR21 might be extra sensitive to voltage fluctuations, thus causing the reboot. If this is the case, you might consider a larger UPS, or take something off of it, like the A/V receiver or TV.

 

My HR21/AM21 combo runs fine on my UPS, I have never had a problem when the power is interrupted.

 

No such problem here...the HR21-200/AM21 combo has never experienced a power related problem since being connected to a decent UPS. (many, many months)

 

Right, but the OP ALSO has his stereo and TV on the UPS. I'm guessing this is beyond what the UPS is rated for too.

 

I had a power outage the other night while I was watching TV & my HR23 & AM21 never blinked, I didn't even know the power was out until I noticed the ceiling fan had stopped moving.

This is the UPS that i have on my system, TV & Receiver included

 

To the OP, what size UPS do you have?

 

I also have an HR21/AM21 combo, and also feed it along with my TV, receiver, and everything else except my sub and shakers. I have no problems during outages. The UPS is rated at 2400va. I tend to turn the big stuff off if the power doesn't come back on fairly quickly, because I don't think the batteries would last very long with that kind of draw, but I've never had any issues.

 

stupid question here, but is the hr21/am21 on the battery side or the surge only side? the apc ups i have only has 1 side that is on the battery back up

 

Me too. I don't have an AM21, but the HR and eSATA have been fine.

On mine, having the TV on reduces the UPS power-back-up time by a *factor of 6*.
If the power goes out for more than just a few seconds, I turn off the TV to get way more power-back-up time.

 

Same here and I have an HR20, HR21, AM21 and an eSATA all on the same UPS. I do not plug my TV and A/V Receiver into a UPS though, just surge.

 

I see what you're saying but I don't see how that would just affect the HR21. If the UPS is overloaded it should affect everything plugged into it.

 

The HR's tend to be quite fussy about low voltage, in my experience.

 

That's why I only buy a UPS with AVR.

 

have 3, 2 hr20 and a hr21/am21 all on ups.. hr21-700 with am21 is on an apc750 and has survived every blink I've had (runs up to 20 minutes with tv on)...
What brand/model do you have?

 

Yes, they are very fussy. Before adding the UPS to my system, the HR20 that I had was the quickest thing to go out when we'd have a low voltage issue. I have a gas range that shuts off gas to the cooktop when it detects a power loss. I thought it was sensitive, but the DVR is even more so.

 

The UPS should be rated to support at least 110% of the full load created by the equipment plugged into it...preferably 125% rating.

I have 4 units in 4 locations, had a number of power-outs.....no problems on any of them whatsoever.

 

You may find that some of your devices don't list VA, but most probably do list watts. Generally watts <> VA (unless you're providing back-up to things like incandescent light bulbs or electric heaters). Add up the wattages of the devices you have, you might want to add a safety factor (20% should be conservative for this purpose), then look for a UPS that can handle that. If you can't find the watt rating of a particular UPS, assume it's about 60% of the VA rating. So, if your devices add up to 1000w, look for a UPS that can handle 1200w, or 2000VA. Hmmm, well, I guess the easy way is just add up your watts and double it for the VA rating.