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Non-engineer here. Well, not the electrical kind.

About once a week the breaker to my office (read: gamer cave) trips. I just noticed that our 70 inch TV, 2 x Echo Studios, etc. in the living room on the other side of the wall also go out. There's our problem: Two rooms, each with major entertainment systems are both tied to the same breaker. I noticed that when I play computationally expensive games it seems to more often trigger the breaker as my GPU and CPU draw more power, so I wonder: Would some small uninterruptable power supplies between my power strips and the walls for the major power draw appliances potentially fix the issue?

The same way batteries in Satisfactory (simulation game) help my electrical grid not spike above maximum production, by being able to offer energy to spikes while drawing a more consistent amount from the wall.

Is there a certain type of power supply that would accomplish this, while others wouldn't?

JRE
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J.Todd
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    What kind of breaker? At my home I have all outlets 230v@16A = cca. 3.5kW. I don't thin a computer can "eat" all that electricity. – Marko Buršič May 03 '21 at 17:11
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    Sorry should've clarified, it's a (750W) power supply PC, 70 in (110W) TV, Echo Studio sound system (330W x 2), and 1500W heater, which I use even in the summer, might be cold blooded. I'm drawing quite a bit. *Takes trip to breaker box*... Doesn't seem to say the breaker specs on the box. – J.Todd May 03 '21 at 17:40
  • 2nd circuit off of another breaker. – StainlessSteelRat May 03 '21 at 18:40
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    Are you at 110V or 220V or what? And you're saying the circuit breaker has no 5, 10, 15, 20, or 30 Amps rating indicated on it? It's usually molded into the switch itself, but should be there. Perhaps buy a [Kill-A-Watt](https://en.m.wikipedia.org/wiki/Kill_A_Watt) to see how much each contraption is actually drawing? (especially the heater). – MicroservicesOnDDD May 04 '21 at 03:13
  • I don't think a UPS will fix the problem other than keeping everything alive while you reset the breaker. You are just taking too much power from the one circuit. An electrician might be able to come up with a safe, code-compliant fix. Or not. It depends on too many details. – user57037 May 04 '21 at 06:22
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    @J.Todd Note that the "330 W" rating of the sound system doesn't have anything to do with power consumption. It's just a marketing figure ("peak" or "music" power). Actually pumping 300 Watts into a speaker system for any appreciable time would make everyone in your house deaf immediately. (Plus require a whole lot of noisy active cooling to dissipate all the heat.) – TooTea May 04 '21 at 08:00
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    @TooTea Indeed, even the electrical plate on the Echo Studio lists 1.5A max, so no more than 180W each. – J... May 04 '21 at 10:50
  • @TooTea the power rating on a decent HiFi amp may be a couple of hundred W. They tend to use fairly inefficient linear power supplies. However unless being used at maximum output they won't run at this power, so you'[re right. Mine is 2x100W RMS; my speakers can barely handle it, and if I turned it up full blast the last thing the next door neighbours would hear is the screaming (my tastes run to death metal). – Chris H May 04 '21 at 11:03
  • You might also have another 100-200W for monitor(s) and various other bits of hardware associated with the PC and TV setups. These won't help, but won't make a major difference. – Chris H May 04 '21 at 11:04
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    It's the heater. Just move it. The heater takes an entire circuit of its own, leaving room for only a few lights. It also doesn't need an expensive UPS. – Matt Timmermans May 04 '21 at 12:28
  • There are industrial systems that do this. Energy storage inverters combined with a massive battery pack and some control hardware. That's what the Satisfactory game units resemble. They're kind of expensive for non-businesses though. As in, you won't be getting one under 100k and they're the size of a small sea container. Source: I used to work for a company that builds them. – Mast May 07 '21 at 17:54

6 Answers6

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Home UPS aren't designed for peak-shaving. Any system that could do that would have to know what the load is on the entire circuit (i.e. what the rest of the loads are drawing) and then try to supply additional power onto an active bus...you see where this is going. Much easier and very likely cheaper to put in an additional circuit. Do not attempt to replace the breaker with a larger one as this increases the chance your wiring will catch fire.

vir
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A computer + screen + audio should never trip a breaker, you are talking less than 1 kW even with hard out gaming (note: does not include mining). It's your heater... Call an electrician and get another socket in your room on a different circuit breaker or get a heat pump fitted to the bat cave.

Simon
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  • "you are talking less than 1 kW even with hard out gaming" If you add up the wattages of the systems he mentions in his comments, aside from the heater, he's drawing about 1200 W of power. Upvoted for "call an electrician", though. – nick012000 May 04 '21 at 05:31
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    @nick012000 those are marketing numbers. If the sound system actually used full power for some time it would melt and OP would be deaf. – Rokta May 04 '21 at 06:33
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    Cheapest solution.. put the heater on a (good!) extension cord plugged in another room that has its own breaker.. – WooShell May 04 '21 at 08:30
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    @WooShell I'd actually be more inclined to run the smaller stuff off an extension cable, or move the heater across the room if there's a socket there on another circuit. – Chris H May 04 '21 at 10:58
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    @Rokta You don't need to draw full power "for some time" to trip the breaker, a short surge when all components draw the max rated power is enough. Also, who knows what GPU they have, maybe [this one](https://i.pcmag.com/imagery/articles/03BoUhy8xMqGogBqhHxhyDC-3.jpg) /sarcasm – Dmitry Grigoryev May 05 '21 at 11:53
  • @DmitryGrigoryev Not true (unless we're talking about drawing more than 3-5x the rated current of the breaker). A common misconception is to expect a 10A breaker to trip immediately with a 10.1 A load, while in fact it is going to tolerate 20A for like a minute. See for example the [European standard trip curves](https://commons.wikimedia.org/wiki/File:Standard_Trip_Characteristic_of_a_Thermomagnetic_Circuit_Breaker.svg) (the US standards aren't too different). – TooTea May 05 '21 at 12:48
  • @TooTea Another common misconception is to use a regular 10A breaker for a load drawing 20A at startup. Slow-blow fuses exist for a reason. The real point is that we don't know how far from (or above) the limit the OP's breaker current is. – Dmitry Grigoryev May 05 '21 at 13:36
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Some big (>10kW range) full-conversion (read: stunningly expensive!) UPS'es can be programmed to limit the ingress power and to use the batteries to fill the gap between the supply and demand for short periods. Pretty much useful when the whole thing is backed by a generator as well. And pretty much of a surprise when you get a low battery alarm with no single power issue in the last few months.

On the other hand, the usual type of line-interactive UPS for home/office use generally will exacerbate the peak load problem. First, it has its own power consumption of ~3-5% of its rated load and second, it likes to transfer the whole load at once between the batteries and the mains line. It then consumes additional ~10% of its rated power to recharge the batteries.

What can you do:
Get help from an electrician. The problem may be:

  1. a failing breaker
  2. a failing PSU tripping the GFCI because of a developing ground leak (you do have GFCI protection, right?)
  3. a real overload of the breaker, caused by sharing the breaker with unexpected other appliances (like, say a fridge) or the breaker (and the wires!) being too weak for the purposes intended
  4. another problems like arcing somewhere deep in the walls
Makyen
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fraxinus
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    +1 for being the only answer which actually answered the question fully. – JBentley May 04 '21 at 10:31
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    A comment on the question by the OP makes it clear that the issue *in this case* is "a real overload of the breaker, caused by sharing the breaker with --unexpected-- other appliances" (the OP clearly knows the heater is there, so it's not unexpected to them, just to other people reading the question). The OP's comment indicates that there's a 1500W heater being used on the same circuit. – Makyen May 04 '21 at 16:51
  • Are typical home UPSes line-interactive, though, rather than switching over a relay when they need to cut in? Mine (APC Back-UPS Pro 1300) definitely has a relay that makes a big click when it switches to battery power. But its [feature list](https://www.apc.com/shop/ca/en/products/APC-Power-Saving-Back-UPS-Pro-1300/P-BR1300G) also mentions: *Green mode - Patent-pending operating mode that bypasses unused electrical components in good power conditions to achieve very high operating efficiency without sacrificing any protection.* which may indicate that previous models wern't totally passive – Peter Cordes May 04 '21 at 18:14
  • (It also has Boost and Trim features to correct for line voltage without just switching to battery, so it has some capabilities, but could still be switching in a transformer). As a home UPS, I wouldn't be bothered if power was cut for a cycle or so; my computer power supplies have good enough capacitors to not reset the computers. – Peter Cordes May 04 '21 at 18:18
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    I think line-interactive means exactly this - the big relay with its finite switchover time plus some spike filtering and boost/trim. Switching is done in frequency/phase tollerant manner. Offline is the same with less inteligent switching and prone to skipping a cycle or two. Online is a rectifier + inverter always on with a battery in between. The patented bullshit is to disconnect the big iron transformer from the mains when no one needs it, in a way it can quickly engage back without the big "BRRrrrr" as earlier models did. 2 more relays + more logic to control them minus few W standby – fraxinus May 04 '21 at 18:49
  • @fraxinus You're right. I took a broken APC BackUPS Pro 750 apart last year (got bored during lock-down) and that is exactly what I found inside. – Tonny May 05 '21 at 14:22
  • @Tonny yep. I disassembled a number of these with a lot more of a "bored" motivation. – fraxinus May 06 '21 at 07:26
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Your idea isn't going to work. It would work for short-term peak loads (like making toast)... but all your loads are continuous.

Sorry should've clarified, it's a (750W) power supply PC, 70 in (110W) TV, Echo Studio sound system (330W x 2), and 1500W heater, which I use even in the summer, might be cold blooded.

US/Canada power is 120V actually.

So that means 6.25 amps, 0.9A, 2.75A and 12.5A respectively.

Same concept works for other places, just factor for your power (100V Japan, 127V Brazil, 230V most of world).

I'm drawing quite a bit. Takes trip to breaker box... Doesn't seem to say the breaker specs on the box.

It's right on the handle!

It will say 15 or 20. Those are amps.

enter image description here

Amps is current flow. Volts is pressure/"head".

Look at your device's nameplate. Figure out device amps either by

  • reading amps directly off the nameplate or
  • looking for a "VA" figure and divide by 120 volts or
  • looking for a "watts (input)" and divide by 120 volts

VA is an improved "watts" which reflects what loads actually draw in amps.

You could've worked it backwards and multiplied breaker handle x 120 and figured on watts/VA ... either way works. I like amps. Small numbers.

Now, every appliance has an "amps" number between 0 and 12.5.

Write it on the appliance if you must.

Back to the breaker handle. What's the number? Don't exceed it.

Not rocket science, my girlfriend does it every day. "Crock pot 2, heater 12. Want toast (7)? Set heater to low (7)."

Can I upgrade the circuit?

No, but you can add another circuit. Either hire an electrician, or honestly it's possible to learn to safely and legally DIY home electrical. Being an engineer gives you an edge since you have a sharp mind, and NOT being an electrical engineer means you'll accept Code wiring standards without argument (they make no sense to EEs at first; so EEs have a lot to unlearn).

Can I upgrade the circuit to more amps? NO. The breakers protect the wires, and the wires can't handle more amps.

Can I upgrade the circuit to more VOLTS without changing the wires? Maybe. And you'll get twice the practical power if you do. Building codes require 120V sockets in certain places. If you don't nee this circuit to meet that standard, you can simply re-mark the white wire as a ot, change the sockets from NEMA 5-15 to NEMA 6-15, and the breaker to 240V of same ampacity (It's a wider breaker though).

Some things (PC) can run on both 120V and 240V - check the nameplate spec. Others might need a different wall-wart. The heater is not one of them, but, you can easily buy built-in heaters that do run on 240V. They cost $40 and last for 30 years.

Hint: I know you're in North America because a "1500W heater" is defined by a UL spec relevant to 120V wiring. Most UL-spec 1500W heaters have a "low" setting.

P.S. that 1500W heater costs 20 cents an hour to run.

Harper - Reinstate Monica
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  • It might be possible to DIY, but it also might violate local code, and void your insurance. – Scott Seidman May 04 '21 at 22:58
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    @ScottSeidman only in NYC and maybe Boston. Most places, the AHJ provides a mechanism to do it legit, just pull a permit and get inspected. My main stack is diy.se. – Harper - Reinstate Monica May 04 '21 at 23:01
  • Saying "simply change the sockets from NEMA 5-15 to NEMA 6-15, and the breaker to 240V" is, at best, a simplistic wording for what's required to have a 240V circuit with the wires which were used for 120V. It would be *much* better to *at least* say that it's more complicated than you've stated. For example: the 240V breaker won't fit in the same space as the 120V breaker (the 240V breaker will be double the width, and may not be supported by the panel), and the wire which was the neutral needs to be disconnected from the neutral bar, marked, and connected to the other leg of the breaker. – Makyen May 05 '21 at 04:52
  • @Makyen Edited, but none of that is that big a deal, though. I'm not trying to do how-to instructions here. – Harper - Reinstate Monica May 05 '21 at 05:11
  • If the circuit has 12 gauge wiring, it MIGHT be possible to upgrade the circuit from 15 amp to 20 amp service. You'd need to replace all the outlets and switches with 20 amp rated outlets/switches, plus make sure every single wire/box in the entire circuit is rated for 20 amps. This is overall not likely, but it is possible. (12 gauge wire costs more than 14 gauge, plus it's thicker, stiffer, and harder to work with, so unless the homeowner specifically requests it (And pays for it) 15 amp circuits will be wired with 14 gauge wire.) – Duncan C May 06 '21 at 18:45
  • @DuncanC It would all have to be #12. And don't get your hopes up; it's essentially unheard-of for an installer to install #12 and pass up the opportunity to install a 20A breaker on a general purpose circuit. Any general purpose circuit that requires 15A is allowed 20A. Also, 20A circuits are allowed 15A receptacles as long as there's more than one socket. NEC 210.21(B) and a UL White Book rule that requires 15A receps to accept 20A passthru. – Harper - Reinstate Monica May 06 '21 at 20:44
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You comment under the question that you're also running a 1500W heater. I'd be very surprised if that's running flat out; it should have a thermostat that causes it to cycle and maintain a comfortable temperature, and that gives you another option.

In that case a smaller heater would be on more of the time, but drawing less peak current. 300-500W should be plenty to keep the room warm unless you're in the Arctic with poor insulation. It will take longer to warm the room up from cold.

With what's cheaply available to buy here in the UK, I'd get a 750W or 1000W heater with 2 or 3 power settings, using the lower/lowest setting most of the time (somewhere between 250W and 500W probably). The highest setting can be used to bring the room up to temperature quickly if really needed. I suspect it won't be really needed, as (and I'm guessing here) you probably get cold during a long session sitting down - the time it takes for you to get cold gives the room time to warm up.

1500W on 110V is over 13A. With the entertainment kit running another 5-8A (estimated, as in practice you won't use the full rated power) you'd get to 18-21A. At 21A a 20A breaker would take a long time (hours) to trip, if ever. A 15A breaker would still take a while to trip , but a 10A breaker should go fairly quickly. A typical (UK-spec) breaker would give you double the rated current for up to a minute or so; a smaller overcurrent could be maintain for tens of minutes. So I reckon you've got a 10A or 15A/16A breaker, which is little more than enough for your heater - and quite possibly you've got too many sockets run off the one breaker.

Chris H
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  • Standard household breakers have time delays in the UK? In NA, they don't. – Matt Timmermans May 04 '21 at 12:52
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    @MattTimmermans no, they have [trip curves](https://www.electricalclassroom.com/b-c-d-k-and-z-mcb-trip-curves/#1-class-b-trip-curve). Apparently all [UL-rated breakers do as well](https://www.c3controls.com/white-paper/understanding-trip-curves/) though I'm not sure the classes are exactly the same. – Chris H May 04 '21 at 13:02
  • I believe ours are usually just electromagnetic, and don't have that bimetallic strip. At least I've never seen one take more than a second to figure out what it's doing. – Matt Timmermans May 04 '21 at 13:08
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    @MattTimmermans in a short circuit fault, it should be far less than a second. Overcurrent trip can't be instantaneous or many startup currents would be problematic. Loading to 2x rated current would be instructive, but I'm not sure if it's a good idea – Chris H May 04 '21 at 13:23
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    Yes, you're right. Trip curve says it can take 2x for ~10s and 1.2x for ~ 1 minute – Matt Timmermans May 04 '21 at 17:03
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I hit the problem with a powerhouse computer and a room air conditioner--and that was before the days of laser printers. The only solution is what I did--hire an electrician to run another line. Since wire is a tiny part of the cost I had him run a 4-conductor wire instead, I got two circuits out of it so the printer is on a separate circuit from the computer.

Loren Pechtel
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