Room air conditioner - way to prevent voltage drops?

Get a power conditioner for about 100 bucks from tiger direct or costco. I run my computer on one. When the power drops out or there is a glitch the computer never sees the voltage drop The PCU starts whistling and flashing lights to tell me to turn the computer off in an orderly manner. But I can finish what I am working on before I do. My small unit will run my computer and accessories for about 20 minutes on it's internal battery

Sorry to burst your bubble, but there is no "magic box" that will truly solve your problem (assuming of course that it is a residential type 1 phase AC unit). 1 phase motors need a big slug of power to get them moving. This is done in several different ways, but suffice it to say that they almost all will interfere with any attempts to ameliorate you voltage drop. Be wary of "green plugs" and soft starters that claim they will do this. They can reduce the current surge, but at the expense of starting torque which will prevent it from starting properly and cause damage to your AC compressor. They are also notoriously "noisy" from a power line standpoint and will tax the filtering circuits of your UPS as well. They are not worth the packaging material they come in!

If as you say it is a temporary condition until you move, the UPS solution is probably the best. You may also want to do whatever you can to reduce the load on that circuit while unattended, i.e. turn off the monitors, lights, stereo, etc.

I have a very similar situation, a small workshed that I use as a home office with 2 PCs and a Laptop running. I used to have a Westinghouse AC that drew 1500W and tripped the breaker quite often. I finally replaced it with a small Goldstar energy saver style AC that draws

900W. It can keep up with the PCs heat rejecti>I have a home office with multiple PCs that generate a lot of heat.

No bubble burst.

Thanks for the insight, esp. the info about the boxes that do exist but might do more harm than good.

Yes, it is a single phase AC unit. It is a temporary problem, as I said, because when the basement is finished the office will move down there. I can easily install a second 15a circuit just for the AC...in fact the office is probably going to be in the same room as the breaker box. In the meantime, as long as the UPS does its job I should be OK even if the breaker does trip.

Sounds like your situation is almost identical to mine... 2 systems and a laptop (plus a heat-generating 21 inch CRT). I bought one of the Maytag portable a/c units from Home Depot, 9000 BTU, 8.2A (i think). It works like a champ (except for the light dimming thing). I pretty much leave it off except when I am in the room, and it cools pretty quickly. It even has a remote so I can control it from my desk. I had to get a portable unit due to my HOA covenents and rules about window A/C, but even still I would buy it again due to portability convenience.

On Thu, 06 May 2004 11:58:43 -0400, Billyba put forth the notion that...

There are a couple of things you can do that might help. First, take a voltage reading at your main breaker. Power companies often times fail to keep up with increasing loads on their system. You may be me too far from the nearest transformer, and not getting the full 240 volts to begin with. I had this exact same problem at my house years ago. The voltage was so low, that the compressor motor would overheat and the thermal overloads would kick it off. Once I notified them of the problem, they came out to verify my readings, then added a new transformer at the nearest pole. I haven't had a problem since. The other thing you might be able to do, is replace the wiring feeding the AC unit with larger conductors. Unless it's a long run or the conductors are small to begin with, this approach may not make much of a difference, but sometimes a couple extra volts (if you can get them) is all you need to make a difference.

snipped

Laser printers are pretty hideous. I suggest that your laser goes on a dedicated circuit, 20 amp separate from everything else. We had a office situation with lots of cubes. Most everyone had a laser printer. Since Cubes work on shared circuits especially the neutral it drove us mad. Then we decided on one circuit for each cube and then they shared a single printer. The printer was on its own circuit. Problem solved. Copy machines that are lasers are worse.

Might not hurt to check your grounding at the service. It might be time to test it. Performance grounding is ~

On Thu, 06 May 2004 16:19:13 GMT, "bushbadee" Gave us:

I thought you had a brain, but your top posted response, and the B prefix in you posting header, as well as the basic stupidity of your solution makes many of your previous stupid posts pale, and removes all doubt that you are without one.

On Thu, 06 May 2004 17:01:05 GMT, Bob Gave us:

Top posting retards can solve their basic stupidity problems by BONING UP on Usenet posting protocols.

| I have a home office with multiple PCs that generate a lot of heat. | To help with this situation, I bought a portable a/c unit to help keep | the room cool (at least while I am in there). | | It works very well. However, when it kicks on it really drops the | voltage in the room. I have not yet had a problem as all my PCs are | plugged into UPSs that compensate for this sort of thing, however, I | am afraid that my circuit breaker might trip one day when I'm in the | middle of work. | | So I'm wondering if there is a device that can be plugged in between the | wall and the a/c unit to feed it the juice it needs when the motor | starts and prevent voltage dips? And if so can someone point me to a web site | or tell me where to get it?

Plugging in between the wall and the A/C unit won't help unless it is a very expensive power storage device. A power conditioner will just make sure the A/C unit gets full voltage (which it doesn't exactly need at that instant), and really will just dim your lights (and voltage to computers) even more. It still has to suck power out of your circuit. A rather massive UPS for the A/C unit would work, but it's going to need to be rated for the starting current, which could be several times the normal running current (we're talking 2 to 10 kVA costing $1000 to $6000).

A power conditioner on the computers would be better. But keep in mind that boosting a low voltage increases the current and thus increases the chance of tripping the circuit. If your computers have a lot less load than their power supplies are rated for (such as 50 watts on a 300 watt P/S) then they should handle those low voltage dips fairly well even without the UPS. If your UPSes are correcting voltage (not all do), then you really having nothing to worry about but the circuit breaker tripping out. And keeping you loads lower helps (including _not_ trying to boost the voltage).

| I know the best solution is to run a separate circuit but my office will | eventually be moving to another room.

To prevent the circuit breaker from tripping, this is what you will need to do, or else cut back on other loads. Any PCs you can move to another room and use them remotely? Any lamps you can eliminate? Can you get by with a smaller A/C unit? Do you have a 2nd monitor that does not need to stay on?

You might expedite that move, after getting a dedicated circuit put in over at the new room for the A/C.

| PS - is there another group that would be better for posting this question?

The people that know tend to hang out here, so I think it's OK.

I hope you are dumping the hot air and water out appropriately. I've seen more than one person who thinks that an A/C standing in the middle of a room with only power connected to it will somehow cool the room.

Your wrong. I have designed many APU that switched from line to battery with out the load ever knowing what happened, even ones that worked with 3 phase power.

In fact some run off the battery 100% of the time and only use the line to keep the battery charged. All the Minute man perimeter defence power supplies work this way.

I have a 600 va unit that runs my whole system It costs just a hundren bucks at costco. You can also buy one from Tigerdirect. They have batteries in them. If the line drops, the battery takes over. The computer never realizes there has been a power drop out I have printers, scanners, computers and a host of other objects on it. It gives me about 20 minutes of use and if the power drop out is longer than that, it begins the orderly turn off of the computer.

| I have a 600 va unit that runs my whole system | It costs just a hundren bucks at costco. | You can also buy one from Tigerdirect. | They have batteries in them. | If the line drops, the battery takes over. | The computer never realizes there has been a power drop out | I have printers, scanners, computers and a host of other objects on it. | It gives me about 20 minutes of use and if the power drop out is longer than | that, it begins the orderly turn off of the computer.

With so much on it, are you sure it will last 20 minutes? Sounds like a lot for a 600 VA unit.

If it works, it should ride you through the A/C unit tripping the breaker if you go reset that breater soon enough. As for low voltage, it depends on the settings (probably factory set).

|> A power conditioner on the computers would be better. But keep in mind |> that boosting a low voltage increases the current and thus increases the |> chance of tripping the circuit. If your computers have a lot less load |> than their power supplies are rated for (such as 50 watts on a 300 watt |> P/S) then they should handle those low voltage dips fairly well even |> without the UPS. If your UPSes are correcting voltage (not all do), |> then you really having nothing to worry about but the circuit breaker |> tripping out. And keeping you loads lower helps (including _not_ trying |> to boost the voltage). | |