UPS for power

[tweiss3]

I have numerous 10500VA power UPS for delicate electronics throughout the house. I've been thinking about it, and the one I use has brownout protection in it as well.

I remember when looking at the warnings, it said do not connect a laser printer, as it could damage the UPS (probably on power draw). Do you think the same applies to my radio equipment power supplies? The largest draw I have is my HF rig when turned all the way up to 100W.

I was looking for a little better protection plus it would be nice to have some battery backup in a power outage situation. Am I worried about nothing?

 

[N5XPM]

As long as the transmit current doesn't exceed the UPS capability, can't see why you wouldn't want the surge protection and battery backup.

 

[a417]

inrush current for some laser printers and heating up the fuser can be 7x the operating current. Unless your UPS is specifically designed to handle a laser printer, you will see that warning.

I thin you will be fine with a 100w radio.

 

[tweiss3]

I'm sorry, my concern is about damaging the UPS. My power supply is 30A DC, which I think is 6-7A AC.

I was unaware laser printers had inrush currents, which would make sense. I think the above comment answered my question, thanks.

 

[littona]

Yeah, you're good. We install small UPS devices at several of our radio sites, some on control stations, some on repeaters. Never had any issues except for when the batteries got old!

 

[spanky15805]

A couple of 12v car batteries in parallel for the radios with trickle chargers might work too.

 

[cmdrwill]

You do NOT want "car batteries" in your house. Also "car batteries" in parallel will drain each other.

Battery 101.

 

[belvdr]

You do NOT want "car batteries" in your house. Also "car batteries" in parallel will drain each other.

Battery 101.

I always thought that too but one of the larger UPS systems I supported some years ago used automotive style batteries in parallel. There must have been some circuitry to prevent that from occurring.

 

[spanky15805]

belvdr...Yeah cmdrwill is telling not to use the flooded style battery. AGM's and VRLA are used extensively in UPS/PCS systems and the style tweiss3 probably has in his UPS is a sealed battery, literally. 12volt, 7 amp hour is a really common size for use in a small UPS. You might have seen a Deka HR5500 series battery?

 

[wa88it]

Interesting this subject shows up as we lost power today for 40 minutes during the tropical monsoonal rains from Sandy today...as i examined my 1kv apc ups and pondered their battery sustainability after years of sitting in a corner gathering loads of dust/crud/ on their surfaces quietly doing their job.

went looking for load test and APC recommended checking fully charged ups unit with a 1k hair dryer until it dies...4+ minutes means your good...

All of mine failed at about the 2 minutes timeframe...sigh!

new batts @ +/- 65$...new acceptable units cost 149$ at sam’s - - tomorrow’s adventure...

 

[n5ims]

What battery do you need where they charge $65 each? I see many in the $25 - $35 range for the typical ones my APC units use. This includes the battery recycle fee. Most of these are the AGM type 12v 8AH to 12v 12AH types. These are ones I can pick up locally so there's no shipping, but includes our local sales tax so that should be a wash.

 

[wa88it]

What battery do you need where they charge $65 each? I see many in the $25 - $35 range for the typical ones my APC units use. This includes the battery recycle fee. Most of these are the AGM type 12v 8AH to 12v 12AH types. These are ones I can pick up locally so there's no shipping, but includes our local sales tax so that should be a wash.

APC Replacement Battery Cartridge #162 - APC USA 69.99$/each + tax & takes two...

new apc ups at sam’s club 149$ + tax or 9 bucks more and smidge of payment goes into the kitty to pay membership renewal!

Olde unit to the local dump no recyle fee...

 

[mmckenna]

If you want to run radios, you'd do better keeping it all 12 volts as far as you can.

AC from the wall gets rectified to DC for the batteries. DC from the batteries gets inverted back to AC to your power supply. Power supply rectifies it back to DC for your radio. AC -> DC -> AC -> DC

You can skip a lot of the inefficiencies by using a power supply with a battery revert module. With a reasonable size battery you can run your stuff a lot longer that way.

Unless, of course, you are trying to run other stuff that only has an AC supply.

 

[buddrousa]

Hooking up 12 volt car batteries in parallel pulls the load even off each battery. OHMS law DC in parallel VOLTAGE STAYS THE SAME CURRENT ADDS 6 12 volt 1000 amp batteries in parallel = 12 volts at 6000 amp capacity.
My firetruck has 6 12 volt batteries in parallel from the factory
My UPS has 8 12 volt batteries in parallel from the factory
I think the design engineers know what they are doing.

 

[tweiss3]

If you want to run radios, you'd do better keeping it all 12 volts as far as you can.

AC from the wall gets rectified to DC for the batteries. DC from the batteries gets inverted back to AC to your power supply. Power supply rectifies it back to DC for your radio. AC -> DC -> AC -> DC

You can skip a lot of the inefficiencies by using a power supply with a battery revert module. With a reasonable size battery you can run your stuff a lot longer that way.

Unless, of course, you are trying to run other stuff that only has an AC supply.

Agreed, that would be less loss and more efficiency. My real goal was to get the equipment on surge protection, instead of the cheap power strip it is currently attached to. For only a few bucks, you can add power backup, and the more I thought of it, the more I liked the idea of having some power to get radio communications out in the event of an extended power outage (other than jumping in the car or grabbing an HT).

Edit: the UPS has simulated sine wave output and brown out protection, which I really like.

 

[a417]

Edit: the UPS has simulated sine wave output and brown out protection, which I really like.

You know that simulated sine wave isn't that great, right?

Here's cyberpower's take on it.

Here's a page from Minuteman...

Good 'ol Tripplite has an opinion, too.

Granted they're all heavily biased towards selling you more expensive things (that consequently do better with delicate equipment), but simulated sine wave output (while your systems are actively on it, and not running off the mains) causes trouble. Newer Macs don't like it, anything that has newer Active PFC circuitry might have issues with it, it's a crap shoot. YMMV.

These issues might not even cause you a moment of concern based on your local implementation, but please don't fall victim to marketing wank.

 

[chief21]

I liked the idea of having some power to get radio communications out in the event of an extended power outage

You do realize that most UPS devices will provide power for only a relatively short time? These devices are intended to bridge momentary power glitches and short drop-outs or, in the event of longer outages, to allow one to power down electronics properly. Depending on the model, the load, and the age/condition of the batteries, they might provide anywhere from a few minutes to perhaps 30 minutes of backup.

 

[tweiss3]

You know that simulated sine wave isn't that great, right?

Here's cyberpower's take on it.

Here's a page from Minuteman...

Good 'ol Tripplite has an opinion, too.

Granted they're all heavily biased towards selling you more expensive things (that consequently do better with delicate equipment), but simulated sine wave output (while your systems are actively on it, and not running off the mains) causes trouble. Newer Macs don't like it, anything that has newer Active PFC circuitry might have issues with it, it's a crap shoot. YMMV.

These issues might not even cause you a moment of concern based on your local implementation, but please don't fall victim to marketing wank.

That's good information. Thanks. I currently have 3 desperate Cyberpower towers at my house and have had great luck with them. I get 3-4 hours backup for my internet, 4 hours for my camera system and about 15 minutes on my workstation (enough for it to auto shutdown/hibernate).

You do realize that most UPS devices will provide power for only a relatively short time? These devices are intended to bridge momentary power glitches and short drop-outs or, in the event of longer outages, to allow one to power down electronics properly. Depending on the model, the load, and the age/condition of the batteries, they might provide anywhere from a few minutes to perhaps 30 minutes of backup.

It doesn't need continuous power. The radios are normally off and wouldn't drain in a power outage until I turned them on. The idea is in an extended outage, flip one radio on for short use, then back off it goes.

 

[mmckenna]

Edit: the UPS has simulated sine wave output and brown out protection, which I really like.

Yeah, if 'simulated sine wave" is anything like "modified sine wave", there's a reason the UPS is cheap.

May work just fine for your application, may not. I've had network switches at radio sites that didn't like the modified sine wave inverters. Had to upgrade to pure sine wave equipment.

 

[a417]

Yeah, if 'simulated sine wave" is anything like "modified sine wave", there's a reason the UPS is cheap.

May work just fine for your application, may not. I've had network switches at radio sites that didn't like the modified sine wave inverters. Had to upgrade to pure sine wave equipment.

Bingo.