Powering LCD in the field

[Cal Bickford]

does anyone know of a good way to power a 24" 1920x1200 lcd monitor in the field? Can you use a car battery somehow? What kind of battery life can you expect with the different options? Any input greatly appreciated....

[Boyd Ostroff]

Xantrex makes a variety of portable AC power sources. Check the wattage on your monitor and decide how long you want it to run, then you should be able to pick the model that suits you best: http://www.xantrex.com/web/id/8/type.asp

I just picked up the Xpower 400 myself to have around the house for power outages, it was about $150 at Best Buy: http://www.xantrex.com/web/id/204/p/1/pt/32/product.asp

The data sheet lists typical run times based on the wattage of the load: http://www.xantrex.com/web/id/1372/docserve.asp

[Harold Schreiber]

Hi Cal,

I use a size "27" Deep Cycle RV Battery, along with an inverter, to power up two VCR's and a 5" or 8" LCD monitor for as long as 10 hrs, when I do horse shows in the field.

I run my Cam off a seperate smaller AGM battery.

I've not done the calculations to see just how long I could go.

Check out what Boyd offered.

Harold

[Cal Bickford]

Boyd that looks like it might be just what i'm looking for, you're advice is great as usual! Harold - that sounds intriguing, i wonder how long that setup would power my monitor? Does anyone know of any other brands of portable power sources like the ones boyd mentioned for camparison?

[Boyd Ostroff]

I have another portable power supply made by Husky which I bought at Home Depot. In addition to providing portable AC power, it also will give you 12 volts DC, it has jumper cables for starting your car when the battery is dead, and also a built-in compressor in case you have a flat tire! http://www.homedepot.com/prel80/HDUS...p?pn=100096992

[Cal Bickford]

The lcd I'm using is a 24" benq fp241wz. Can anybody tell me how I can find out how much wattage this thing uses? So i can figure out how long one of the portable power sources will last?

[Cal Bickford]

never mind i figured it out

[Bill Ravens]

most LCD's run off a power supply that provides 9 or 12 volts dc. One of my screens is listed at 12v 7 amps, since w=VxIxPF, that's 84 watts, assuming PF=1. A 12 volt battery with an amp-hr rating of 35 will provide 35 amps for 1 hour or 7 amps for 5 hours.

[John Hotze]

I've been servicing computers for more years than I like to think about and was thinking about various solutions to what your talking about. I decided to go with an 800 watt UPS that I purchased (about $100) from Best Buy over the weekend. I haven't benchmarked it yet but I suspect it could do the job for serveral hours for you. I wanted it to power an 8 channel audio mixer, my camcorder, a small DVD player that I'm using for a portable monitor when I'm taping and a few other small items. Aside from a power cord that will be hanging off of it, I see no reason that this won't be a simple easy solution plus if I wanted to I could use it for what it was intended for at home. I have also used a marine deep cycle battery with an 300 watt inverter in the field before. The inverter was about 1/3rd the size of a brick. I'm just reluctant to haul that heavy battery around unless I setup a portable arangement on a foldup dolly I purchased from Home Depot. I was just looking at a lighter smaller alternative. The 800 watt UPS is only slightly larger than a brick and very manageable to carry for an old man like myself.

jkh

[Boyd Ostroff]

Originally Posted by John Hotze

Aside from a power cord that will be hanging off of it, I see no reason that this won't be a simple easy solution plus if I wanted to I could use it for what it was intended for at home.

Welcome to DVinfo John! Have you actually tried using the UPS for this? I have in the past and found several problems. First, almost all UPS'es have a very annoying beeper that sounds when they run on battery power. Older ones had a switch to disable it, the new ones that I've seen do not. So you may need to open up the unit and disable the beeper somehow.

But a bigger problem I've found is that they are only designed to provide power in a situation where they are already connected to the line during an outage with their power switch on. So if you unplug the UPS and turn it off, it won't power up again when you try to switch it back on unless it's connected to a working AC line. They may not all behave like that, but the cheap one I bought (in the hopes of powering a monitor) was like this and was consequently useless.

Let us know how this works for you, and if it's a good solution give us the make and model number.

[Dan Keaton]

Dear Boyd,

I have a good, sine-wave 1000va UPS which will not power up without AC power, just like yours. This unit is an HP unit. It even has inputs for extra batteries.

I also have a cheap 350va unit with a very small battery, but it will power up without AC power.

I believe that if I have a power loss, I can use the small unit to bootstrap the larger unit. After I boot up the larger unit, I can then shut off the smaller unit.

The smaller unit is an APC Back UPS ES 350.

[Boyd Ostroff]

Originally Posted by Dan Keaton

I believe that if I have a power loss, I can use the small unit to bootstrap the larger unit.

That's very interesting. Heh, but why not just plug the big unit into itself and then it will run continuously and recharge it's own battery like a perpetual motion machine! (JUST KIDDING ;-)

But seriously, UPS'es are obviously not intended for use as portable power supplies so it will be a bit of a kludge using them for that. Next time you're in Best Buy take a look at the Xantrex unit I mentioned above. It seems to be well made and is probably a better fit for this application. At $150 it doesn't cost much more than a UPS and can also be used as one if needed. But it is also intended for stationary applications since it has a cord permanently attached to it and is an awkward shape and size to carry around.

But you might also want to check out the Husky unit at Home Depot. It's cheap, has a removable power cord, and is easier to carry around with a large handle on it.

[Eugene Kim]

Boyd, about how long will a typical portable car jumpstarter power a 15.4" LCD HDTV monitor in the field.

I'm guessing about 6 to 8 hours, but I don't know the typical wattage of one of these LCD monitors. How about a laptop, most draw around 30 watts right? I bought a high-cap, non-oem battery for my laptop/DV Rack combo, but have never been able to get it to power up or charge for some reason, despite a warranty return, such a waste of money. For that money, I could have just bought one of these jump packs. The cheaper ones don't have an AC outlet, but they do have a 12v cigarette lighter plug so it's fine if you've got an inverter like me.

Walmart has one, just checking the other day, that goes for $99 with TWO AC outlets, I mean how great is that! ...doh, that is until I tried lifting it. It's a bohemeth lead anvil I tell you, way too heavy for something you'd want to lug around in the field, and noticeably heavier than the other medium-sized jump pack I've held. The 12v cigarette outlet one that Walmart sold for $69 was way smaller, and quite a manageable weight, however, with a handle as well. It's the smallest jump pack I've seen with an external power source outlet built-in.

This said, the two outlet version (gotta love...or hate, smile...Walmart, they always carry cheap, why didn't I think of that, solutions) I think would be a GREAT solution for those who've got the good fortune of having little minions to carry all your stuff for free. More specifically, think about if you want to use DV Rack with an external hard drive. The BUS powered ones are of a slower speed and don't really come in a high capacity.

With this, you can work on say a several day long project, and not have to offload the recorded files at night. Just buy a 500gb, external hard drive (so cheap these days), plug both it and the laptop in, and you're good to go whether in the field or inside.

Btw, what section do you find the Xantrec power supply unit at Best Buy? I've been to two, and not been able to locate it at all.

Is it an item that only some Best Buy's sell, i.e. a mostly online item?

Thanks.

[Boyd Ostroff]

Hi Eugene. I ran a 22" LCD screen for awhile on that jumpstart battery pack. Maybe 2 hours? It still seemed to have plenty of juice left in it.

I have an APC laptop battery which is a big, flat thing that comes with a cable and a bunch of adaptor plugs to fit a variety of laptops. Is that what you're talking about? Mine is pretty good, will run my Powerbook G4 with everything full up for maybe 3 hours. You can choose the output voltage on the battery, and I found that one of the adaptors fit my Sony 17" LCD screen in place of the power brick. But somehow I lost the adaptors, and then gave the LCD to my daughter, so I never gave it a real workout. But it might also be a possible field monitor power supply. This is the one I have: http://www.compusa.com/products/prod...tebook_Battery

I saw the Xantrex power supply awhile ago on Best Buy's website, but when I looked in a couple stores I didn't see it. In the meantime I forgot all about it until I was looking for a new flatbed scanner at Best Buy and spied one... so I bought it! :-) It was in the computer department with the UPS'es.

[Harold Schreiber]

Hi Cal, and everyone else;

Just an update: Cal, you did not tell us what kind of video you were doing or in what kind of "in the Field", or how long you needed to be powered up. So it's kind of hard to give you specific suggestions.

When I said "in the field" I literally meant it, as some of the horse shows I Video are in fields with no electricity close around.

My most recent show was a 2-day afair on May 12 & 13th, at 9 hrs per day. I now have a Honda EU2000i portable generator. It ran 4 VCR's, 2 Cams, and 2 monitors for less than a gallon of gas per day. It never got off idle. Great set up. Had the big batteries ready as a back-up.

Just another option to consider.

Harold