I am looking for a way to power a laptop and or printer in my vehicle.
The most effective way would seem to be a UPS plugged into a small inverter to keep it charged while I am out and about. It would probably rarely get more than a few minutes to print an invoice.
I am curious if anyone has experience with this sort of thing and has any relevant insight on UPS battery life under this type of load.
Instead of using a UPS to power the printer, you might look at something like a Canon BJC-85, a bubble-jet printer that has an optional battery. According to the Canon website you can print up to 200 pages per charge.
Actually, it looks like that printer is discontinued, but the HP Deskjet 460c Mobile Printer is still available. The HP website said that it can print up to 450 pages per charge and they also sell an auto/airline adapter.
For clarification:
Are you talking about a printer to print United Parcel Service adhesive labels? If so, this is a thermal printer. If not, disregard.
I think he meant a printer plugged into a UPS, or an Uninterruptible Power Supply
I’d go with a battery-powered printer myself; lugging around a laptop + printer + UPS seems fairly unweildy. The cheapest solution would be to ditch the UPS and print from the car.
If you pick a small bubble-jet (and not a laser printer), then the power requirements would be quite small. Even the lowest-power UPS will keep a low-end PC and monitor going for a few minutes; a printer should last hours. If you really want to go that route, I recall seeing some sort of backpack rig in an APC magazine.
A UPS isn’t something I’d be lugging around myself. One thing I’d make damn sure of is that it wouldn’t beep every 5 seconds w/o power, or I’d go mental.
What printer do you plan to use, and how much power does it consume? Are you sure the inverter by itself is not enough to power the printer?
I’d second running it straight off the inverter. Just consider whether you’d need to go for a true sinewave model or the cheaper modified square wave types. The power supply in your printer is most likely to be a switch mode type and some don’t handle the square wave inverters too good. You won’t need a big inverter, 150W ought to be enough, but check the ratings, allowing for surge currents at switch on and any other load you might have connected too, like the laptop’s charger.
My inverter run time isn’t long though as it’s switch off voltage is 11.5 volt, I guess so I can still start my ute 
But it means I can only charge a couple of drill batteries before needing to run the engine to top the ute battery off. I call it my break time 
This would be a semi permanent vehicle mount. The laptop side was mostly for emergency charging and such. I was thinking UPS rather than direct power from an inverter so I could not accidentally lose what I am doing if I shut off the truck. I had not really considered battery powered printers because I wanted a copy/scan ability as well, and would probably be carrying a small inkjet all in one like a brother 210C or something similar. I am trying to go pretty much total mobile office with the capacity to print invoices and written estimates on site I would also like to be able to scan receipts and such for my various purchases and expenses to minimize the clutter without fear of loss. Space is a minimal issue since its a honda ridgeline. My biggest curiosity is how much run time a laptop pluged into AC via UPS might get since laptops are designed to draw much lower amounts of power. I’m sure that the printer would be a minimal draw in the grand scheme of things since its like 1-2 min bursts of work.
I agree on the beep thing, IIRC there are ways to shut that off on some models, if not I have a screwdriver and some wire cutters to go looking for a speaker.
In these cases I would avoid being tied to a proprietary battery pack by going UPS as well. I am always paranoid about not being able to get parts for stuff.
You’d just be tied to the UPS’s proprietary battery pack instead. 
Seriously, I’d recommend just using an inverter. You can wire it directly to your car battery (with a fuse!) if the power plug is tied to the ignition.
A UPS is really just an inverter/charger hooked to a 12V battery anyway - when one of mine died I replaced the original battery with a car battery.
I agree about the inverter. I just checked CDW, and you can get a 12V inverter that can output 150W for about fifty bucks. That should be enough for a notebook system and an inkjet-based multifunction printer.
Good point about not wanting everything to die when starting or switching off. :smack:
If you don’t want to get tied into proprietary gear, you can make your own UPS.
You’ll need a slave or house battery and a dual battery isolater (dis/connects the slave to the charging system when the vehicle voltage gets to about 13V). Connect the inverter to the slave battery and you’re set, with no worry about draining your starter battery. Any off-road vehicle or marine place should have isolaters. The difficult bit though is finding a safe place to mount a second battery.
But think about what I posted up-thread about sine wave and modified square wave inverters. My laptop charger seems to run a bit hotter connected to my modified square wave inverter, and my DeWalt charger buzzes quite loudly too. It maybe worth while springing the extra for a true sine wave model. Also there are replacement chargers for laptops that run off 12V.
Well, your laptop isn’t going to care if the power drops, and so long as you don’t start/stop while printing, I don’t see a problem.
I use my inverter to recharge my phone, and it’ll stay on for quite a while if I leave it… probably all night. I’d be a bit worried about draining the battery overnight if I forgot anything that required more juice.
This is exactly what I have been looking for but did not know what it was called. I have an inverter already but was wondering about the best way to power it without tapping off the main battery but still being able to charge an secondary battery off the alternator. A second battery is no biggie, I can bolt down a small weather box in the bed for it. Just need to run cabling and drill a few holes.
Of course, in your part of the world it may be called something different, my auto sparky mate here also talks about voltage contolled relays, which are the same thing AFAIK. A place that should have them will be RV type places. One quick and dirty setup I did used an oil pressure switch that “makes” when the engine is running that operated a high capacity relay that connected the battery to the charging system.
Also, use a battery of the same style as your main battery (it doesn’t have to be the same amp/hr). Gel cells, for instance, usually require different charge end voltages than liquid lead acid batteries.