Inverter option

[tyler]

Opportunity driven hack: feedback requested.

APC uninterruptible power supply (UPS) Model BEC350R just started acting like battery not holding (alarm with no significant load added). Been hooked
to my home desktop for a few years...

What if... I hook a 35 amp hour sealed wheelchair 12 volt battery I have in the garage to it for use as a 110 power supply while boondocking? Since
these things are designed for electronics, do they have the pure sine wave that the expensive, small, quiet generators produce? The stock APC battery
is 3 amp hour rated. Build a little box to hold and carry it as a unit, and I have a self contained, mobile AC unit with built in charger. By my math
I could charge a little over a zillion phones - ha!
--
1975 Glenbrook
Raleigh, NC

 

[terry1]

I have several UPS's hooked up to LEAD/ACID automotive batteries and they will provide power for much longer than the small LEAD/ACID batteries that
come with them. They DO NOT provide pure sine wave power, it is just a chopper wave and sensitive devices like an induction cooktop will not run on
them. I tried 3 different brands. The computers and TVs have their own power supplies that will accept the chopper or square wave output and work just
fine on them. Remember to use the same format of battery construction that was originally in the UPS, which for all of mine was LEAD/ACID. I have been
using automotive batteries that still have 6 functioning cells for the proper 12.6 volt resting voltage, but not enough current capacity to start an
engine. They will last another year or 2 hooked up to the UPS. I am using one of them as a trickle/maintenance charger on several different batteries.
DO NOT leave the original UPS battery installed, it must be removed from the circuit and the large battery takes its place. I used one in the GMC to
maintain the house battery for 4 years with no problems except that the UPS does not provide enough charge current to run many 12 volt devices without
draining the battery (like the Norcold fridge), or incandescent light bulbs. A couple of LED substitute bulbs is all it takes to eat up the charge
current of the UPS. The charge current might support a 12V>USB phone charger,YMMV. The 110V output will probably power the phone charger for days if
the automotive battery still has some good plate area left in it and is not completely sulfated.
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.

 

[RF_Burns]

Be very careful with using external batteries on UPS units designed for internal batteries. Many are designed for least cost and have no isolation
between the battery and the main power lines. There may only be ~13 volts across the battery, but the from the battery terminals there could be live
120 volts from the power line. In which case touching the battery terminal may be the end of you!

Just saying....
--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
Hubler 1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that

 

[Matt Colie]

Tyler,

None that I have seen are pure sine. Some barely qualify as modified square.

I do have a modified square in the coach to run the reefer and what ever else. It powers electronics without any issue. But, then, so do the two UPS
in the house that keep the house communications alive when the lights go out. I have one UPS for primary communication (telephone and housenet) that
is just that, a UPS of capable rating, but sitting on top of a 60Ahr AGM. I should do Bruce's check. I never thought of that possibility.

Matt

--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit

 

[thomas phipps]

Bonus on using UPS, surge protection. Go for it. Small motorcycle sized batteries would also work in this format. I have UPSs installed on all
electronics that I do not wish to replace after a lightening storm. Alabama is within the lightening strike belt of the U.S.
Tom, MS II
--
1975 GMC Avion
KA4CSG