Boondocking using HEATING PAD

Mexi
what you say is true..
notice i said call it 8amps battery load not 5.6
and 6 hrs load/sleep cycle, not 12 hrs

96w per hr, for 6 hrs

What I was referring to is "Is's and "Ought To Be's"

When my Trace is on search mode, it takes .045 ampere. The instant it turns "On" that .045 ampere increases to 2 amperes. A 70 watt load doesn't suck 70 watts from the batteries, no, the inverter is not 90% efficient at that load. It is more like 80% efficient. So a true 70 watt load needs 20% added to it 84 watts plus 2 amps (call it 25 watts) to make the inverter more happy. Ah heck, call it 110 watts total. Twelve hours of heating pad at 110 watts is nothing to sneeze at.

i never have a 10 watt load
even turning on the kitchen CFL ligts is 18w
the main load for the go power is the laptop with external drives
of course the TV and DVD are on the same power strip and in standby mode, i never have tested it with a 10watt incandescent resistive load

our trip-lite PV1250 has adjustable load sense and only power the fridge and also draws less than 1 amp, on standby, 2 amps no loss idle if I turn off the loss sense , even the fridge light bulb will not turn it on
when we open the door the light blinks on and off unless the fridge compressor is running

I think PT & BFL have done extensive go power load testing

MEXICOWANDERER wrote:
WAIT! Let me explain my "error"! I forgot! Some inverters have a SEARCH MODE. BUT BUT BUT, load your inverter with a 70 watt load. You are saying your inverter has a greater than 90% efficiency with a 70 watt load?

OK I'll bite...

70 watts at 12.5 volts is 5.6 amperes

The moment your inverter goes off of SEARCH MODE and into power mode, say with a 10 watt load, what is the battery DC burden then?

At 70 watts A.C. load what is the exact D.C. burden on the batteries. As measured with an accurate ammeter?

You don't have real deep cycle batteries.

2 charged #24 batteries would be enough to run your blanket through a night: IF you get a small true sine wave inverter in the 150 watt range.

The 70 watt blanket would at most use about 60 AH which your batteries would easily be able to supply.

You need to do a lot more research on what you need. One night's not a problem, its what you plan to do in a longer term. A 1000 watt gen would be enough to recharge daily, but the batteries you have are not correct for this type of service. If you only plan to do this a dozen times a year, you're OK, if you plan to do often, you need to do a full assessment of your power needs.

Regards,
Doug

I've always been of the (fairly strong) opinion that in most cases if I can find something for the RV that runs off of 12V directly instead of going thru an inverter, I'm better off. If the 12V electric blanket will do the job, it's prob'ly your best option. Maybe do a little research on truckers' forums before buying.

Jim, "Democracy: your vote counts. Feudalism: your Count votes."

MEX - I was holding the 120VAC Electric Blanket plug in my hand one time and was fix en to plug it into the MSW Inverter I had then. The electric blanket controller died of fright before I plugged it in and started pushing out blue smoke... hehe I guess it knew what was going to happen...

Roy Ken

Wizard - We are saying the same thing - just your way of saying it makes better sense...

25AMPs x 2.9hours = 72.5AHs Thats pretty close to the 85AHs rating for the battery mentioned... This much current drain however would drop the 85AH battery to 0% state of charge which you don't want to do.. Adding up all the current drains times the hours of use is really a better way to look at it...

If the total amps added up to 25AMPS then it would only be 2.9 hours of use before dropping the battery to 0% state of charge...

since I measure my actual current draw at my Battery Monitor Panel in AMPS all the time its easy for me to see how much current is being drawn...

just saying...
Roy Ken

I have seen advertised in truck stops a dc plug in electric blanket... says good all night with out draining battery. for $40. look on ebay .
sleeping you only need just a little heat to keep warm. you never wanna run your batteries dead.
once i used the propane heat and ran out of power... by morning not enough juice to start generator... had to start main engine and then start genny.
could have been a real problem if dident have separate start batteries.
propane furnact takes lots of power over night...

WAIT! Let me explain my "error"! I forgot! Some inverters have a SEARCH MODE. BUT BUT BUT, load your inverter with a 70 watt load. You are saying your inverter has a greater than 90% efficiency with a 70 watt load?

OK I'll bite...

70 watts at 12.5 volts is 5.6 amperes

The moment your inverter goes off of SEARCH MODE and into power mode, say with a 10 watt load, what is the battery DC burden then?

At 70 watts A.C. load what is the exact D.C. burden on the batteries. As measured with an accurate ammeter?

We use a go power 300w pure sine wave to power a heat pad
IIRC Idle no load power for the GP is 0.600 amps yes 600 milliamps

Any way 25 amps ...has NOTHING to do with it
5~6 amps plus 10% inverter conversion loss, figure 8 amps load at max heat for whatever hours you use it. 6 hours at 8 amps = 48 amp hrs or about 30% of your bank
To stay above 50% discharge, you will need to recharge your batteries everyday

If your heat pad is old and has the manual three position selector resistive style switch, you can use a MSW inverter if it's new with digital control then you need PSW inverter