12 Volt Electric Blankets

RoadDawgg

Expert Expediter
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Are these cost effective and sufficient for keeping warm with the engine off? Say down into the teens, above the point where diesel gels up. Or will this kill your battery if you're able to get 8-10 hours of bunk time?

Thanks!
Christopher
 

Zoli

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Are these cost effective and sufficient for keeping warm with the engine off? Say down into the teens, above the point where diesel gels up. Or will this kill your battery if you're able to get 8-10 hours of bunk time?

Thanks!
Christopher

I think that you will drain the batteries with this blanket...And if you use it with your engine running you don't need it....Buy a Honda EU 2000 generator if you want to stay in this business.
 

chefdennis

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Are you running a house bank of batteries with a inverter and battery seperator? I have a hamilton beach heated matteress pad that is 120 v and run it off the inverter. I turn it on and then get in the sleeping bag and all is nice and cozy....

I wouldn't run anything 12 volt all night if you are running it off your starting battery, that battery is not decided for those constant draws and even if it last a while, over time you are going to see the battery last less and less time and one day, you will be jumping it to get it started and then you can bet that you will be jumping it more often....
 

redytrk

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In the directions tell you to only use it to warm the bunk while the engine is running. the bunk will be nice and warm. I think a extreme cold sleeping bag is a better answer.

If you use isolated battery's, you will protect your start battery. Isolators usually shut off at low voltage.
 

rfields200

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I used one of these I bought in a truckstop in Mn. I would use it all night and stayed toasty warm except for my head so I would wear a winter hat while sleeping. They are designed to draw very little juice from your batteries. My truck only had 2 batteries and I never had a problem starting the truck the next morning.
 

Turtle

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Group 31 Truck batteries are the same internally as Marine "deep cycle" batteries. The Marine and truck batteries are dual purpose in that they crank the engine and can handle low amp draws, as with a trolling motor, Espar heater and 12-volt (not 120 volt) electric blankets. So if you have multiple truck batteries, you can get away with using small inverters and some 12-volt appliances like electric blankets.

If you have a single truck battery, or are in a van, forget it. Use a separate, isolated auxiliary or house bank for everything other than starting the engine, and use the cranking battery for nothing other than cranking the engine.

12 volt electric blankets will draw about 4.5 amps. Over 10 hours that's 45 amps drawn from the battery. When it's really cold, batteries have fewer cold cranking amps to begin with. Drawing 45 amps out of a battery which is near zero degrees will reduce the CCA by well over 100 amps. The last thing you want to do is reduce that even further by drawing the battery down just when you need the most CCA you can get.

CCA (Cold Cranking Amps) is a rating for the number of amps a new, fully charged battery can deliver at 0° Fahrenheit for 30 seconds, while maintaining a voltage of at least 7.2 volts, for a 12 volt battery (1.2 volts per cell). The higher the CCA rating, the greater the starting power of the battery.The cranking voltage will start out at 12.8 volts, but will quickly drop to 7.2 volts within 30 seconds, to the point where the battery is depleted.

MCA or CA (Marine Cranking Amps or Cranking Amps) is the same exact rating as the CCA, except MCA and CA is for 32° Fahrenheit.

Cranking Batteries might be rated at 500 to 1200 CCA. Few engines will actually require that many amps to start, and even fewer will require that many amps for a full 30 seconds to start. Some big trucks will, tho, and it's why many of them have several batteries. But with van, a couple hundred amps for a second or two is all that's needed to crank the engine. 200 amps for 2 seconds is about 7 amp hours drawn from the battery, which the alternator's charging system will quickly put back into the cranking battery (takes about 15 minutes on average).

Cranking batteries are designed to provide very high amp draws of for a very short period of time. They cannot handle low amp draws for sustained periods, or high amp draws (microwave) for more than a few seconds.

Hybrid (marine deep cycle) batteries are designed to provide cranking amps and can handle low amp draws for sustained periods. They cannot handle high amp draws for more than a few minutes.

Deep Cycle batteries can provide enough amps to crank an engine, but will provide fewer CCA and MCA than a similarly-sized cranking battery. They can handle both high and low amp draws for sustained periods. Some (gel batteries) can routinely handle very deep discharges (20% DoD) without heading for an early grave, while others (AGM and wet cell) will last considerably longer if discharged only to 50% DoD or less between charges.

So the three basic types of batteries, Cranking, Hybrid and Deep Cycle, are all designed for different purposes. All perform exceedingly well when used for the purpose they are designed for, and all perform badly when used for something they are not designed for.
 

bluejaybee

Veteran Expediter
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I have tried 2 of the China crap 12v blankets. I bought them from 2 different suppliers with different brand names. Both of them gave trouble in the switch. It is supposed to cut off after a couple of hours. Instead of cutting completely off, the switch just got overheated and started smoking. They are not for me!
 

layoutshooter

Veteran Expediter
Retired Expediter
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Watch where the batteries are made as well. Many of those made in China use inferior components. I try to stick with batteries made here.
 

skyraider

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US Navy
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I use a 2200 watt generator,,and sometimes the electric blanket, but mine is 110 v blanket,,but this year Im using propane Mr. Heater,,in a cvan. Each front window is down about 1inch,,and never a problem keeping the van warm, and by warm 65 degrees on low at 30 degress outside,,so I hve not tested it at say minus 20. I do run the generator for the microwave, and sometimes my 1500 watt electric heater,,but I prefer the gas heater,lots warmer and cheaper over the gas generator.
 

Turtle

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The the caveman days before Espar, I used a 12-volt electric blanket. The next winter I got an Espar heater. Now I sleep very comfortably and warm and toasty on top of the covers, usually nekkid but sometimes while wearing socks, no matter how cold it is outside. :D
 

layoutshooter

Veteran Expediter
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The the caveman days before Espar, I used a 12-volt electric blanket. The next winter I got an Espar heater. Now I sleep very comfortably and warm and toasty on top of the covers, usually nekkid but sometimes while wearing socks, no matter how cold it is outside. :D


I could tell you a story about a guy, nekkid, only ONE sock and a trash can full of purple....................., nasty, FUNNY, but nasty.
 

geo

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US Navy
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i tried one of those electric blankets and asked would it drain the battery they said it would not but it did
after i add extra set it worked great
so add extra battery
 

Jefferson3000

Expert Expediter
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I used a 12v blanket that I bought at Love's for quite some time. The only drawback for me was that it was a throw instead of a full size bed blanket. I always shoved it between the lower blanket and another and it kept me toasty and ran at a very low amperage. However, if it was down in the teens, I had something else running, as I am a native Floridian and that's just COLD.

I have an owner op that uses one in conjunction with his sleeping blanket. He loves it.
 
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