Is it safe to connect a 40W elecric blanket to my ebike battery?
- Thread starter guerney
- Start date
Especially considering their price, battery powered heated socks seem rather too small and puny in terms of energy used and heat output, and so far the feedback from Amazon doesn't inspire as much confidence as the 12V 50-ishW blankets do.
Why were you livingin a ruin? Was it a trendy squat commune and was everyone taking LSD 24/7? Rockwool has excellent sound insuulation qualities if so. I really like the idea of lining the sides of my shed with rockwool, but fear the shed will rot before I get more than a couple more years of use. Applied anti-rot stuff, but I may start adding oodles of oil to the wood as soon as the weather dries a bit. I also need to look very carefully at the guttering.
I'm thinking of using these to connect various things like extra LED rear trailer lights and electric blanket to my ebike battery, as required:
Would waterproof Andersons be better for this purpose, and would they be waterproof enough?
Ultimately I can cover any connector with lots of self-amalgamating rubber tape, but would prefer connectors which are very waterproof at the outset, otherwise I would be forever applying and removing hard to remove self-amalgamating rubber tape.
These are another option:
Would waterproof Andersons be better for this purpose, and would they be waterproof enough?
Ultimately I can cover any connector with lots of self-amalgamating rubber tape, but would prefer connectors which are very waterproof at the outset, otherwise I would be forever applying and removing hard to remove self-amalgamating rubber tape.
These are another option:
Now is the moment to live your dreams! But avoid getting shot!I've always wanted to try one of these:
Särmä TST Thermal Cloak
This multi-functional thermal cloak can be used as a cloak, sleeping bag and emergency shelter even in extreme weather. Fast international delivery!www.varusteleka.com
I also really like their SAS four season sleeping bags with reflective layer, just wish they weren't used and some insane price new.
Sorry ..it just doesn't work that way!. The power of electrical current is the voltage SQUARED divided by the resistance of the load ... Now using 220 V ..which is mains voltage n..and which that blanket works out that the 70 watts has a resistance of 700 ohms. . Now replace the mains voltage with 40 volts of the battery, and you end up with a puny 2 watts of heating!. What you need is something with a resistance of 50 ohms... And then if you put the battery accross it you will get your heating. .. so very thin copper wire .. I would suggest taking the primary winding off a defunct transformer ..and just using it. The wire used in a wallwart for example .. the problem is that it is rather delicate and thin. The wire used by those heated gloves etc will use an Iron wire and nickel which is much higher in resistivity and so can be thicker.For cold days at my remote garden, I'm wondering if it's safe to connect this 40W electric blanket (they've changed the listing to king sized and 70W, but I bought a single):
Carmen C81153 Heated Under Blanket Single Size - White for sale online | eBay
Find many great new & used options and get the best deals for Carmen C81153 Heated Under Blanket Single Size - White at the best online prices at eBay! Free delivery for many products!www.ebay.co.uk
...to my 36V ebike battery? Would the battery explode or be damaged?
The amount of heat needed to keep a body warm is not a lot ... So supplemental heating of 50 to 70 watts with a small amount of insulation beyond that will keep one toasty. Us humans are not really powerful machines... Averaged over a working shift of 8 hours our power output is less that 100watts!. Although sprinting up the stairs, we might produce 2000watts for a few seconds our heat loss is about 100watts average,..a lot of it in the moist air expelled from our lungs . So getting 50 watts of supplementary heat is really a lot.
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I remember being able to do this, but when I tried a couple of weeks ago my right knee gave way before my heart had a chance to throw a fit and produce zero watts.
Thank you @Danidl , yes you're absolutely right on both counts: I should have consulted a textbook and really my only sensible option is to construct a sitting sarcophagus shape using papier-mâché with wire coiled within it's structure of 50 ohms resistance, to sit inside. It should have a hinge for easy opening and closing, be covered with a shiny mylar layer, and have small cut outs for my eyes and mouth for ventilation. For sunny but cold days, it should have clips for sunglasses. I shouldn't need to sit inside it for long - at 50W I would certainly warm up quite quickly. The GuerneyWarmerator™ For Cold Gardeners is invented. Quite seriously, a cycling suit containing robust wire of the right resistance surely shouldn't be too difficult to make? Plug back in, whenever I feel a chill gardening? My battery is capable of of 25amps, and my bike is only using 15A - it could keep me warm while cycling. Or a smaller rigid construction to warm just my calf muscles, feet and back while sitting in a garden chair, and covered with a duvet and space blanket?
Could I use this via a 36V to 12V converter connected to my ebike battery? Weight wouldn't be a problem, it can be kept in the remote garden shed. Do such cheap "Modified sinewave" inverters cause problems for some appliances? This costs only a couple pounds more than a new 12V electric blanket - with an inverter, I could use one of the 40W electric blankets I already use at home:
Car Van Power Inverter DC 12V to AC 220V Sine Wave Dual 2 USB Converter | eBay
Find many great new & used options and get the best deals for Car Van Power Inverter DC 12V to AC 220V Sine Wave Dual 2 USB Converter at the best online prices at eBay! Free delivery for many products.
www.ebay.co.uk
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Those modified sinecwave convertors would be fine .. I didn't want to complicate my previous post by including the fact that the standard electric blankets need AC because the thermostat in them will be using Thyristors If I were doing this I would be tempted to just use a knackered car battery .,if the heater were static.I remember being able to do this, but when I tried a couple of weeks ago my right knee gave way before my heart had a chance to throw a fit and produce zero watts.
Thank you @Danidl , yes you're absolutely right on both counts: I should have consulted a textbook and really my only sensible option is to construct a sitting sarcophagus shape using papier-mâché with wire coiled within it's structure of 50 ohms resistance, to sit inside. It should have a hinge for easy opening and closing, be covered with a shiny mylar layer, and have small cut outs for my eyes and mouth for ventilation. For sunny but cold days, it should have clips for sunglasses. I shouldn't need to sit inside it for long - at 50W I would certainly warm up quite quickly. The GuerneyWamerator™ For Cold Gardeners is invented. Quite seriously, a cycling suit containing robust wire of the right resistance surely shouldn't be too difficult to make? Plug back in, whenever I feel a chill gardening? My battery is capable of of 25amps, and my bike is only using 15A - it could keep me warm while cycling. Or a smaller rigid construction to warm just my calf muscles, feet and back while sitting in a garden chair, and covered with a duvet and space blanket?
Could I use this via a 36V to 12V converter connected to my ebike battery? Weight wouldn't be a problem, it can be kept in the remote garden shed. Do such cheap "Modified sinewave" inverters cause problems for some appliances? This costs only a couple pounds more than a new 12V electric blanket - with an inverter, I could use one of the 40W electric blankets I already use at home:
Car Van Power Inverter DC 12V to AC 220V Sine Wave Dual 2 USB Converter | eBay
Find many great new & used options and get the best deals for Car Van Power Inverter DC 12V to AC 220V Sine Wave Dual 2 USB Converter at the best online prices at eBay! Free delivery for many products.www.ebay.co.uk
The AC question was one I was curious about actually, and again thank you for another informative post. I had assumed everything was operating on DC, after conversion.
After some experimentation at home in a very cold unheated room, I have decided that the following configuration would work better for the garden: a sarcophagus style sleeping bag containing an electric blanket lengthways, with thermostat poking out of a lower aperture afforded by the double zip - this electric blanket resting over my legs warms them very well. A second electric blanket on the garden chair to sit on and warm my back, would also help, plus a space blanket on top: Less than 10A in total.
At home, adding a space blanket on a chair/sofa/bed before throwing on an electric blanket to sit on, increases warmth; works similarly to sticking foil behind radiators. There is the increased fire risk issue to consider, because mylar is very flammable...
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That's a good idea! An old car battery could trickle charge via a solar panel on the shed roof - if I find that battery is flat, I could use the ebike battery.
I would, and light a fire for general warmth, but the ex-GP who owns the gardens I hire doesn't allow us to light fires.
Blimey I can feel little twinges as blood vessels in my legs expand, inside this enclosed sarcaphagus sleeping bag containing a lengthways electric blanket, covered by a space blanket. It feels great!
I'm actually sweating. But I bet it's lowering my sperm count. I've just now turned down the central heating a bit more. I'd love this in my winter garden...
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Here's my Fiido D11 36v 417Wh seat-post battery powering my inverter. So it goes battery to Buck (silver box) then to the inverter; that's giving me 3 x 12v outlets, 6 x USB, and one 240v mains socket. The issue for you here would be the £10 120w Buck I chose limiting current (i.e. it's the same as you get from a car socket). It's plenty for a 12v blanket (I've run a 50w Peltier cool-box from it for 7+ hrs), but Nealh's 300w buck would be better if you're using a mains blanket (I wish I'd foreseen that as a possibility).
Both my 300w true sine and 400w modified inverters work (Bestek, Amazon £40ish?).
That's impressive utility connected to your Fiido battery! Thanks for bringing that inverter to my attention - I had no idea pure sine wave inverters could be bought for so little: £49 now, and unusually it's cheaper on Amazon than ebay:
I've had to exit my GuerneyWarmerator™/sleeping bag and electric blanket combo, because I'm sweating despite the room thermometer showing 13 degrees centigrade (sweaty but cold brow, odd sensation). The issue is now cold face... usually a KN95 Covid mask helps keep one's face warm, so I'll add that next, and turn the central heating down a bit more...
The sleeping bag I'm using, is a £20 cheapo:
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you not got a fire place ?
back when we lived in a damp $hit hole we used these and got them refilled local but nowhere does this round here anymore.
back when we lived in a damp $hit hole we used these and got them refilled local but nowhere does this round here anymore.
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Sadly not, but this solution costs me 1.97p per hour to keep my body warm to the point of sweating (plus standing charge), and that fact is making me quite cheerful. No need to gather wood...
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The GuerneyWarmerator™ is better at keeping my body warm than that, for cheaper. Seriously, you've got to try it, or you will never truly know it's awesomeness. My toes feel great!
Very thorough warming.
The temperature inside the GuerneyWarmerator™ is 31.9 degrees Centigrade
No wonder I was sweating And this is at the bottom of the sleeping bag.
