The coupler is strictly for energy transmission, not for direct heating. High voltage will solve the issue.
It will not in my estimation.
Let's say we want at least 60W of heat on the steering wheel, basically what a 60W light bulb outputs but distributed over the whole steering wheels surface through a wrap of high-resistance nichrome wire. This requires insulating the steering wheel from the heat, and the wire from you, so it's not easy or free but it's certainly doable.
An inductive coupler suffers from high inefficiency, so it's good for charging low-power waterproof devices like a cell phone or toothbrush, but not a steering wheel. It'll be hard to fit one to the steering wheel, so we'll probably need use of a lathe and other fabrication equipment as the transmission side has to be mounted to the dash and the receiving side to the steering column, so we're in for $200 labor/materials in mounting. The alignment and distance between coils is essential, plus we need to keep mud/dirt/branches/whatever from impacting the setup, so this isn't a cheap date.
Phone inductive charging is between 60-75% efficient, father spaced devices (toothbrushes) 50-70%, since we don't have design labs we'll probably hit half of that so 25% efficiency.
60W / 0.25 = 240 W (needed from the tractor)
240 W / 12 V = 20 A (needed from the tractor)
20 amps off the tractor alternator...hope we don't need to run any lights! Doable, but we're likely at the limit of what a tractor alternator can spare.
Looking on
eBay there's a 12V 3A system for $70, if we add a 12V to 24V booster we can get a
100W system for $30 on Alibaba (so figure that's 25W constant power). So we'll have to stack a few systems, figuring about 25W each we'll need 60W / 25W = 2.4 rounded = 3. We might be able to fit 3 sets of coils (6 coils total) in, but the steering wheel will need to be extended so there's not harmonic interference. Hmmm....that's a safety issue.
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So I guess inductive coupling is possible, but if you count labor along with materials that's gotta be north of $500 to get it working, likely $1,000.
I'm using an SAE plug and glove liners, so
about $100 for 12V glove liners (
mine were $35, but that was years ago), and a
single-zone controller is $50. With the rest of the wiring it's under $200, say $300 if you count your labor.
I run two dual-zone controllers for pants/vest, gloves/glove liners (as the suit is used in fall on the motorcycle, but when the snow falls the suit also works for the tractor). If we add that up:
Heated Gloves: $180
Glove Liners: $100
Dual-Zone Temp Controller: $70 x2
High-end Jacket Liner: $280
Heated Pants: $250
I figured for an additional $50 it's better to get heated pants than a heated pant liner.
Coax Female to SAE Cable: $12
12V Splitter Cord: $20
And you'll have to wire the gloves/liners through your sleeves--on that, instead of what I'm doing (which is for motorcycling) I think it would be smarter to use a Y-splitter at the glove/liner connected to single cable and single controller instead of dual-zone controller:
- Heated Gloves
- Heated Liners
12V Splitter Cord: $20 x2
12V 2 Foot Extension Cord: $12 x2
Single-zone controller: $50
If you wanted boot liners you could go back to the dual controller, but like I said previously I buy bigger boots and put wool socks on, but you get the picture.
The heated gloves
and glove liners is redundant, but you wouldn't have cold hands....
So anyway, you'd have to configure what you wanted, but a rough estimate is:
Hands: $180 + $100 + $20 x2 + $12 x2 + $50 = $400
Chest & Legs: $280 + $250 + $70 = $600
Wiring: $35
So also about $1000 and it works by simple SAE plug, and it's more than just the steering wheel, and it''s all off-the-shelf stuff you can buy right now.
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For me the design part is fun, and I was curious what the costs involved would be.
OH! The current draw for the Gerbing setup should be around 9A maximum, likely around 5A under normal use on a cold day.
I buy Gerbing because the quality is excellent, the power draw reasonable, and they have been around a long time as a reliable source. I saw cheaper stuff on eBay and Amazon, but not by much, so I stick with Gerbing.
(I have no connection to any vendor and get nothing from this or any other post.)