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Elektric heated vest

Homemade heated vest

In this picture I hold my electric vest against the sunlight. The heating wire can be seen, running zig-zag through the vest.
heated vest
I had enough material, tools and assistance. But it was still a considerable challenge to make this heated vest.

Because I sometimes don't lie on my bed, and sleep with the vest on, it must be very safe. So my heating vest operates on a low voltage.
I bought a few used electric blankets of the brand Inventum, which have approximately the same transformer. I removed the heating wire from one electric blanket. That turned out to be over 17 meters of heating wire. The complete heating wire is in my vest. It was difficult to place some heating wire in the front side, so now only my back is heated. Due to that, my back becomes easily sweaty. So some days I have to put on dry clothes a couple of times.
The heating wire consists of a few copper wires, each with thin layer of insulation. Each copper wire must make good contact when the heating wires is soldered to another wire.
From the upper heating wire to the lowest heating wire heating wire is 60 cm. This is only for my back, because I don't have a heating part for my neck.
The power is the same amount as the original electric blanket, and is 40 watts.
My homemade electrical heated vest was finished in 2007.
The vest is made of thick cotton, because cotton can withstand a lot of heat.
I wear the vest over an insulated vest, so the heat is more evenly distributed. An over the vest, I wear a coat. The room temperature is by the way 22°C.

As additional security, I have tried to make the connections in the vest water proof, by using heat shrink with glue.
I also have a thermal fuse fitted in the vest, but that is of little use, since it can become hot elsewhere in the vest.
A good plug was not easy to find. The plug must make a good connection (it must be able to carry 2.5 A) and the plug should release, in case I walk away and accidentally forget to disconnect.
First I used plugs like the cigarette connector plugs in a car. But those didn't make a good connection, and became hot.
Now I use Tamiya connectors. The wires easy break close to the connector after some time, but now I have put construction adhesive on it. It looks ugly, but for now it works.
In the car I have an adapter cable to use the cigarette lighter socket of the car.
tamiya plug tamiya plug tamiya plug

Everywhere in the house I have transformers, so that I can connect the heated vest.
transformer
Normally the electric blanket is connected to the transformer with a connector in the transformer. This connection, however, became hot. So some power was lost by that connection. Therefore, I soldered the wires inside, and dropped that connector.

Since my heating vest works on low voltage, it can be used with batteries. A lead-acid battery or rechargeable batteries would become heavy and clumsy, and a Li-ion battery is difficult to use and often expensive.
This Li-ion battery was cheap and it works well:
Li-ion battery
This Li-ion battery is 12 volts 6500 mAh, and weighs only 200 grams. It consists of 3 cells, and a PCB. The PCB is a circuit board to protect against excessive discharge and against shortcut. So the heated vest can be connected directly to the battery, and it will work for almost 3 hours.
I bought this Li-ion battery with charger in 2009 for 22 euros.

For my health my heated vest make a clear difference. Beside a few months in summer, I have approximately 21 hours per day extra heating. An electric blanket when I lie in bed and the heated vest if I am not lying in bed.
A small disadvantage is that my body gets used to it. I don't do well without extra heating.
Another disadvantage is that it is not good for my skin on my back. So I tried the vest on my front, but after a year it turned out to have a bad influence on my stomach. Today I have this jacket on my back, but I try to set it not too high, and in the shower I set the water not too high, and the heated blanket on my bed is set less warm.

If I had to make another heated vest, I would use conductive fabric (without wires) and attach that to an existing vest.
Or I would convert an existing thermal vest. But making a small vest large enough for me, might be difficult.

Since 2010 I don't use this vest indoors anymore.
I have electric heating pads against the backrest on my office chair and living room chair. I do still use my homemade heating vest in a car.

Heated vests

When I was halfway with making my heated vest, I found out that electrical heating jackets exists for motorcyclists and also electric heated vest for back and neck for home usage.

A few years later, about the year 2008, a large number of electrically heated vests came on the market, including many with a battery.

Electric heated vests for use indoor are for example:
    • Inventum heated cushion, type HNK36, 100 Watt, 50 cm long.
    • Medisana heated cushion, type HKN, 60 Watt, 65 cm long.
    • Bosch heated vest, type PFP5030, 60 Watt, 56 cm long.
    • Beurer, type HK56, 100 Watt, 50 cm long.
    • Microlife, type FH300, 56 cm long.
These heated vests are for indoor use and operate on 230 volts, and switch themselves off after one and a half hour.
They are too small for me. For me, a length of 75 cm would be needed.

This is the Inventum HNK36 heated vest:
Inventum heated vest
The Inventum heated vest is 50 cm long, but from the upper heating wire in the neck part to bottom heating wire is 42 cm.

The Inventum heated vest turned out to be useful, so I bought a second one in 2012:
inventum heated vest
On the photo above, the inner part of my old Inventum heated vest is on the left. The new one is on the right.

This is the Medisana Heating cushion for back and neck HKN heating cushion:
Medisana heated cushion
This Medisana heating cushion is 65 cm long. From the upper to the lower heating wire heating wire is 47 cm. There is no heating in the upper 8 cm, so it is mainly the back that is heated. To wear it, a white band is around the neck, tight against my throat.

This is the Inventum HNK55 multi-functional heating pad:
Inventum HNK55 Inventum HNK55 Inventum HNK55
Brand and Type: Inventum HNK55
Price: about 40 euros in 2013
This heating pad can be worn around the waist to heat a part of the back. It can also be folded to be used for the neck.
I use it for my neck, and it is pleasant to use. When I wake up in the morning I sometimes use this heating pad for an hour to make my neck more flexible.

This is the Medisana "Comfort heating pad HKM":
Medisana comfort heating pad
I bought this heated cusion because it would very flexible. But it wasn't very flexible.

This is the Inventum HNB60 heated cushion.
Inventum heated cushion
This heating pad uses a battery.
The HNB60 is 40 cm by 30 cm and can be slid under clothing.
The battery is only a small battery of 9.6 Volt, 2100 mAh (8 NiMH batteries, size AA). Nevertheless, it produces quite some heat, since only one side of the cushion becomes warm. There is probably an insulating and a heat-reflective layer in the cushion.
The battery went broke quickly. The quality of the battery was not good enough to deliver that amount of current.

Heating cushion without brand:
brandless heating cushion
This heating cushion can be placed in a car seat.
Some of these cushions have only a small heating element, but this cushion heats over most of the pillow.
For me this cushion was not convenient, because also the seat is heated, and only a small part of my back is warmed because of my long back. Futhermore, this cushion is not hot enough for me, because it has a thermostat built in.

History

An electrically heated vest was developed as early as in 1932. It was made for the traffic police in the United States. The power was supplied by electric contacts in the street.
It is not known whether these were actually used in real life. The photo does not show clearly how it was made.
A picture of this is in the Dutch archive at www.geheugenvannederland.nl and at www.spaarnestadphoto.nl with photo number SFA022809229.

The Dutch organization "ANWB" (the largest travelers' association in the Netherlands) had their own brand for clothes: "Human Nature". In 2014 they had jacks en gloves that are electrically heated. I think I can say that in 2014 electrically heated clothes are common.

Last change to this page: November 2016