Electric blanket and inverter

[Sunset_Gypsies]

Found an electric blanket that the inverter does not fry.

SoftHeat by Perfect Fit | Luxury Low-Voltage Electric Heated Blanket

The control and blanket run on 18 volt DC, separate power supply feeds the control from 120 vac. Works fine with voltage from a modified sine wave inverter.

Could probably replace the power supply with a 12 to 18 volt DC to DC converter to save energy.

[Rice]

wanderingbob wrote:
They do make 12 volt blankets , look in truck stop shops .

But they're small--like 5 feet by 3 feet. And they can't be washed because the cord is hard-wired.

I think it's the same for 12-volt mattress pads, too. They're all for using in a bunk in a truck.

I've had the Soft Heat electric blanket mentioned by the OP for probably 8 years or so of fulltime use--on a MSW inverter until we got a PSW inverter a year or so ago. My only beef is that the fabric is kind of "sticky" (microfleece), so it kind of drags on the sheets when you're making the bed.

I have the full size on a queen bed, because I wanted only one controller. It hangs over the sides by about 4 inches, which works fine for us.

[wanderingbob]

They do make 12 volt blankets , look in truck stop shops .

[valhalla360]

wopachop wrote:
My friend is always cold and looked into electric blankets. They can form some type of field that the human body does not like. I dont remember the details besides deciding it's not good to sleep under them.(some of them.....all of them???)

Instead she cranks it full blast for an hour and turns it off before climbing into bed.

Just something to research if you care about that stuff.

I'm not worried about having to wear a tinfoil hat to bed...but fire risks can be real.

We have used them in the past and pre-heating the bed is a great option. Once heated up, your body heat will keep it warm.

[valhalla360]

Sunset Gypsies wrote:

valhalla360 wrote:
Unless I'm misreading, it doesn't need a DC power source. It's 120v AC powered but the heating circuits are DC. Conversion is all internal to the control unit.

Changing the voltage won't change the efficiency. Wattage is what determines heat output. Wattage is Volts x Amps If you crack open the controller and mess with the voltage assuming you don't increase the amps, you do reduce power consumption but you could achieve the same effect by simply turning down the thermostat so it runs for a shorter period of time.

Yes it does work fine as it is. I was referring to power loss in the main inverter (12vdc to 120ac) and the blanket's power supply (120vac to 18vdc). A 12vdc to 18vdc converter replacing the blanket's power supply and running of the 12 volt circuits might be more efficient as it would remove the power loss in the inverter, but probably not enough to justify the cost of the converter.

That makes more sense but as you say, how much power will you really save? Also, I'm betting the control head is not designed to be pulled apart and rewired, so how sturdy will it be an how much cost and effort will be involved.

[Sunset_Gypsies]

wopachop wrote:
My friend is always cold and looked into electric blankets. They can form some type of field that the human body does not like. I dont remember the details besides deciding it's not good to sleep under them.(some of them.....all of them???)

Instead she cranks it full blast for an hour and turns it off before climbing into bed.

Just something to research if you care about that stuff.

Yes you are right. Most electric blankets use AC to heat the blanket which emits EMF. The blanket I referred to uses DC to heat it which reduces the EMF considerably.

[wopachop]

My friend is always cold and looked into electric blankets. They can form some type of field that the human body does not like. I dont remember the details besides deciding it's not good to sleep under them.(some of them.....all of them???)

Instead she cranks it full blast for an hour and turns it off before climbing into bed.

Just something to research if you care about that stuff.

[SidecarFlip]

Lwiddis wrote:
Everything is more safe with a pure sine wave inverter.

+1. Besides a quality PSW isn't all that more expensive.

[theoldwizard1]

At my parents house, the master bedroom was an addition with very poor heat. Not uncommon to drop into the 50s in there during winter.

They said a heated mattress pad and a couple of heavy blankets were more comfortable than an electric blanket.

[Sunset_Gypsies]

valhalla360 wrote:
Unless I'm misreading, it doesn't need a DC power source. It's 120v AC powered but the heating circuits are DC. Conversion is all internal to the control unit.

Changing the voltage won't change the efficiency. Wattage is what determines heat output. Wattage is Volts x Amps If you crack open the controller and mess with the voltage assuming you don't increase the amps, you do reduce power consumption but you could achieve the same effect by simply turning down the thermostat so it runs for a shorter period of time.

Yes it does work fine as it is. I was referring to power loss in the main inverter (12vdc to 120ac) and the blanket's power supply (120vac to 18vdc). A 12vdc to 18vdc converter replacing the blanket's power supply and running of the 12 volt circuits might be more efficient as it would remove the power loss in the inverter, but probably not enough to justify the cost of the converter.

[wa8yxm]

The Controller it appears runs off a DC supply that is MSW friendly

That's the problem when I was a child everythign was thermal breakers basically, MSW, PSW, DC it mattered not.. But today the controls are electronic and MSW tends to fry so this thread is a FIND.

[valhalla360]

Unless I'm misreading, it doesn't need a DC power source. It's 120v AC powered but the heating circuits are DC. Conversion is all internal to the control unit.

Changing the voltage won't change the efficiency. Wattage is what determines heat output. Wattage is Volts x Amps If you crack open the controller and mess with the voltage assuming you don't increase the amps, you do reduce power consumption but you could achieve the same effect by simply turning down the thermostat so it runs for a shorter period of time.

[Lwiddis]

Everything is more safe with a pure sine wave inverter.