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Rod Speed Rod Speed is offline
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Default How much electricity do these things use when not in use?

micky wrote

I'd appreciate it any replies went to all three groups that this is
posted to so I don't have to read all three to see all the replies.
When I started in Usenet, that was considered the proper way.

How much electricity do these things use when not in use?

1) Laptop power supplies, when the laptop is not on?

What the battery needs charging wise.

Is it different when the laptop is disconnected?

Yes, very little power is taken with a modern
very small switching power supply/charger.

2) Automobile Quick Charge 3.0 ports?
My car is old so I have to add one, like this one,

Same as the laptop.

Some come with a switch in them and some don't. I picked
this one 'cause it has a 1.1" hole saw, not for the switch. I
suppose some new cars come with QC 3.0 installed?

3) Radios, that have an on/off switch but the switch is
not in the 110v. line. It's somewhere in the transistor
circuitry, after the radio's power supply?

It doesn't actually switch anything, it tells the radio to turn off.

How much power it takes when off varys with the design.

Why don't they put the switch on the 110 volts?

Because the other switch is cheaper.

4) Same question about TV's but since
they are bigger, do they waste even more?

Yep, the worst designs can be quite bad.

If they have to use a relay, they could use a relay. (Yes, I agree
that the remote control receiver has to be on all the time, but
I don't consider that a waste. It could be the only part that is on.)

Yes with the best designs. But some of the smart ones
allow the firmware to be remotely updated so that
still needs to be active to know when to do that.

5) What have I left out?

Everything appliance wise except the most primitive now.

Especially something that is different in nature from the previous 4.

You can get power meters very cheaply.

WRT 1, I've noticed that the black box that's part of the charging
cable is not hot, not even warm afaict, when I'm not charging
anything. Does that imply I'm not using much current?


That I'm using no current?

Nope, its never literally zero.

WRT 2, cars, doesn't the alternator put out loads of extra
electricity anyhow except that there is a regulator to stop that.

There always is a regulator.

If the charger I'm asking about or the lights or any
accesorry (even maybe the heater fan) is using
electricity, does it make the engine work harder?

Yep. But it isnt a fan heater in car.

Is the amount significant?


How many gallons an hour do all the accesories together use?

Bugger all.

Is the amount the engine would have to work to power
a charger that's not charging anything even measurable
with other than a galvanometer**?

It is measurable with a power meter.

** wikip doesn't say this but I was led to believe a galvanometer
is an ammeter for very small currents. Was that true?


Is it still?

Nope, we do it electronically now.

Anyhow, that's what I mean in the previous paragraph.