Stupid, basic, plug question

Probably uses a drop of phantom power like a cell phone charger, etc

 

I can't believe it draws power when not actually charging. It is made to shut OFF. I mean really OFF. It is not like a computer or TV that has power drain even when shut off.

 

yes, it's okay to unplug it, it was designed to be used portably. i plug and unplug mine every night at work. also, there is a lite on the brick so it's drawing a very small amount of power. nothing wrong with kids like that, you've done a great job with them. you might want to walk around the house with them and see what else is on even tho it's off. how many unnecessary digital clocks? cable box lites, t.v. lite, etc.

 

Wow, dude, you really need to get yourself a Kill-A-Watt and plug in some of your household devices, you might be surprised!

 

I purchased a heavy duty power strip with an on/off switch.

 

The power supply draws 2 watts max, when not plugged in, just to light the little LED light on the CCID. If it were plugged in for 41 straight days, it would draw 1 kwh of power, which costs somewhere between $0.15 and $0.32 depending on your electric provider and tier.

 

It draws power, but certainly not enough to make it worth unplugging. There is a lot of lower-hanging fruit in your home, especially if you have a Sony PS/3. Those things draw 100's of watts if they're left powered on. DVR's are also huge power hogs, unused PC's, lights left on unnecessarily, incandescent light bulbs... those are pretty big power hogs.

 

Cable company DVRs may indeed be power hogs, but the current TiVo models pull around 25w, per my Kill-A-Watt. That's 18kwh/month.

 

The plug draws about 1.3 to 1.4 watts when left plugged in. (I measured this several times over 12-24 hours with two different watt meters last week). When the car gets plugged in it spikes for a few seconds up to 2 or 2.5 watts while it determines the charging rate, checks for the timer, etc. If the timer is set it drops back to ~1.4 watts, while waiting for the car to request to be charged. When it is charging it draws about 1350 - 1400 watts from a 110-120v source...till the last ~15 minutes when it drops in ~half.

If you leave the cable plugged in all the time and charge for about 2.5 hours every day you'll be using about 2900-3000 watt-hrs to charge and wasting about 30 watt-hrs to power the cable when you don't need to...or about 1%.

Mike

 

I don't know the engineering, but if I really wanted to cut the power I would consider some kind of switch that is made for repeated action rather that constantly plugging and unplugging the cord. I have extension cords that after six months of repeated plugging and unplugging begin to wear and break down. The part that plugs into your car is made for continual plugging and unplugging. The part that plugs into the power source looks pretty standard (relatively wear prone). Again this is total speculation but I have had numbers of cords go bad at the plug. This is an expensive part !!

 

All this talk about wattage got me Googling, I found this about Kill A Watt:

Kill-A-Watt power meter accuracy - AnandTech Forums

 

Yes, I suspected that. That's why I measured over a long time, and used two different meters (a KAW and a WattsUp Pro). Do I fully trust the numbers I got? No. Could be off by 10% or even 25%, IMO because it is measuring at the low end of the scale, especially for the KAW.

Also, it is important to note that the large errors reported in that link are due to loads that have a high inductive component. (for those that understand...this means a power much lower than 1.0...such as .6 or .7) This is mostly true for motors. But is also true for transformers in electronics.

Like I said in a earlier post elsewhere last week...my PG&E smart meter was 30-60 (?) watts higher than the KAW when charging my car at arounf 1350 watts. Off by 60 is almost a 5% error.

Mike

 

Mike, have you seen my thread on Data Logging? Yesterday I checked my Voltage accuracy on my data logger ( was at 117.0 volts, as measured by my Battery Back Up 123 volts, as measured by my Fluke 122.0 volts) Recalibrated my data logger to 122.0 volts, next time I charge my PIP I'll test it out. I have no way to quantify the amperage on the Kill A Watt or data logger tho.

Attention Kill A Watt Nerds | PriusChat

 

If you believe the outlet plug is bad on the Evse, you can replace it. It's only a 3-wire plug.
I already replaced mine with a right-angle plug. No Problem.

 

Still think a simple in-line switch beats yanking the plug in and out daily if one is that obsessed about the tiny cost of leaving it plugged in.

 

Some of us wiped out those power hogs long ago, and have since gone after unnecessary loads at the 1W level. Individually, phantom loads of that level cost little. But collectively, their combined load has exploded in modern households.

 

That's well under half the average for a DVR -- pretty good!

 

When I installed the Outlet in the garage for the PIP, I also installed a Switch and wired the power thru the Switch to the Outlet. With the Kill A Watt in the Outlet and the cable plugged into the Kill A Watt, I just cycle the Switch to reset the Kill A Watt. Or I can just turn the Switch off when not needed.