is it safe to use Kill A Watt with EVSE ?

Hi,

Is it safe to leave the stock Nissan EVSE attached through a Kill A Watt device while charging???

And can I just leave the EVSE plugged into the Kill A Watt for a week or so with no danger of overheating, or burning out the Kill A Watt device, or even my garage?

I have the Model P3 with max on back listed at at 125V / 15A max power 1875VA

I don't want to burn down my house..

thanks !

The Kill A Watt is not actually designed to handle that level of power continuously and you run the risk of it melting or worse. I wouldn't do it.

timba33 said:

Is it safe to leave the stock Nissan EVSE attached through a Kill A Watt device while charging???

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Thanks. I did a search and noticed some others used a Kill A watt to measure KWH used.

What is the best way to measure total KWH used from the wall, not what goes into the Leaf batteries. Trying to get a handle on a good measurement of the Leaf Charging KWH ..

thanks.

This forum is terrific... So much information.

I use a regular KWH meter like the utility puts on the side of your house. They are readily available on ebay, in both 120V and 240V versions. You can get them for about 30 bucks, and buy the base from home depot or lowes for about the same amount. You need to be somewhat proficient with wiring to make it work. That would be the safest way to monitor your KWH.

A company called TED, The Energy Detective, offers a product that some of us use. Mine is very reliable and informative. You can set up several channels to monitor your total household power use, a solar or other renewable energy system, etc. You can view and save data on a computer and there are apps to view data on mobile devices. It does cost a few hundred dollars and it can be a bit finicky to set up. You need to make some connections inside your power panel. TED used to offer a simpler, single channel system that is perfect for monitoring a single circuit, but I'm not sure whether this is still available.

There are other companies that offer similar systems to TED, and some of them use more modern technology. A search for home energy monitoring systems would be productive.

I would not use the Kill A Watt for constant use.

Here is what mine looked like after I reconnected the prong that separated from the PCB. It had become hot enough that the solder melted. Note the heat deformed plastic. I was charging L1 at 12 Amps, well below the device rating of 15 Amps.

http://www.billj.net/killawatt.jpg

I've been leaving one connected since it's supposed to be able to handle normal L1 circuit loads, but maybe I'll stop doing that now...

You hardly need a meter. You can just look at the percent charge when you plugged it in and subtract from that the charge when you unplugged it. You can calculate the KWH put into the battery from that. If you want to calibrate your charge o meter, just plug into a public level 2 charger with a KWH used display, and accurately observe how many KWH is pushed into the battery for every percent of charge added. This number will change over a long time as your battery loses capacity, but I would imagine it's pretty stable for a couple of months.

I was using a Killawatt in series with an air conditioner that drew 11A. I had to resolder the connections after a while. They are definitely not for heavy current long term use.

LeftieBiker said:

I've been leaving one connected since it's supposed to be able to handle normal L1 circuit loads, but maybe I'll stop doing that now...

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Basd on my experience, I certainly would.

I now use mine to get a quick current or power reading only.

I used a Ryobi version for maybe a week or so. Didn't notice any untoward warmth, but after all L1 is at the top end of what you can demand from a household outlet and the fewer contact interfaces, the better. The device wasn't doing much more for me than satisfying curiosity at that point and so I removed it.

johnrhansen said:

I use a regular KWH meter like the utility puts on the side of your house. They are readily available on ebay, in both 120V and 240V versions. You can get them for about 30 bucks, and buy the base from home depot or lowes for about the same amount. You need to be somewhat proficient with wiring to make it work. That would be the safest way to monitor your KWH.

Click to expand...

I do that too. DaveinOlyWA describes how to install such a meter here:
http://www.mynissanleaf.com/blog.php?u=291&b=92" onclick="window.open(this.href);return false;
I found it a fairly straightforward "Do-It-Youself" (DIY) job, but I am comfortable with doing basic electric wiring.

My setup:

Based on numerous pics posted online, no, it is NOT safe to use a Kill A Watt with an EVSE.

ebill3 said:

I would not use the Kill A Watt for constant use.

Here is what mine looked like after I reconnected the prong that separated from the PCB. It had become hot enough that the solder melted. Note the heat deformed plastic. I was charging L1 at 12 Amps, well below the device rating of 15 Amps.

http://www.billj.net/killawatt.jpg

Click to expand...

I have the same model Kill A Watt and used it repeatedly with my Leaf L1 EVSE. I did not have any damage to it and never noticed any heating. It was used in March/April in NY, so the ambient was fairly low. However, after hearing of the multiple problems I can't recommend anyone leave a Kill A Watt unattended to measure KwH.

like2bike said:

I have the same model Kill A Watt and used it repeatedly with my Leaf L1 EVSE. I did not have any damage to it and never noticed any heating. It was used in March/April in NY, so the ambient was fairly low. However, after hearing of the multiple problems I can't recommend anyone leave a Kill A Watt unattended to measure KwH.

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I think that is a wise recommendation.

Ingineer Phil once reported that QC seems to be a bit shaky - some units are better than others. Perhaps you got a good one, I apparently did not.

Mine measured about 1370 watts. Just do the math. I wouldn't leave if plugged in.