EVSE Monitoring Hardware / Software

[Chris Naps]

*Note: Mods might want to make this a sticky because I couldn't find much information about this topic and it is evidently quite useful.*

Brief Description:
I received a few Tesla HPWC's and I want the ability to monitor their usage.


My goal:

I want to put the chargers on their own breaker. When I do this I want the ability to monitor each station. When I have the option to monitor the stations, I also want the control of remote management - this management will allow me to turn the breaker/chargers on/off at the click of a button.

I want to be able to monitor the KW for that current charge (there is probably not an option for that, but a grid with a 0-24 hour scale would be similar enough.) I also want to monitor the KW for that day/month.


Overview:
The control to remotely turn the HPWC on/off.
The ability to monitor the KW in real time for that charge (if the software provides a 0-24 hr. grid, then that is fine.)
It gives me the ability to see how much I am going to be paying in electricity for that day/week/month/year.
It would be nice if it had an IOS or Android capability. (web based will be fine..)


The products I have found so far:

eGuage
TED
EnergyHub


P.s. It would be best if the installation does not take a the smartest man in the world to install and that it is cost effective.
P.s.s. If you have experience with the set ups that I mentioned please do not hesitate to post your experience with it.

Thank you!

 

[tezco]

You can use the Tesla App to turn charging on and off, or you could use a contactor (relay) in the line to manage power to the EVSE. I like the looks of the eGuage, but my garage is too far away so I built my own (here).

 

[Chris Naps]

You can use the Tesla App to turn charging on and off, or you could use a contactor (relay) in the line to manage power to the EVSE. I like the looks of the eGuage, but my garage is too far away so I built my own (here).

I cannot use the Tesla app if it isn't my vehicle. I will be charging a multitude of vehicles. Unless there is an app that controls the HPWC; if there is, definitely let me know.

You did an awesome job with your set up, but are you able to enable/disable power remotely - via web or app?

Are you also able to remotely tack the software you use over the eeb or phone app?

And what do you mean your garahe is far away so you built your own? Are you familiar with the eGauge software?

Thank you.

 

[simonog]

Personally I would use HomeSeer as controlling software because it allows you to control manually from multiple platforms and to do event processing (if certain conditions are true then perform certain actions)

controlling the the hardware inc the power switching is a different problem

 

[mitch672]

You really don't want to be switching the AC power on/off, a better way is to interrupt the pilot signal via a small remote controlled relay. There are numerous ways to do this inexpensivly.. A raspberry pi with a relay control board attached is very inexpensive, and you can install a web server on the RPI for remote control. Also this would be minimal modification to the HPWC, just adding a SPST relay inline with the pilot wire, have it normally closed, so if the controller fails/is disconnected, the HPWCs still work.

 

[tga]

You really don't want to be switching the AC power on/off, a better way is to interrupt the pilot signal via a small remote controlled relay. There are numerous ways to do this inexpensivly.. A raspberry pi with a relay control board attached is very inexpensive, and you can install a web server on the RPI for remote control. Also this would be minimal modification to the HPWC, just adding a SPST relay inline with the pilot wire, have it normally closed, so if the controller fails/is disconnected, the HPWCs still work.

That's an interesting idea. You could also modify the pilot signal to control the max charge rate.

 

[mitch672]

That's an interesting idea. You could also modify the pilot signal to control the max charge rate.

The relay is a simple mod to just interrupt the pilot signal, which simulates unplugging the EV (instead of cutting AC power)

To modify the pilot signal is a different animal... You'd probably be better off just replacing the HPWC controller with an OpenEVSE card, which can have it's pilot signal adjusted via a serial port command, or via WiFi/Bluetooth. Could also be front ended with a Raspberry Pi, if you need a web server interface.

 

[Chris Naps]

You really don't want to be switching the AC power on/off, a better way is to interrupt the pilot signal via a small remote controlled relay. There are numerous ways to do this inexpensivly.. A raspberry pi with a relay control board attached is very inexpensive, and you can install a web server on the RPI for remote control. Also this would be minimal modification to the HPWC, just adding a SPST relay inline with the pilot wire, have it normally closed, so if the controller fails/is disconnected, the HPWCs still work.

Extremely smart.. Have you done this before?

 

[mitch672]

Extremely smart.. Have you done this before?

I have a few RasberryPi's, one is being used for a GPS based NTP server, another one runs the OpenEnergy web server.

I have built my own 75A OpenEVSE (see signature)... Have I modified a HPWC? Nope, but it isn't too difficult, just no need, my OpenEVSE is controllable as far as the pilot signal, and cost me a little over 1/2 what a HPWC costs, of course you have to build it yourself, so there is some labor involved as well.

Here is the 75A version I built: https://code.google.com/p/open-evse/wiki/75AOpenEVSE

 

[ohmman]

My HPWC is on its own circuit (obviously), and I have a Brultech Greeneye Monitor (GreenEye Monitor Package - Brultech Store) on my panel. I can measure what the circuit is drawing every 5 seconds if desired (I database these), but there is no on/off control. The interesting thing is when you tie your HA system in with the Python bindings for the Tesla API. Then, you can see what the car consumed over the course of charging and compare it to what was delivered "at the pump". My plan with this setup is to test different amperage settings on the car, compare to the delivered power, and measure efficiency. Same with range numbers and SOC for the battery. I'm assuming there's a big gain to be had here as far as efficiency and savings goes, and I haven't seen it published elsewhere.

Things have been nuts lately but I do plan to get my test suite in place this summer and should have decent data after a few months.