Volt & Amp meter to replace charging "blinking lights"

[TonyWilliams]

This install should be easy enough for any somewhat handy person to install.

My local Toyota dealer has been told not to touch my car.

Can you install it at the same time as the JdeMO, or on one of your "rare" trips to an Orange County meeting?

I'm sure we can work something out. I know how much Toyota loves our car and to what lengths they will go to in making it difficult.

 

[Tadol]

I definitely want one, probably two - and lights and bright are fine. If its too much, I'll find a piece of window tint to put in front of it. But knowing at a glance just how well a charging station is running is invaluable. It'll help every time I plug in somewhere new -

 

[EnerGene]

Is there a way to monitor or watch the charging?
I'm curious to see what rate certain L2 chargers are charging at......6.6KW or 7.2KW.

Also, is 7.2 or 7.7KW the fastest my 2012 RV4 can cjarge at?
I'm guessing yes but want your experienced opinions.

Thanks

 

[Incredulocious]

Is there a way to monitor or watch the charging?
I'm curious to see what rate certain L2 chargers are charging at......6.6KW or 7.2KW.

Also, is 7.2 or 7.7KW the fastest my 2012 RV4 can cjarge at?
I'm guessing yes but want your experienced opinions.

Thanks

You can charge at 9.6kW, but you won't find public L2 chargers providing that rate. You can do so at home though with a 240V 40A charging cord.

 

[TonyWilliams]

Charge rate is nothing more than voltage supplied while charging multiplied by amps.

The RAV4 EV has a first generation Tesla Model S charger onboard, therefore it can charge at about 85% (onboard charger efficiency) of the following rates:

10kW = 277 volts * 36 amps (single phase of 480 volt commercial power)

10kW = 250 volts * 40 amps (household voltage)

9.6kW= 240 volts * 40 amps (household voltage)

8.3kW= 208 volts * 40 amps (commercial power)

7.2kW= 240 volts * 30 amps (household voltage)

6.2kW= 208 volts * 30 amps (commercial power, typical public J1772 station)

 

[davewill]

Did you power it off the incoming AC or the car's 12v? It would be cool to use one like Glenn put in my OpenEVSE that displays the total power so that when I return after a charge session, I can see how much power was used. However, if it's powered off the AC, the meter will be off when the car ends the session.

I might try doing this on my own. I'm assuming you put a fuse on the AC connection to the meter?

Remember to watch the Blinkenlights!

ACHTUNG!
ALLES TURISTEN UND NONTEKNISCHEN LOOKENPEEPERS!
DAS KOMPUTERMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKEN.
IST NICHT FÜR GEWERKEN BEI DUMMKOPFEN. DER RUBBERNECKEN SIGHTSEEREN KEEPEN DAS COTTONPICKEN HÄNDER IN DAS POCKETS MUSS.
ZO RELAXEN UND WATSCHEN DER BLINKENLICHTEN.

 

[GlennD]

Did you power it off the incoming AC or the car's 12v? It would be cool to use one like Glenn put in my OpenEVSE that displays the total power so that when I return after a charge session, I can see how much power was used. However, if it's powered off the AC, the meter will be off when the car ends the session.

I might try doing this on my own. I'm assuming you put a fuse on the AC connection to the meter?

Remember to watch the Blinkenlights!

ACHTUNG!
ALLES TURISTEN UND NONTEKNISCHEN LOOKENPEEPERS!
DAS KOMPUTERMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKEN.
IST NICHT FÜR GEWERKEN BEI DUMMKOPFEN. DER RUBBERNECKEN SIGHTSEEREN KEEPEN DAS COTTONPICKEN HÄNDER IN DAS POCKETS MUSS.
ZO RELAXEN UND WATSCHEN DER BLINKENLICHTEN.

Lately I have been using a LCD display that has volts, current, power, and a resettable KWH. From eBay they cost me $16.88. They cost less than the older LED voltage and current displays. You can see one on the OpenEVSE I have listed for sale. The blue LED lighting is switchable and yes I fuse the power. I was using an inline pico fuse but I needed to distribute power so I made up a fuse- power board this time. That said, I have never in three years have had a display blow up so the fuse is just to make me feel good.

It requires 80-260VAC so it is not powered from 12V DC. The newer unit is continuously powered. I have found the older one with the timer can also be continuously powerwed. The timer is load switched on. I thought it ran continuously so I ran switched power.

The big problem with the Chinese displays is a complete lack of documentation.

 

[TonyWilliams]

It requires 80-260VAC so it is not powered from 12V DC. The newer unit is continuously powered. I have found the older one with the timer can also be continuously powerwed. The timer is load switched on. I thought it ran continuously so I ran switched power.

The big problem with the Chinese displays is a complete lack of documentation.

Just buy any low powered inverter, 12vdc to 120vac.

Here's a quality 140 watt unit that can also run a small plug in appliance, $45 from Digikey. Obviously, there is really cheap Chinese stuff that will do the job, too.

http://www.tripplite.com/shared/product-pages/en/PV140.pdf

 

[GlennD]

Since the input voltage is used for voltage, power, and KWH displays to be accurate it must be line powered. the only thing accurate with an inverter powered unit is current.

 

[TonyWilliams]

Since the input voltage is used for voltage, power, and KWH displays to be accurate it must be line powered. the only thing accurate with an inverter powered unit is current.

All good points.

The only thing I want to see is volts / amps when plugged in. I can make a good estimate of how long I need to sit there, or whether I should immediately move on to another site.

I find very little use in having a display of anything when I return to the car. The only data that is worthwhile then is how many of the sixteen little segments are lit up in the gas gauge.

 

[jgblair]

The only data that is worthwhile then is how many of the sixteen little segments are lit up in the gas gauge.

I wish we had a digital display of the battery level like we do in the first generation RAV4-EV's (with the add on Palm and software) instead of or in addition to the 16 segments.

John
John Blair

 

[GlennD]

Since the input voltage is used for voltage, power, and KWH displays to be accurate it must be line powered. the only thing accurate with an inverter powered unit is current.

All good points.

The only thing I want to see is volts / amps when plugged in. I can make a good estimate of how long I need to sit there, or whether I should immediately move on to another site.

I find very little use in having a display of anything when I return to the car. The only data that is worthwhile then is how many of the sixteen little segments are lit up in the gas gauge.

Since the older volt amp display cost $20 and the new one is cheaper then why not use it? Power is easy since the unit is corrected to a power factor of one but having it show is a nice perk. Also in bright light the display turns reflected even if the blue back light is on.

 

[GlennD]

I have noticed like the iPad the edge of the display turns blackish when very hot. I bet it bright sunlight it might turn totally black like the iPad does. Every thing has its plus and minus points.

 

[miimura]

The only data that is worthwhile then is how many of the sixteen little segments are lit up in the gas gauge.

I wish we had a digital display of the battery level like we do in the first generation RAV4-EV's (with the add on Palm and software) instead of or in addition to the 16 segments.

John
John Blair

RavCharge will show you the SOC in integer percentages. However, you have to pay for ongoing SafetyConnect service and the RavCharge annual fee.

 

[Incredulocious]

The only data that is worthwhile then is how many of the sixteen little segments are lit up in the gas gauge.

I wish we had a digital display of the battery level like we do in the first generation RAV4-EV's (with the add on Palm and software) instead of or in addition to the 16 segments.

This is a curious thing. It does sound cool to have a digital percentage display on the dash showing state-of-charge, much as we do for battery-operated computing devices. But then, on the other hand, we've never had the same for the fuel guages in our gas-burning vehicles and you don't really hear people clamoring for a digital percentage readout there. Arguably the 16-segment display is more precise than the analog display with mere quarter marks.

Funny that. Change the energy storage from a liquid fuel tank to a battery and then an analog display is somehow insufficient. Is it just the limited range of our vehicles? Would it matter less if we got 400 miles on a charge and each of the 16 segments represented about 25 miles?

Just thinking out loud...

 

[miimura]

The only data that is worthwhile then is how many of the sixteen little segments are lit up in the gas gauge.

I wish we had a digital display of the battery level like we do in the first generation RAV4-EV's (with the add on Palm and software) instead of or in addition to the 16 segments.

This is a curious thing. It does sound cool to have a digital percentage display on the dash showing state-of-charge, much as we do for battery-operated computing devices. But then, on the other hand, we've never had the same for the fuel guages in our gas-burning vehicles and you don't really hear people clamoring for a digital percentage readout there. Arguably the 16-segment display is more precise than the analog display with mere quarter marks.

Funny that. Change the energy storage from a liquid fuel tank to a battery and then an analog display is somehow insufficient. Is it just the limited range of our vehicles? Would it matter less if we got 400 miles on a charge and each of the 16 segments represented about 25 miles?

Just thinking out loud...

Actually, the analog gauge representing the digitally calculated SOC on the e-Golf is very accurate. You can estimate the level to better than 1/32. There is also a trick to see the integer percentage through their web site and it agrees with this estimation. This is way better from a resolution standpoint than the bars on the RAV. Ergonomics? Well, that's another story.

 

[jgblair]

RavCharge will show you the SOC in integer percentages. However, you have to pay for ongoing SafetyConnect service and the RavCharge annual fee.

My wife wanted the SafetyConnect service so I have already renewed it. Although most everyone prefers free over paying for things, my issue with RavCharge is that, as I understand it, it requires a smartphone. My cellphone is an old-fashion flip phone. I live in a rural area where cell coverage is often iffy. We only got a tower in town two years ago. I rarely need the other smartphone features so I haven't wanted to pay an extra $40 per month. My wife has an iPhone and she uses it. I have an iPhone 4s that I bought to use as a camera so it only operates on wifi. I also have a wifi iPad. I think that RavCharge requires a cell connection to work? My schedule is erratic plus I am a volunteer firefighter. My cars need to be charged all of the time so I can't take advantage of scheduled charging. I should look into RavCharge in more detail. Thanks for the suggestion.

John
John Blair

 

[jgblair]

Funny that. Change the energy storage from a liquid fuel tank to a battery and then an analog display is somehow insufficient. Is it just the limited range of our vehicles? Would it matter less if we got 400 miles on a charge and each of the 16 segments represented about 25 miles?

If we had 250-300 mile range like many ICE vehicles and if there were fast chargers on every major intersection like there are with gas stations then we would probably not need the resolution of a digital display (except for gear heads and engineers ). Since I have been driving electric since 1980, I have more "instrumentation anxiety" than "range anxiety". I am not afraid of running out of juice. I just want to know where it will happen...

John
John Blair

 

[Incredulocious]

RavCharge will show you the SOC in integer percentages. However, you have to pay for ongoing SafetyConnect service and the RavCharge annual fee.

My wife wanted the SafetyConnect service so I have already renewed it. Although most everyone prefers free over paying for things, my issue with RavCharge is that, as I understand it, it requires a smartphone. My cellphone is an old-fashion flip phone. I live in a rural area where cell coverage is often iffy. We only got a tower in town two years ago. I rarely need the other smartphone features so I haven't wanted to pay an extra $40 per month. My wife has an iPhone and she uses it. I have an iPhone 4s that I bought to use as a camera so it only operates on wifi. I also have a wifi iPad. I think that RavCharge requires a cell connection to work? My schedule is erratic plus I am a volunteer firefighter. My cars need to be charged all of the time so I can't take advantage of scheduled charging. I should look into RavCharge in more detail. Thanks for the suggestion.

RavCharge operates via the internet. Whether you choose to access the internet via WiFi, cellular, wired ethernet or whatever is up to you and matters not to RavCharge. However, it seems the interest here was about seeing a percentage display of your current state of charge, presumably while driving. I don't think stopping to refresh the display via RavCharge (round trip from the phone to the cloud to the car and back again) makes a lot of sense for this purpose.

Besides, it seems easy enough to see that 1/4 of the 16 bars visible is roughly 1/4 charge, etc. Which is why I was saying it's interesting how many people would still prefer to see a percentage display... me too, not that it's needed at all. It's interesting. And when trying to estimate whether your destination is in range, the built-in range estimate (what everyone loves to complain about) isn't all that terrible. I'd call it reasonably useful, certainly more so for most people where what good would "23%" do for estimating whether you can make it to your destination? Folks just need to be aware that the range estimate adjusts to your driving conditions as you go and can't be taken as prescient.

Also, you can use inexpensive cellular plans for even the latest "smartphones". I have a 2 GB/month data plan, unlimited calling/messages, etc on Sprint for my iPhone 6S for $28/month after taxes which is good for two years. (That's for the plan, the iPhone 6S I paid outright for and it is of course much more expensive than a more basic cellphone.)

Hope some of that is helpful!

 

[jgblair]

RavCharge operates via the internet. Whether you choose to access the internet via WiFi, cellular, wired ethernet or whatever is up to you and matters not to RavCharge. However, it seems the interest here was about seeing a percentage display of your current state of charge, presumably while driving. I don't think stopping to refresh the display via RavCharge (round trip from the phone to the cloud to the car and back again) makes a lot of sense for this purpose.

I agree. It would need to be a display connected to the car. I don't know if you are familiar with the 1st Gen RAV4-EV. There is only a "fuel" gauge, a voltage gauge, and no GOM. You can buy a used Palm for $25 off of eBay, buy the cable that connects to the car and get the software. It was easy to plug in and make work. The hardest part was deciding where to mount the Palm so it was easy to see. It displays a lot of info like battery temperatures, SOC, and many other things. I usually just look at the SOC. With my 2002 RAV, it gets about 100 miles per charge, so a SOC tells me about how many miles I have left. In the 2nd Gen RAV, if we could set our own miles/kWhr in the GOM, that would work also. Sometimes it is really low like 83 and sometimes over 100. That tells me what I did in the past, but not what I will do today. It is too variable for my taste. It seems like there could be a better way. A display that we could access and set with our personal knowledge of our future drive would work great. In the meantime, a SOC digital display is the closest we can come to it.

Also, you can use inexpensive cellular plans for even the latest "smartphones". I have a 2 GB/month data plan, unlimited calling/messages, etc on Sprint for my iPhone 6S for $28/month after taxes which is good for two years.

Only Verizon works in my area, so that limits my choices. Still a cell connection should not be needed for a SOC meter. Somebody smarter than I am could probably do the same thing for the 2nd Gen RAV as was done for the 1st. Maybe it is harder to do or simply less interest.

Hope some of that is helpful!

It was. Thank you!

John
John Blair