Mowcowbell
Well-Known Member
I'll receive my 6-20p adapter today and will test it with my Honda OEM EVSE and post back my results on this thread.
Level 2 Charging for under $20
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Fast Eddie B
Well-Known Member
More data points = good thing!
Being in a regulated field, I have a conservative outlook. Although the science appears reasonable if it can be confirmed that the guts of the US chargers are the same as those used elsewhere, I would not even entertain this idea. There is no way of knowing if there have been any issues from the use of a charger in this manner since I don't believe any companies are reporting fires/etc. to this level of specificity.
The cost/benefit of this approach is wildly outside of what I would consider reasonable. The benefit is what? Saving a couple of hours in charging time? Even in the best case scenario (high gas prices vs. electric cost, you take off as soon as the jury-rigged charging is complete each time, etc.), this would probably be $2.00 or less per charge in gas savings. Frequently it will be less, sometimes much less. The cost is what? Best case scenario? Fried electrical components? Worst case scenario though? Loss of residence and/or personal injury. I had a friend lose a house from a fire due to poorly installed electrical wiring. Although eventually I believe he was made whole from his insurance, he would have paid many thousands of dollars if it would have prevented going through that ordeal. They lost lots of pictures and other personal mementos they have no way of getting back.
It's a risk tolerance thing. Saving a couple of dollars or less each day is apparently worth a lot more to some than it is to others. I have a hard time imagining someone who had the funds to buy this car would be in such a poor financial situation that they couldn't afford a proper install. YMMV.
The cost/benefit of this approach is wildly outside of what I would consider reasonable. The benefit is what? Saving a couple of hours in charging time? Even in the best case scenario (high gas prices vs. electric cost, you take off as soon as the jury-rigged charging is complete each time, etc.), this would probably be $2.00 or less per charge in gas savings. Frequently it will be less, sometimes much less. The cost is what? Best case scenario? Fried electrical components? Worst case scenario though? Loss of residence and/or personal injury. I had a friend lose a house from a fire due to poorly installed electrical wiring. Although eventually I believe he was made whole from his insurance, he would have paid many thousands of dollars if it would have prevented going through that ordeal. They lost lots of pictures and other personal mementos they have no way of getting back.
It's a risk tolerance thing. Saving a couple of dollars or less each day is apparently worth a lot more to some than it is to others. I have a hard time imagining someone who had the funds to buy this car would be in such a poor financial situation that they couldn't afford a proper install. YMMV.
KentuckyKen
Well-Known Member
I just reported what my agent told me and I have no idea of all the verbiage in my policy. The agent told me she checked up the line on this. But she may or may not be the source of all truth and beauty on this issue.
I pressed her further on this issue today and was told my policy covers accidental losses, acts of nature, and criminal acts by third parties like arson. She gave me the impression that it might end up with a bunch of lawyers arguing over the claim as to whether or not it was accidental.
As in I knew the device was clearly marked as not rated for the circuit I plugged it into, had to use an adapter and knowingly choose to not follow the manufacturer’s explicit instructions in the manual. And then my lawyers will be unable to find any credentialed professional witness that will state they recommend this. So she tells me it may come down to a lot of legal wrangling over accidental vs willful. Blah, blah, blah. So is she telling me the truth or is this just bunkum? I don’t know and I don’t want to find out.
But let’s say @Mowcowbell and others and even an EE, report in that it works. Then I go back to my original post that just because it can be done may doesn’t necessarily mean it should be done. The insurance business is all about risk management. I insure myself in various scenarios to reduce my risk of catastrophic or costly loss that I can’t afford, and to reduce the drama and worry in my life that I just don’t need.
There’s different kinds of risks. Low probability and high probability. And each can have large or small consequences. If the N.A. Honda OEM ends up working at 240 V, then it could be viewed as a low risk, but one with dire consequences as in loss of life and house. You can’t replace a life and the house replacement claim may be less than 100% guaranteed. (YMMV)
So for me it’s not worth it to use at home. But this is clearly a personal decision and we will all be looking at it from different viewpoints of common sense and risk aversion. So make an informed decision and we’re all friends at the end of the day.
PS: One is the things I truly appreciate about this forum is the virtually total absence of snarkiness and flaming back and forth posts that has ruined other forums to the point that I left them. Everyone here has been cheerful and helpful without getting on their high horse. And almost all of the time, posters distinguish between their opinions and dogma. Thanks to all for making this the best forum I have found.
Mowcowbell
Well-Known Member
I agree, this forum is a valuable exchange of ideas, opinions and actual test results. Everyone will have their side on this issue, and I think everyone appreciates the other side's opinion.
Fast Eddie B
Well-Known Member
I wonder if one of our tech nerds can come up with a wiring schematic for the charging cord.
I have a friend who was a Honda tech. I’ll see what he thinks.
I have a friend who was a Honda tech. I’ll see what he thinks.
Does Honda sell rechargeable cars in 230/240-volt markets and if so, is the same EVSE delivered in those markets? Why wouldn't Honda reveal that their EVSE is good for 240 volts if it is safe for 240 volts?
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That was one of my questions too. Seems like a bad business decision to not allow/promote that idea and businesses generally don't purposefully make bad decisions.
So I'm an electrical engineer (actually computer design), although not a "qualified" one for any of this 
Basically, an EVSE is:
1) A double pole relay between the wall power and the big terminals of the car connector. Relays contacts have both voltage and current ratings. Current will be the same, and while it's likely the relay is rated for 240V, it might not be. You'd have to tear apart each cord to be sure (if the relay is labeled), because even some have 240V rated relays there's no guarantee the manufacturing run wasn't optimized before or after that.
2) Low voltage circuitry controlling the relay coil, using the small terminals of the car connector for handshaking (this handshaking is what tells the car what current can be drawn). This part shouldn't be affected by the charging voltage (because of #3)
3) A power supply to provide the low voltage for #2. Just like most phone chargers etc automatically handle 120-240V inputs and step down to the same fixed voltage, as in #1 there's no guarantee unless the part in the particular cord is labeled and rated for 240V.
In electronics manufacturing, there's often a single design that is tested during manufacturing, and due to process variation some parts meet spec A and other parts only meet spec B. For example, switching power supply chips that don't meet 240V specs but do meet 120V specs might be binned for use in 120V-only cords. Depending on volumes needed, some 120V cords might have chips that could have met 240V, some might have 120V-only chips. And because it could be on the margin, it might work sometimes on 240V but fail when the outside temperature is a bit higher, or lower, or the house voltage is a little higher or lower. Best case, the out-of-spec voltage just causes the EVSE to stop working, worst case (unlikely but possible) it starts a fire.
I don't mean to be a wet blanket here -- we make risk tradeoffs every day in life, and it's not unreasonable to decide the risk here is low enough to be worth doing anyway, but people should just be aware of the risks. I'd be comfortable doing this myself in a place where I can keep an eye on it, but I probably wouldn't want to leave it unattended, especially in a garage underneath my kids' bedrooms while they slept, for example.
Basically, an EVSE is:
1) A double pole relay between the wall power and the big terminals of the car connector. Relays contacts have both voltage and current ratings. Current will be the same, and while it's likely the relay is rated for 240V, it might not be. You'd have to tear apart each cord to be sure (if the relay is labeled), because even some have 240V rated relays there's no guarantee the manufacturing run wasn't optimized before or after that.
2) Low voltage circuitry controlling the relay coil, using the small terminals of the car connector for handshaking (this handshaking is what tells the car what current can be drawn). This part shouldn't be affected by the charging voltage (because of #3)
3) A power supply to provide the low voltage for #2. Just like most phone chargers etc automatically handle 120-240V inputs and step down to the same fixed voltage, as in #1 there's no guarantee unless the part in the particular cord is labeled and rated for 240V.
In electronics manufacturing, there's often a single design that is tested during manufacturing, and due to process variation some parts meet spec A and other parts only meet spec B. For example, switching power supply chips that don't meet 240V specs but do meet 120V specs might be binned for use in 120V-only cords. Depending on volumes needed, some 120V cords might have chips that could have met 240V, some might have 120V-only chips. And because it could be on the margin, it might work sometimes on 240V but fail when the outside temperature is a bit higher, or lower, or the house voltage is a little higher or lower. Best case, the out-of-spec voltage just causes the EVSE to stop working, worst case (unlikely but possible) it starts a fire.
I don't mean to be a wet blanket here -- we make risk tradeoffs every day in life, and it's not unreasonable to decide the risk here is low enough to be worth doing anyway, but people should just be aware of the risks. I'd be comfortable doing this myself in a place where I can keep an eye on it, but I probably wouldn't want to leave it unattended, especially in a garage underneath my kids' bedrooms while they slept, for example.
Mowcowbell
Well-Known Member
I received my NEMA 6-20p to 5-15 240v adapter, plugged in my Honda OEM EVSE, both the amber and green light came on, plugged the J1772 into the car, and it began charging. The Hondalink App is showing I am charging at 240v. I have had it charging for 30 minutes so far, and have checked the entire cable run for any heating. It's room temperature.
This was the first time I've ran my battery down to 2 bars since purchasing the car 2 months ago. As soon as I started charging, the Hondalink App indicated a '14%' charge.
I'm assuming it is still supplying ~10amps, but at 240v. My wall connector is a NEMA 14-50r connected to a 50amp breaker on my breaker box. I'm using a 14-50 to 6-20 adapter that I linked to in a previous post on this thread.
This was the first time I've ran my battery down to 2 bars since purchasing the car 2 months ago. As soon as I started charging, the Hondalink App indicated a '14%' charge.
I'm assuming it is still supplying ~10amps, but at 240v. My wall connector is a NEMA 14-50r connected to a 50amp breaker on my breaker box. I'm using a 14-50 to 6-20 adapter that I linked to in a previous post on this thread.
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KentuckyKen
Well-Known Member
Keep monitoring through the entire charge or at least near the end and please let us know how long it took to get up to full from 2 bars. I salute your fearless and intrepid efforts on behalf of us more timid folks.
LegoZ
Active Member
To confirm you have a Clarity PHEV and NOT a full electric right? from what I have seen they are different.
The Gadgeteer
Active Member
I have to admit I am intrigued
This thread got me curious enough to pull the charge cable out of the trunk and take a look. Still sealed in the original factory plastic bag.
I seriously doubt that it would make sense for Honda to source 2 different charge cords that when the BEV and PHEV wouldn't take, utilize or need anything different for charging at 120V. This is what came with my Clarity Electric:
Model No. JE-H2A2
Also labeled "EV Cordset 3XB3"
First thing that gets my attention is the UL listing label. Would not qualify if it was labeled for 240V use since it is equipped with a 5-15P. In order to be UL listed for dual voltage, the attached cord must have a 240V plug, and an adapter provided for 120V use (they can't provide an adapter that would inadvertently allow 120V only devices to be plugged into a 240V circuit). I don't have the actual UL rules on this, but this info came from a discussion with some Aerovironment engineers on the design and plugs they chose for their TurboCord product.
IIRC, there was a thread (maybe even on a different forum) where someone did disassemble an OEM charge cord, but couldn't get to the actual relays as the unit was internally sealed with epoxy (circuit board entirely covered) and no way to explore further without destroying the unit.
Out of curiosity, how many of you that are adverse to using it other than directed use it:
1) With an extension Cord
2) At a height of less than 18" from the floor?
Both are contrary to the instructions on the label
David in TN
Well-Known Member
Because of the 120-volt plug, it's going to have its own part number.
I had pondered looking up a 240-volt cable part number, but realized that it would be different just for this reason alone.
If you can prove me wrong, I will be very happy to see!! [emoji846]
Sent from my SM-N960U using Inside EVs mobile app
I had pondered looking up a 240-volt cable part number, but realized that it would be different just for this reason alone.
If you can prove me wrong, I will be very happy to see!! [emoji846]
Sent from my SM-N960U using Inside EVs mobile app
The Gadgeteer
Active Member
I doubt Honda makes these themselves. We might get more info if we can find out who makes them for Honda.
Mowcowbell
Well-Known Member
I live outside of CA or OR, so I have the PHEV version.
Oh, and my house is still standing. The OEM EVSE never got above the ambient temperature in my garage of 78F. I didn't do a full charge with it, as I was leaving the house for the evening and didn't want to leave it unsupervised.
About the only negative I see is that it only charges at ~10amps, not 16amps like the Zencar Level 2 EVSE that I have. A full charge would probably take 5-6 hours with the Honda EVSE connected to 240v. Here's a pic of the unit connected to 240v. The adapter I purchased from Amazon is that small piece between the 6-20 cable and the Honda EVSE:
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My friend's house stood for 4 years before it burned down from the faulty wiring.
Have you calculated how much you're actually saving? How many times a week and for how many hours will you take advantage of the increased charging speed? How much would you save based on your current power rates and gas prices?
Let's say you can only charge for 6 hours a day. So compared to 12 hours for a full charge on 120V, you're gaining essentially half a charge. I think most people report that a full charge is about 15kWh? So 7.5 kWh. Let's say average over the course of a year (summer and winter both) is 50 mile on a full charge (probably pretty optimistic for most folks), so one would be on HV for an additional 25 miles. Using a conservative 40 mpg, that would be 0.625 gallons.
(.625 x <current gas price>) - (7.5 x <current electric rate>) = daily saving.
For me, it would be (.625 x 2.75) - (7.5 x .08) = $1.12 in an absolute best case scenario.
For a more specific calculation based on one's current situation, it would go something like this. Scroll to the bottom if you just want to plug in your numbers.
To figure out how much extra charge you'd be getting, you'd take the hours for a full charge and subtract the actual time you charge each day in hours (let's call this CT), then divide by 12. If you can charge for 6 hours, you'd be getting an extra half a charge [(12 - 6)/12] = 0.5. If you can charge for 8 hours, you'd get an extra 0.33 of a charge [(12-8)/12]. Let's call this BCF (bonus charge fraction). This only works for charging times greater than 6 hours.
To figure out how many extra miles that would save you in HV, you multiply your BCF by your average EV range. Let's call those BM (bonus miles).
To figure out how much that would save you, you'd compare the cost of those BM in EV against the cost of those miles in HV.
HV cost = (BM / MPG) x <current gas price>
minus
EV cost = (15 x BCF x <current electric rate>
For me, I averaged around 48 EV miles in winter (using the Mr. Freeze method) and am averaging 64 this spring, so I'd estimate around 56 EV miles over the course of a year. My HV mpg has been around 45. I can usually charge for 12 hours, but let's say my charging time (CT) is 11 to make this show something.
PLUG YOUR NUMBERS IN HERE
So CT = 11 hours, average EV = 56, HV MPG = 45, Gas = $2.75, Electric = $0.08/kWh. This assumes you start with a completely dead battery.
My BCF is [(12-CT)/12] = 0.083
My BM would be BCF x EV = 4.67
HV cost is BM/MPG x Gas = $0.29
EV cost is (15 x BCF) x Elec = $0.10
Savings = HV cost - EV cost = $0.19 per day in an absolutely best case scenario. Not worth it. YMMV
Have you calculated how much you're actually saving? How many times a week and for how many hours will you take advantage of the increased charging speed? How much would you save based on your current power rates and gas prices?
Let's say you can only charge for 6 hours a day. So compared to 12 hours for a full charge on 120V, you're gaining essentially half a charge. I think most people report that a full charge is about 15kWh? So 7.5 kWh. Let's say average over the course of a year (summer and winter both) is 50 mile on a full charge (probably pretty optimistic for most folks), so one would be on HV for an additional 25 miles. Using a conservative 40 mpg, that would be 0.625 gallons.
(.625 x <current gas price>) - (7.5 x <current electric rate>) = daily saving.
For me, it would be (.625 x 2.75) - (7.5 x .08) = $1.12 in an absolute best case scenario.
For a more specific calculation based on one's current situation, it would go something like this. Scroll to the bottom if you just want to plug in your numbers.
To figure out how much extra charge you'd be getting, you'd take the hours for a full charge and subtract the actual time you charge each day in hours (let's call this CT), then divide by 12. If you can charge for 6 hours, you'd be getting an extra half a charge [(12 - 6)/12] = 0.5. If you can charge for 8 hours, you'd get an extra 0.33 of a charge [(12-8)/12]. Let's call this BCF (bonus charge fraction). This only works for charging times greater than 6 hours.
To figure out how many extra miles that would save you in HV, you multiply your BCF by your average EV range. Let's call those BM (bonus miles).
To figure out how much that would save you, you'd compare the cost of those BM in EV against the cost of those miles in HV.
HV cost = (BM / MPG) x <current gas price>
minus
EV cost = (15 x BCF x <current electric rate>
For me, I averaged around 48 EV miles in winter (using the Mr. Freeze method) and am averaging 64 this spring, so I'd estimate around 56 EV miles over the course of a year. My HV mpg has been around 45. I can usually charge for 12 hours, but let's say my charging time (CT) is 11 to make this show something.
PLUG YOUR NUMBERS IN HERE
So CT = 11 hours, average EV = 56, HV MPG = 45, Gas = $2.75, Electric = $0.08/kWh. This assumes you start with a completely dead battery.
My BCF is [(12-CT)/12] = 0.083
My BM would be BCF x EV = 4.67
HV cost is BM/MPG x Gas = $0.29
EV cost is (15 x BCF) x Elec = $0.10
Savings = HV cost - EV cost = $0.19 per day in an absolutely best case scenario. Not worth it. YMMV
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Mowcowbell
Well-Known Member
It's too bad Honda didn't go with an EVSE like Tesla did with the Model 3. Interchangeable plug heads with an option for NEMA 5-15 or NEMA 14-50.
My experiment only cost me $14 and it proved to me that I could use the OEM EVSE at 240v should I want to.
Will I use it on a daily basis? No, because I already have a Level 2 16amp EVSE which charges at a faster rate. My typical charge scenario is use the Hondalink app and setup a scheduled charge from 4:30am to 5:30am. An hour charge at that rate is about all I need for my daily driving.
My experiment only cost me $14 and it proved to me that I could use the OEM EVSE at 240v should I want to.
Will I use it on a daily basis? No, because I already have a Level 2 16amp EVSE which charges at a faster rate. My typical charge scenario is use the Hondalink app and setup a scheduled charge from 4:30am to 5:30am. An hour charge at that rate is about all I need for my daily driving.