[DaveSlinger]

Hello,
Thought maybe I'd get a second opinion from some of you high tech Bolt gurus. I have a JuiceBox 75 and the unit / Bolt was working fine for the first month (other than only taking 25 amps in every situation- battery half, battery low, etc.). Noticed since April the charges have been starting and stopping multiple times during the night (while monitoring through the JuiceBox system). JuiceBox tech have been scratching their heads and finally came back with the reply below.


What do you guys think? I'm going to take it to the dealer but I have a feeling, they are going to charge the car and say there is nothing wrong. I hope not, but I feel I'm going to be caught in the middle... Some of what they are saying is above my head and maybe you guys know what they are talking about. Anyone else have an issue like this?
Thank you
DAVE


I've been shopping this around the engineering team and have come up with a few possibilities. There's nothing on our end interrupting these sessions. The logs show clean unit responses, and the car is going from charging, to plugged in and not charging randomly.

Some odd things they noticed, though:

- though the Bolt has a 32A charger and unit is set to 30A limit, the car is only taking about 25 amps (24.7~24.8A).

- the power factor is low, around 0.66, which is strange since EV onboard chargers are power-factor-corrected, and usually have PF of 0.99 or so.

- the voltage drop on the line is around 10 volts when it puts load on the line. That's also pretty bad, indicating a possible wiring problem. Note that this is an input-side voltage sensor, meaning it's before the relay, meaning it can't be the JB's fault at this side of the sensor.

So, some options:

1) the car is interrupting charging because of some smart-charging policy of its control? But this is a bit unlikely. The charging is only interrupted for a few minutes.

2) the car is interrupting charging due to malfunctions - which does seem plausible given the behavior of the session: low amperage, poor power factor, and the long 1st session but shorter subsequent bursts, indicating it's cooling-down and retrying.

3) the car is interrupting charging due to low voltage, like the Tesla does when it de-rates. However, this seems a bit unlikely...

I've seen stories of Bolt manufacturing issues, electronics problems and really erratic behavior. Last week, a 2017 Leaf customer stopped by and tried one of our shop JuiceBoxes, and found that the onboard charger was totally glitching out (audible zapping sound under the hood, erratic charging rate). So, car-based issues are definitely not out of the question.

IMO, the car is suspect the most here, in a defect sense.

 

[DaveSlinger]

Here is the charging email errors...

 

[ChiBolt]

Using the OnStar app, there is a notification system that allows you to receive an email from the car/OnStar when it has stopped charging due to an interruption.

I'm curious if the car sees this an an interruption also and send you an email. If it does, and you have access to another EVSE, plug into another EVSE (or try the 120V charger) and see if the car also experiences and notifies you of an interruption when connected to a different EVSE.

 

[NY-Rob]

10v drop in input voltage to the juicebox is pretty high, put a voltmeter on the 240v line... note the voltage, connect the car and see if you're actually dropping 10v on the input.
When I setup my Juicebox 60 for the Bolt I had a voltmeter on the input line... no significant voltage drop noticed upon start of charge.

You may have a wiring problem leading up the the Juicebox.

Was your Juicebox factory assembled or did you have to built it from components like I had to do back in 2012?
The older units were very sensitive to ground faults, since 240v relies on the ground wire for each leg of the circuit... you may have a problem there too... especially if you're actually seeing a 10v drop in voltage when charging.


I'd bring the Bolt to Chevy and if it charges without problems on their L2 EVSE... it's not the car- it's an easy way to eliminate it from the equation.

 

[jimmyspeed]

Something of concern to me is that a power factor that low is not normal. The grid tries to restrict power much closer to 1, and generally within +/- 0.90 because they generally bill on Watts consumed not VoltAmps and the car is also trying to pull close to 1 PF. I would be skeptical of a system that is pulling 0.66 PF.

It is hard to get a full picture about what is actually happening based on what is provided, but it looks like the car, at one point accepted 4.05kWh in 30 min - which is a rate well over a 25 amp charge rate. Assuming 240V that would need to be 33.75A!

I wonder about the way the electronics work inside the EVSE. If you are pulling significantly more VA than you are Watts (based on the pf provided), maybe something is overheating and thus shutting down?

As ChiBolt said. I would try plugging it into a different EVSE and monitoring it for similar interruptions. That would tell you very quickly if the car is at fault (problems still exist) or the EVSE (car charges normally). I'm not 100% sure if the 120V charger would find the same issues if the car is at fault. I get the feeling that heat is related and the 120V system might not generate enough heat.

 

[ChiBolt]

As NY-Rob mentioned, a 10V voltage drop is alot. Is the wire size going from the electric panel to the Juicebox properly sized? If you have the Juicebox set at 30A, 8 gauge wire on a 40A breaker would be the minimum.

As Jimmyspeed noted, I would be skeptical of the .66 PF. Either the reading is incorrect or there is definitely a problem. Maybe try turning the breaker to the Juicebox off and then back on after a couple of minutes. While not connected to the car, of course.

 

[DaveSlinger]

Hello All,
Called Chevy to speak to a Bolt expert to schedule appointment. They were not in but the regular service guy told me to look at the owner's manual.
*groan


ChiBolt- The emails are coming from the JuiceBox . I'll check into that OnStar app and make sure it's on. It might give a backdoor clue. I don't have any other 240v chargers but I did try plugging in the factory 110v charger. It doesn't give any notifications but it seems to charge okay. Hey, that gives me an idea. I can disconnect the charger, take it to a friends house, hook it up and charge the car. That might tell me if it's a home wiring issue or the JuiceBox unit...


In your second reply: I'm going to double check the wiring to the breaker. It's an older house and I think the guy that had it before me used a welder on that dedicated circuit before. I did replace the fuses in the cut off switch and I also turned off the circuit breaker for a bit and back on again, yesterday.


HMMMMM you've given me another idea- I have not tried plugging in to the 240v dryer outlet yet. That might be another option to try.
Thank you for your help


NYRob- That's sounds like an easy test, putting a volt meter on the line and turning on the charger. I'll try that also- in addition to a visit to Chevy dealer... The JuiceBox that I have is a factory built one.
Thank you sir.


JimmySpeed- A little over my head but I'm going to print it and add it to the material that I'm going to take to the dealer.
Thank you for your observation.


I'll run some of these checks and tests this weekend and keep you posted.

 

[discodanman45]

The first thing I would do is call an electrician out. If you have this hooked up to a 30 Amp breaker with improper gauge wiring this is probably your problem. Did you have an electrician install this or was it a DIY project? Please don't plug it into your dryer outlet, there are many reasons for this!


I really think this is an electrical problem for your house. Older homes weren't designed for this much power usage. For proper level 2 charging you need 200 amp service for your home, a dedicated 40 amp breaker, and proper gauge wiring. From your description it seems you are 0 for 3 here.

 

[DucRider]

The quickest way to eliminate the Bolt is to charge at an EVSE known to be good at 30-32 amps.

My first inclination is the wiring issue, but I would also explore the possibility of a defective charging connector.

The Fit EV had a software update to correct an issue where is was stopping charging (usually at Blink stations). The Fit implements a thermal sensor on the J1772 port (not required by the SAE standard) and it would stop the charge session when it detected too high of a temp. The software fix allowed the car to reduce the charge rate to lower the temp instead of stopping the session completely.

If the Bolt includes such a sensor, there could be an issue with the "nozzle" on your Juicebox creating high resistance/heat and the Bolt could be stopping/starting charging based on inlet port temp. The pins could be dirty, but more likely a poor connection/crimp on one of the AC pins. Blink had a large batch of connectors that worked fine at 3.3 kW, but when EV's started asking for higher charge rates, the problem showed up.

 

[jimmyspeed]

I really think this is an electrical problem for your house. Older homes weren't designed for this much power usage. For proper level 2 charging you need 200 amp service for your home, a dedicated 40 amp breaker, and proper gauge wiring. From your description it seems you are 0 for 3 here.

I don't think this is necessarily a fair conclusion. If these issues are happening at midnight and early in the morning when it is pretty much the only power draw in the house, even a 50A rated panel should be able to handle the charging (assuming proper breaker and wiring sizes for safety). There is no reason to have a 200A panel just because you have a temporary use appliance that draws 30A. An electrician will be able to help determine if there are any code issues for your area. Code issues and functional issues are 2 different things.

It is possible that there is a wiring issue in the house, but I would think that it is unlikely. Breaker size and wire size are important, but beyond that hooking these things up is actually very simple. Line 1, Line 2 and ground. I don't want to suggest that the OP does any self investigation due to limited knowledge and experience, but with a voltmeter one should be able to check for proper line voltages and check to confirm that your ground isn't floating.

I am suspect of the Juicebox myself. Go to a different 240 charging station and monitor the charge. If the problem is gone, you will need to get an electrician to check your home wiring. If there is no issue with the wiring and sizing, try getting a new EVSE. It is probably a better bet than trying to have someone repair a faulty unit - unless there is still a warranty.

Just my 2 cents.

 

[NY-Rob]

As ChiBolt mentioned.... 8 gauge wire on a 40A breaker would be the minimum.
That's exactly what I have on my Juicebox... the 8ga feeder (about 38ft total run from the breaker panel) doesn't even get warm when charging the Bolt.

If you have a longer run with less than 8ga, you're going to see an input voltage drop when charging at full rate.

 

[ChiBolt]

I really think this is an electrical problem for your house. Older homes weren't designed for this much power usage. For proper level 2 charging you need 200 amp service for your home, a dedicated 40 amp breaker, and proper gauge wiring. From your description it seems you are 0 for 3 here.

I also agree that there is a good chance that it is a house/wiring electrical issue. Although a 200 Amp service would be preferred, a 100 amp service is sufficient as long as the other electrical loads are small.

 

[ChiBolt]

As discodanman45 noted, I would not use the dryer outlet. Call an electrician. A dedicated 40A circuit is required.

 

[discodanman45]

Sorry about suggesting that a 200 amp service is required, it is preferred. Where I live it is required where you need to run an air conditioner at night and still charge your car. I would bring my car to any level 2 charger and let it charge for a few hours. If it charges fine I would really suggest you call an electrician out to take a look at the wiring. Just to warn you, if they have to wire your older house to code (especially in a state like California) it may get expensive with permits. I am a physicist, so I know how electricity works and what needs to be done. However, I am a theoretical physicist so I hire electricians to do the work for me

 

[NY-Rob]

I have a 1964 home w/100 amp service.... no problems charging the Bolt from it.

You have to keep in mind that as electrical devices have become more efficient- our overall loads have been reduced significantly.... even if your electric bill hasn't decreased. Currently, my 4 upstairs bedrooms are cooled by a very efficient 4-head mini-split unit that only draws 12amps at full load. Back in the day that 12amps would have probably been tripled to cool four rooms.

 

[devbolt]

The first thing I would do is call an electrician out. If you have this hooked up to a 30 Amp breaker with improper gauge wiring this is probably your problem. Did you have an electrician install this or was it a DIY project? Please don't plug it into your dryer outlet, there are many reasons for this!


I really think this is an electrical problem for your house. Older homes weren't designed for this much power usage. For proper level 2 charging you need 200 amp service for your home, a dedicated 40 amp breaker, and proper gauge wiring. From your description it seems you are 0 for 3 here.

I'm on 125A service and have no problems charging. I did have a fresh 40A circuit put in for the EVSE.

I agree, it sounds like something is screwy with the circuit feeding the OP's EVSE, or the house's electrical system.

 

[jimmyspeed]

I really doubt the house wiring is at fault here - I haven't seen a response about if this was DIY or electrician installed, but this is basic basic stuff for an electrician. I'm sure that there would be other issues in the house if the house service was at fault. If it is only the single circuit - I'm just not even sure what would cause these symptoms.

I feel pretty confident that the EVSE is at fault here. (I'm no genius, but I do have an undergraduate degree in Electrical Engineering if that means anything)

 

[DaveSlinger]

Hello All,
Back again...


Did a test just now and put voltmeter on the line. Voltage fluctuated for 240 to 245 before turning on the JuiceBox. Turned it on and the power dipped to 238 once very quickly then fluctuated between 240 and 245 again. The phone app showed the yellow blinking bar a few seconds then it stopped (charging stopped). I put the app on stop and redid the test. Same thing… Noticed on the phone charging app it says error but no code or anything.


I’m going to disconnect the JuiceBox charger after charging the car tonight (obviously intermittently) and take to another house and connect. That should eliminate any house wiring problems at this home, I think. If it charges fine, then maybe there is an issue with the wiring here at this house.
Will keep you posted.


DISCODANMAN45- The outlet is on the outside of the garage under an awning, pre-wired and already there when I purchase the 1950's house in the 1970's. Everything was checked out when inspected and electric appeared to be good enough to pass inspection. However, I did have solar panels installed a few years ago and they upgraded the breaker box from a 100 AMP to a 200 AMP and there are about 5 slots available for extra stuff and are not being used. It's actually on a 50 AMP dedicated breaker to that fused cut off switch where the JuiceBox is wired to (if that makes any difference).


Thanks for the tip on using the dryer outlet, I will bypass that test.


DucRider- I don't have access to another charger but just remembered I saw a charger at the mall near here. Do you think that would work? I have not sat in the car while it's charging so I don't know if the dash display will say anything or not (just thought of that actually). I do look at the car out the window at night occasionally and there doesn't appear to be anything unusual with the blinking green, charge indicator light. It's steady and consistent. The only way I can tell the charging going off and on is through the JuiceBox email alerts, website graphs and the phone app. I think if I charge at the mall, it will look like it's getting a normal charge?


Very interesting theory on the connector. I always make sure I push it in until it clicks into place. I'll note your comments for the dealer to investigate once we rule out the house wiring or the JuiceBox as being the problem. I think, moving it to a different location and trying to charge might help.
Thanks for the ideas.


JimmySpeed- Does the test I just did showing the voltage fluctuating from 240 to 245 mean that it's a "floating ground?" Should the voltage be holding at a solid 240 until the load is put on it but then stabilize again?


As mentioned to DucRider, I'm not sure if using a non-monitoring charger will tell me if the charge is starting or stopping. I've never actually took a close look at a mall charger, do they have a meter on them or something like that? If so, maybe it will tell me if the charge is stopping and starting. I know there are fast and regular charges at those places. I imagine I would have to use the fast charge vs the slower charge since I don't notice any problems using the slow factory 100v charge at home. I wonder if those use two different circuits one for 100v and a separate circuit for 220v?


I've attached the JuiceBox email notos from today's test.
Thank you all for your help and advice.
DAVE

 

[jimmyspeed]

JimmySpeed- Does the test I just did showing the voltage fluctuating from 240 to 245 mean that it's a "floating ground?" Should the voltage be holding at a solid 240 until the load is put on it but then stabilize again?


As mentioned to DucRider, I'm not sure if using a non-monitoring charger will tell me if the charge is starting or stopping. I've never actually took a close look at a mall charger, do they have a meter on them or something like that? If so, maybe it will tell me if the charge is stopping and starting. I know there are fast and regular charges at those places. I imagine I would have to use the fast charge vs the slower charge since I don't notice any problems using the slow factory 100v charge at home. I wonder if those use two different circuits one for 100v and a separate circuit for 220v?

Hi Dave,

240 volts is good - having voltage drop under load isn't going to tell you if you have a floating ground. The way to check that is to use the volt meter to check that the ground line is 0 volts different than a known ground source (like a metal water supply line (usually)). There should be a ground wire connected from the panel to a ground rod in someway.

Some public chargers will tell you the charge rate. I thought that the car (which I don't have yet) actually tells you how many KW the car is charging at when plugged in. If the car isn't charging I'm pretty sure int wont look like it is. Keep an eye on the display, see what it says.

 

[DaveSlinger]

Update from JuiceBox came in last night to the 110 volt charging question:


The reason the 120v charger is working fine is that it doesn't supply enough power to put a strain on the Bolt's onboard charger. At those low charging speeds, it would have no trouble keeping itself cool. I think, with a cooling system problem in the Bolt's charger, it could be overheating and shutting down. At least, that's my running theory at the moment...


I don't know how accurate these charging EVSE charging indicators are but this time I attached a JuiceBox website graph showing the intermittent charging from last night / this morning (05-05-17 / 05-05-16). The black line says Energy (kWh) when I hover over it and the orange line says Power (kW). In snapshot 1, if I hover over the very right side of the graph where the black line is at the top (it also shows a dot on the orange line below it) it gives me a reading of Energy kWh 32.23 and Power kW 4.09 at time 01:31:52 I noticed on the graph, the Energy (kWh) seems normal (?) the black line climbing steadily. However, the orange line Power (kW) seems to be what is having problems with spiking, charging, then shutting down abruptly. Not quite sure what this means but I'm sure you guys do...


I also attached a screen shot of the JuiceBox website "gauges" showing Amps, kW, Temp and Volts to the car at the same time 01:31:52.


The car when put on the charger was exactly 3 banks down on power according to the car battery level (I had a 1/4 "tank" left of range, in other words 5 bars). The JuiceBox charger kept working at it (off and on) since I manually started charging at 10:00 PM 05-05-17 and it finally finished at 05-06-17 at 05:00 AM and it added 203 miles of range according to the phone app. In addition, the phone app says the charge added 85% t the battery, voltage currently (?) is 247, the battery temp is 104 degrees and the frequency (Hz) is 59.98, the session Energy (kWh) 51.09 and the charging time is 06:10 (however, I turned it on at 08:00 PM and it's 05:00 AM now- so the car should have been charging for 9 hours?). I remember a couple of months ago when I first got the car and charger, it would fully charge from this level during my TOU period from 10:00 PM to 05:00 AM when I would unplug to go to work. So I would imagine all this stopping and starting is dragging out the charge time that it's plugged in, but the charger is saying it only took 6 hours to charge?


I had not noticed that temperature reading on the phone app in the past. I should see if that's in real time the next time I charge and if it will tell me if the battery is getting hot. It doesn't look like the website tracks this temperature in a graph format. I suggested it to JuiceBox for maybe a good update in the future that might help with troubleshooting. I'll watch that tonight when I charge from the other location.


Finally, I attached the email notifications that I get when the JuiceBox is shutting off and turning back on again. If any of this is helpful to you while figuring this out, then I'll include them in future tests.
.
I will be disconnecting the JuiceBox today to take to a friend's house to connect and charge tonight to see if there is anything different.
Just an FYI update...
THX
DAVE