[VinTC]

Hello everyone, long time no post. My Chargepoint CT500 (aka Siemens 8M1111) EVSE worked flawlessly for over 5 years but it gave up the ghost the other day. Good voltage at the terminals and the ground checks ok, just a blank display and no output. I called Chargepoint and they said there are no user replacable parts... the rep quickly steered me toward a new CP Home EVSE and offered a 15% discount, but I figured I'd check here to see if anyone knows of a quick fix.

Anyone interested in my old CT500 minus the cord and J1772?

 

[freshcut]

Have you opened the box to see if there might be a fuse inside that possibly blew? Although manufacturers frequently say there are no user serviceable parts, occasionally they have a soldered fuse to the board somewhere. From a technical standpoint, this is not user replaceable since it can't be removed without desoldering, it's still replaceable if you have basic electrical skills.

 

[kns]

...Good voltage at the terminals and the ground checks ok, just a blank display and no output....

There won't be any voltage at the output unless the EVSE is connected to a vehicle.

The CT500 is built like a tank. It is rated for 7.2KW and has a heavy duty cable and plug as well as options for network connectivity and for commercial, public, and exterior installations. Other than an early warranty replacement for excessive hum, mine has been otherwise faultless in daily use for more than five years. The CT in the model designation stands for Coulomb Technologies, now known as ChargePoint. If are not able to find parts or documentation searching ChargePoint, a search based on the original brand name might be more fruitful.

If you are inclined to debug and repair your unit, the installation guide at the below url which includes LED trouble messages might be helpful.

https://www.chargepoint.com/files/CT500-Installation-Guide.pdf

If you are not so inclined, you should be able to get good value for the case, cable and plug even if the internal electronics are not functional.

A third alternative might be to install one of the kits now on the market into the CT500 case. If you decide to consider this alternative I recommend that you consider only kits that carry a UL listing for the entire package and not just for the components.

Whichever path you decide to follow, keep in mind that the NEC and NFPA require that EVSEs be UL listed and that is not something you should want to debate with your insurance company following a fire event.

Please report back with what you decide to do and the end result.

Thank you and good luck.

KNS

 

[freshcut]

Since my post, I was actually curious if there is any known issue for the CT500 and it turns out there is a 5V power supply that is a known weak point.

This page shows the internals and describes a couple testing procedures if you're so inclined.

http://forums.aeva.asn.au/forums/chargepoint-ct500-repair_topic4837.html

The power supply in question looks to be about $50-100 depending on where it's sourced.

 

[VinTC]

Thanks for the replies. Fourm member Chris TX has offered to repair my unit for $75 including return shipping. Beats the heck out of a new EVSE!

 

[Chris TX]

She lives!

 

[VinTC]

Ha! That's the first time I've seen more than 3.3kW out of it. You must've plugged it into your Tesla.

 

[Chris TX]

Ha! That's the first time I've seen more than 3.3kW out of it. You must've plugged it into your Tesla.

Yeah. I've just used a 12AWG tail for it, for testing and it's set to 16A in the car.

 

[Chris TX]

Ha! That's the first time I've seen more than 3.3kW out of it. You must've plugged it into your Tesla.

Your PM inbox is full. I just want to make sure your shipping address is the same as on your check. PM me back, either way.

 

[VinTC]

I mounted it today and it's working like a charm. Thank you, Chris!

 

[bitguru]

So what did Chris TX actually do to fix it?

My Coulomb CT500 stopped working last Saturday. It's a different mode of failure than VinTC experienced, though.

The LCD screen is fine. It cycles through the following messages:

| Available | Remove connector from holster and plug into vehicle. | CHEVROLET VOLT _ | Network disconnected. station will continue to charge. You may be eligible for rebate when upgrading to ChangePoint Home. | CHARGEPOINT | STATION : 852C |

(I lower-cased some stuff while transcribing.) This EVSE was originally part of a DOE grant, and it has a cellular connection to a site (which I haven't looked at in years) that could show using information.

When I plug this CT500 into a 2011 Volt, I hear the "thunk" of the contactor closing and the dome signal goes orange momentarily, then goes dark permanently. When I plug this CT500 into a 2013 Focus Electric, I hear the "thunk" of the contactor closing but the blue status ring remains dark. (I think the first time I tried the Focus Electric the entire circle blinked twice, but not now.)

I guess this would be consistent with a blown high-voltage fuse inside the CT500 unit, but I don't know if it has one.

 

[Chris TX]

So what did Chris TX actually do to fix it?

My Coulomb CT500 stopped working last Saturday. It's a different mode of failure than VinTC experienced, though.

The LCD screen is fine. It cycles through the following messages:

(I lower-cased some stuff while transcribing.) This EVSE was originally part of a DOE grant, and it has a cellular connection to a site (which I haven't looked at in years) that could show using information.

When I plug this CT500 into a 2011 Volt, I hear the "thunk" of the contactor closing and the dome signal goes orange momentarily, then goes dark permanently. When I plug this CT500 into a 2013 Focus Electric, I hear the "thunk" of the contactor closing but the blue status ring remains dark. (I think the first time I tried the Focus Electric the entire circle blinked twice, but not now.)

I guess this would be consistent with a blown high-voltage fuse inside the CT500 unit, but I don't know if it has one.

The main, low voltage power supply was dead. Desolder/soldered in a new power supply. I'm happy to diagnose and at least attempt to repair it. I'm quite familiar with the guts of those units, now.
PM me if you're interested.

 

[bitguru]

From the pictures over at http://forums.aeva.asn.au/forums/chargepoint-ct500-repair_topic4837.html I'm not so sure there's a high-voltage fuse. [edit: I hadn't realized that this very same link was posted earlier in this thread. Oops.]

It could be that the contactor isn't connecting, even though it goes "thunk."

 

[kns]

So what did Chris TX actually do to fix it?

My Coulomb CT500 stopped working last Saturday. It's a different mode of failure than VinTC experienced, though.

The LCD screen is fine. It cycles through the following messages:

(I lower-cased some stuff while transcribing.) This EVSE was originally part of a DOE grant, and it has a cellular connection to a site (which I haven't looked at in years) that could show using information.

When I plug this CT500 into a 2011 Volt, I hear the "thunk" of the contactor closing and the dome signal goes orange momentarily, then goes dark permanently. When I plug this CT500 into a 2013 Focus Electric, I hear the "thunk" of the contactor closing but the blue status ring remains dark. (I think the first time I tried the Focus Electric the entire circle blinked twice, but not now.)

I guess this would be consistent with a blown high-voltage fuse inside the CT500 unit, but I don't know if it has one.

Got my CT500 through the same DOE program. My working unit goes through the same display sequence as yours. The cell modems in these units are no longer being polled for usage data. The clunk you hear is the relay connecting to deliver power to the vehicle. The fact that no power is being delivered to either of two vehicles suggests that the fuse in the CT500 has opened.

KNS

 

[bitguru]

The fact that no power is being delivered to either of two vehicles suggests that the fuse in the CT500 has opened.

I just opened the CT-500's cover and measured the voltage at the contactor outputs. When it first clicks it measures 240V, and when shortly thereafter it clicks again the voltage drops to zero. So the contactor itself would seem to be fine.

Are you saying there's a fuse on the car side of the contactor? (I would expect any fuse to be on the hot side of the contactor, but what do I know?)

[update: The DC power supply is putting out a steady 4.96 volts.]

 

[bitguru]

Comparing my CT-500 to the one at http://forums.aeva.asn.au/forums/chargepoint-ct500-repair_topic4837.html I see some differences.

The CT-500 over there has a small modem mounted to the main PCB, with an antenna wire connected. Mine has the small modem mounted too, but it doesn't seem to be used. Instead is a external CMDA wireless modem made by MultiTech systems, with power connection and possibly RS232 data connection to the main PCB, and antenna wire connected. (I say "external" because it's metal box with external-like connectors [DB-9 and coaxial] even though it is mounted inside the CT-500's enclosure.) I doubt this has anything to do with my problem.

The other CT-500 only has one current sensor, which one of the high-voltage wires (the brown one) goes through.

Mine has two current sensors. One is like that of the other CT-500, with the brown high-voltage wire going through, and the current sensor's wires plugging into the "pilot" PCB. The other has three wires going through it. Those are both of high-voltage wires (brown and blue) and a thin white wire. The current sensor's two wires, and also the two ends of the thin white wire, plug into a small daughter card that is attached (oriented 90°) to the other side of the pilot PCB.

There are a surface-mount LED and two pins connected with a jumper on the pilot PCB, very close to the daughter card.

I wonder if there could be some problem with the current sensors which is somehow causing the firmware to cut off the contactor. If so, the LCD panel is not reporting anything unusual. It reports something innocuous like "done charging."

 

[dcooper8]

Hi Chris,

My name is Dave Cooper, I'm in Metro Detroit with a 2015 Volt and Coulomb CT500 in my garage. My CT500 seems to be having the same issue as described -- completely dead, no LED display. I have tried cycling the circuit breaker to no avail.

Would you be willing to try a repair on my unit as well? I will need some instructions on how to dismount it from the wall and prepare for shipping to you.

Best Regards,

Dave

 

[Chris TX]

Hi Chris,

My name is Dave Cooper, I'm in Metro Detroit with a 2015 Volt and Coulomb CT500 in my garage. My CT500 seems to be having the same issue as described -- completely dead, no LED display. I have tried cycling the circuit breaker to no avail.

Would you be willing to try a repair on my unit as well? I will need some instructions on how to dismount it from the wall and prepare for shipping to you.

Best Regards,

Dave

Hi Dave, you have a PM.

 

[panzer948]

Hi Chris, just sent you a PM

 

[bitguru]

I'm still having trouble resurrecting my Coulomb CT500. It occurred to me to check the conductors in the J1772 cable, so I just did, and they seem ok. The ground, power1, power2, and pilot wires have continuity between the J1772 connector to the CT500 interior. Measuring between the proximity pin and the ground pin reads 150 ohms at rest, 480 ohms when the release button is pressed, as expected. So I guess the cable is not the problem.

Since the power supply seems to be good (4.96 volts) I'm not sure why things are going wrong. I guess I should consider replacing the Coulomb PCB with a replacement (such as openEVSE) but I'm reluctant because it's _almost_ working with the Coulomb PCB.