Blown plug on granny charger

[K9pvc]

Hi everyone,

I’m looking for some advice. For the past 8 years, I’ve been charging my 2016 Outlander with the OEM “granny” charger that came with it. However, after returning home with a flat battery today, I plugged it in as usual and left it to charge overnight. When I unplugged it in the morning, I found it hadn’t charged at all. Upon inspecting the charger, I noticed that none of the usual lights were on.
After a closer look, I found that the fuse area in the plug seems to have overheated, and the fuse holder now looks damaged and burnt.

My question is: would it be safe to just replace the plug and see if that fixes the issue, or is that a bad idea? I’d really appreciate any advice on what to do next. Alternatively, if anyone knows a reliable place near Manchester (UK) where I can get it checked or repaired, that would be really helpful.

Thanks in advance!

 

[DaveL59]

Hmm I've noted that the plug and short mains cable to the charger does get quite hot in the early stages of charging but so far its OK. Do you have access to a meter to check there's no shorts across the pins in the mains plug?

While you could lop off the moulded plug and replace with a high quality UK plug, you'd need to ensure the wires are well clamped in since it'll be drawing 10A for a couple hours at a time. Likewise the strain relief as hanging the brick (if you do that) would be too much for a regular UK plug, probably.

Also re-check for shorts before plugging it in to be sure no false positives/negatives with the old plug attached.

If there's a local electrical repairer it might be worth getting them to check it over in case theres any issues inside the brick that caused the failure. They may be able to PAT test it etc and at least give some confidence it's still in good order.

 

[Daixiwen]

It could also have heated up because of a bad connection between the plug and the socket, or to the wires in the socket itself. If I were you I would check the socket before changing the plug. It does get a bit hot when charging but it should never become that hot.

 

[littlescrote]

^^^^ this ^^^^

The plug is just half of the equation

 

[BruceHF]

This is what I like and expect a foram like ours, that when someone has an issue at a the time is unsolvable, then the suggestions come (good or bad) . Again I say 'suggestions ' or 'ideas' that one can either take it or leave it. I value the input even though in this case I have no idea but eagerly waiting to see what suggestions come up even though I don't currently have this problem.
Why am I bringing this up? There are come critics that don't believe in this interaction that bicker and argue about forthcoming reports, experiences etc. Carry on guys!

 

[MrPastry]

Replace both the plug & socket with good quality items. Don't buy cheap.

We regularly check single & 3 phase connectors/plugs/pumps etc on site with a thermal imaging camera.
For heavy loads, both plugs & sockets are regarded as consumables.


A great tool if you can borrow one.





P.

 

[davebodger]

Replace the plug and socket with new good quality items (MK comes to mind). Check the wires in the back of the socket are OK and not blackened or burnt.
The thing that gets hottest in normal use is the fuse, so a black plug will help radiate heat.
Make sure the stranded wires have ferrals crimped on.
Make sure all the screws in everything are tightened up but not so tight they cut through the wires (the ferrals help stop this).
You're going to be putting 10 amps through this for up to 5 hours at a time, so do what you can to keep the temps down in the area where the socket is.
The plug will get hot where the fuse is - an IR thermometer will likely show 45 to 50C. If it gets over 60C you likely have a problem and need to check all connections are tight. Be careful as 60C and above can give you burns.

Don't run the EVSE (Granny charger box) from an ordinary extension lead. Typical 1.25mm2 extension cables will get very hot on 10 amps and are not really designed for continuous use. I use a 2.5mm2 caravan hook-up lead as an extension cable and that does not get noticably hot. I replaced the 13A plug at the EVSE with a Commando plug which goes into the caravan hook-up cable which comes with those connectors as standard. On the other end I fit the 2.5mm cable into a 13A plug. It's a tight fit but you can just do it. Obviously this reduces the general purpose utility but I made a short adapter so I can carry it around in the car and charge where ever needed, leaving the 25 meter hook-up lead at home.

This may not apply to you, but the place where the cable mostly breaks is at the gland into the EVSE box. You need an electrician to fix this (unless you are competent with electrical repair yourself) - the EVSE is sealed with black mastic "gunk" so you can't get the halves apart even after taking out all the screws. It takes lots of time and careful leavering with screwdrivers to get them apart without damage. This is mostly caused by hanging the EVSE from the plug lead like at a public charging station. If you can, support the EVSE during charging so there is no strain on the cable going to the plug. If the cable does break there, get it replaced with about 1.5m of 2.5mm2 cable, so the EVSE can be laid on the ground so there is less weight on the cable.

 

[AndyInOz]

Probably not applicable in your case, but just in case:

Remember:

Do not ever hang the charger box from the electrical cable.

The box has holes in the frame, to allow a suitable 'hanging cord' to be used for that purpose.

 

[yardbird]

You should always use a GFCI circuit breaker for your charging cable. This GFCI breaker saved mine at about the fifth year, it burned out once & I just replace another GFCI breaker last year.

 

[PHEV07]

Hi everyone,

I’m looking for some advice. For the past 8 years, I’ve been charging my 2016 Outlander with the OEM “granny” charger that came with it. However, after returning home with a flat battery today, I plugged it in as usual and left it to charge overnight. When I unplugged it in the morning, I found it hadn’t charged at all. Upon inspecting the charger, I noticed that none of the usual lights were on.
After a closer look, I found that the fuse area in the plug seems to have overheated, and the fuse holder now looks damaged and burnt.

My question is: would it be safe to just replace the plug and see if that fixes the issue, or is that a bad idea? I’d really appreciate any advice on what to do next. Alternatively, if anyone knows a reliable place near Manchester (UK) where I can get it checked or repaired, that would be really helpful.

Thanks in advance!

Any update on on this post? Did you end up changing the plug?

One thing that you did not mention was whether you were using an Extension Cord or not.

If absolutely needed, be certain that the one that you use can handle a full 15Amps. with length total length less than 25'

 

[FlyinSpanner]

You should always use a GFCI circuit breaker for your charging cable. This GFCI breaker saved mine at about the fifth year, it burned out once & I just replace another GFCI breaker last year.

A GFCI is usually USA terminology for what is called an RCD in the U.K.

 

[FlyinSpanner]

In the U.K. the best type of socket to plug your granny charger into should be a BS1363/EV type.
Typically a single socket (avoiding over current) you will find that number moulded onto it. Around £15.

Avoid any diy store ‘own brand’ cheapo- they just won’t stand up to continuous high load.

If you use an extension cable ensure it’s at least 2.5mm and never leave it on the reel charging, unwind it and lay it out.
Left rolled up it will heat itself

 

[littlescrote]

A GFCI is usually USA terminology for what is called an RCD in the U.K.

RCD or RCBO?

 

[michael8554]

RCD will sense earth leakage.
RCBO will sense earth leakage AND over-current, so is a combined RCD and MCB.
I believe a GFCI is a RCD.

 

[yardbird]

RCD will sense earth leakage.
RCBO will sense earth leakage AND over-current, so is a combined RCD and MCB.
I believe a GFCI is a RCD.

• Ground Fault Circuit Interrupters (GFCIs) The GFCI detects imbalance in the current flowing from hot to neutral, imbalance in the current flowing from hot to neutral and quickly cuts off electricity, thus reducing the risk of electrical shock. It saved my Mit PHEV charger once after using it for 5 years and I just replaced the portable GFCI for some $15. The portable GFCI was partly burned & black & stripped.

 

[crun]

You should always use a GFCI circuit breaker for your charging cable. This GFCI breaker saved mine at about the fifth year, it burned out once & I just replace another GFCI breaker last year.

A primary function of the charge unit is as an RCD.
As illustrated in the photo, there really is no point in plugging it directly into a cheap RCD.
You are protecting nothing, and the cheap RCD is just increasing the number of connections and components that are not really suitable for continuous operation at rated current. You are increasing the chance of fire, without materially reducing the risk of shock.

 

[yardbird]

A primary function of the charge unit is as an RCD.
As illustrated in the photo, there really is no point in plugging it directly into a cheap RCD.
You are protecting nothing, and the cheap RCD is just increasing the number of connections and components that are not really suitable for continuous operation at rated current. You are increasing the chance of fire, without materially reducing the risk of shock.

How can you tell the GFCI is cheap from the photo??

 

[crun]

How can you tell the GFCI is cheap from the photo??

It is of course possible that it is an industrial unit with a datasheet, and a specific rating of xxA continuous operation.
Or it might be what it looks like - an RCD made for intermittent use on extension cables, that you might get from a big box store, of rather indeterminate internal design quality, and using the kind of crimped and overmoulded plugs that have form for burning out when used continuously at rated current.
The key point is that the charger is an RCD - and in this type it is a high quality design. (I have opened multiple)

 

[Zulu67MP]

A primary function of the charge unit is as an RCD.
As illustrated in the photo, there really is no point in plugging it directly into a cheap RCD.
You are protecting nothing, and the cheap RCD is just increasing the number of connections and components that are not really suitable for continuous operation at rated current. You are increasing the chance of fire, without materially reducing the risk of shock.

Crun beat me to it (ta) though I would add... apart from poor device design and construction, overheating is most likely to be due to a poor connection forcing too much current through too small a contact area.

This is not uncommon when it comes to mains plugs which, in the UK, need to meet BS1363 specifications. It never ceased to amaze me when safety-training qualified electricians just how many didn't know how to properly wire a plug! It isn't just 'common sense', so unless we have the knowledge and skill we should leave to someone who has.

In a nutshell, ensure full wire contact, avoid soldering the ends (unless you really know how), firmly tighten screws but don't overtighten, ensure long earth wire, routinely examine and confirm at suitable periods.

If a device is properly designed to take 10 Amps, it may possibly get warm, but should never grow too hot to touch.

If someone with a full knowledge of the current IEEE regs, or non-UK equivalent, can usefully add more, please do ... it might just help save a fellow PHEV owner's home or life ... or car

(Sorry for being a bit heavy, but if this helps someone avoid a catastrophe, then all to the good.)

 

[Zulu67MP]

Opps! Accidentally sent before finishing ... I wanted to add that moulded plugs are an unknown quantity insofar as we can't see inside them, so we blindly trust to the manufacturer to have done a good job. Some don't even come with bult-in fuses (though none for PHEVs that I've seen so far). If we remove one and replace it with our own 'properly connected' one, we may void a warranty or cause an insurance company to clap with glee, so Catch 22. Monitoring a moulded plug for overheating is high on my list of safely confirmations when using a new device ... how about you?

Meanwhile, back to PHEV charging, my low mileage would make installing a Type 2 charger a life-time pay-back expense, so I'm sticking with my Granny, which (who?) I have permanently plugged-into an outdoor waterproof switched socket (as described in another post). I'm also happy to stick with mostly daytime electricity costs so that I can react quickly should an, albeit unlikely, failure occur that I might not otherwise know about until its far too late. So far, so good .