EHU Plug-in - a silly mistake

[StuartO]

Our EHU plug-in on the side of the MH was not working properly; After plugging in I almost always had to wiggly the thing about to get the mains to connect. It happened with two different EHU cables, so it seemed to be the fitting on the MH. I took it off and checked the cable connections on the back, which seemed OK. I also checked both of the socket ends of the EHU cables. Nothing appeared to be wrong. But the fault persisted so clearly something was wrong.

 

Today I faced up to removing the EHU fitting completely and taking it to bits. Nothing was broken inside and the brass connection pins and the cable connections to them appeared to be perfectly OK. I decided to use our short connecting cable with a blue plug at one end and a 13a domestic plug at the other to do a continuity check using my multimeter.

 

As I plugged the blue plug into the dismantled EHU wall fitting on the bench it became clear that the blue plug could get misaligned as it went into the wall fitting and the spring loaded blue lid could then prevent the plug going fully home. It was snagging half an inch short and therefore making a poor electrical connection - hence the problem I was encountering. When you insert the blue plug of the EHU cable (technically it’s actually a socket) on my MH there is a yellow flap that gets in the way of the view, which is how I was inserting it against what felt like a stop (but was actually half an inch short) and failing to make a good electrical connection.

 

So if you ever have this problem, look carefully as you make the insertion and make sire the spring loaded lid isn’t misaligning as you go in. It’s not obvious from the outside view that you are not in far enough.

[potus4388]

Good tip, a point to take note of.

Thanks!

 

[Derek Uzzell]

There’s valuable advice on the A&N Caravan Services website about mains hook-up cables

 

http://www.aandncaravanservices.co.uk/hookup-leads.php

 

I have two mains hook-up cables - a 10-metre one that I try to always use and a 25-metre one that I try to avoid employing as it’s heavy and awkward to coil up afterwards so that it can go back into its storage bag.

 

https://ducksback.co.uk/?product=cable-storage-bag-copy

 

On the ‘motorhome end’ of the shorter cable I’ve removed the hinged ‘lid’ from the connector (shown in attached photo). This makes it easier to insert the connector into the motorhome’s mains socket and it also means that, should I ever drive away without disconnecting, the cable should detach from the motorhome without causing damage (Maybe!). I’ve left the ‘lid’ on the longer cable’s connector just in case I want to connect it to the 10-metre cable.

 

 

 

[Keithl]

Stuart,

 

The lid has a small protrusion which is intended to hook over the plug or male half of the socket to prevent accidental disconnection. It sounds like the 'ramp' designed to engage the hook has got damaged or is misshapen on your inlet socket and that the lids hook is not engaging fully. Could you try gently pressing the release lever as you insert the plug to get it to engage fully?

 

Derek,

 

Removal of the lid from the trailing end of the lead is really not a good idea IMO. It prevents objects being inserted into the sockets of the lead when it is disconnected and also accidental disconnection as stated above.

 

Keith.

[StuartO]

I have acquired several EHU cables, adapters etc and I usually carry a combination of 10 and 25 metre lengths - although of course on French campsites you occasionally need more than 35 metres to reach a power point, which is why French MH owners often carry a reel of 50 metres or more.

 

The “normal” EHU cable in UK is 2.5. mm sq, which is quite heavy. The French seem to use much thinner/lighter cable, so 1.5 mm.sq or even 1.0 mm sq. My MH has a 10 amp circuit breaker on the EHU input circuit, so 1.5 mm sq is plenty thick enough for me.

[Alanb]

Stuart,

 

If you plug a 15A rated 1.5 sq mm EHU cable into a 16A rated site bollard, it is technically not fully protected. The window for overloading is small, but if a ready made 1.5 sq mm cable was sold, it could be described as not fit for pupose. (Your onboard 10A MCB is meant to protect your onboard insallation, not the EHU cable.

 

The heating of an EHU cable, and volts drop along it will increase in inverse proportion to the csa of the cable conductors.

 

Alan

[Derek Uzzell]

C&MC guidance on hooking up to the mains can be found here

 

https://www.caravanclub.co.uk/uk-holidays/useful-information/hooking-up-to-the-mains/

 

and the cable-related advice is as follows

 

B* CONNECTING CABLE harmonised code H07RN-F or H05VV-F or equivalent (BS6007 or 6500) 25 metres maximum (+ or – 2 metres) long of three core cable (live (brown), neutral (blue) and earth (green/yellow)) each core of 2.5mm squared section.

 

Shorter cables may not reach from the bollard to your van on some sites and extra connector cables to add length are not permitted.

 

However (as StuartO says) the norm for hook-up cables marketed in France is for the cores to have a 1.5mm squared section and for single-piece cables (rubber or plastic sheathed) to be up to 50 metres in length. When an advert gives a 1.5mm2 cable’s amperage, this is invariably stated as 16A.

 

When the cable is on a reel (and the long cables usually are) it’s near certain that, if only 10 metres of a 50-metre cable were needed for the hook-up, 40 metres of cable would remain tightly wound on the reel.

[Tall_Mike]

I can see the issue happening - The EHU socket into the van wasn't as tight as it might be on our old van but we didn't have any issues, - so maybe it was fine. Can see it wearing after a lot of use.

 

I carry one 25mtr cable, it is awkward, and heavy, horrible when it's wet and cold, but it's a "proper" heavy duty cable. We have had occasions when it hasn't been long enough, more common on the continent, some of the German sites are a complete rat's nest of cables snaking everywhere, lucky enough to be able to borrow a 10mtr extension although don't think joining them together is really a good idea.

 

We are quite happy on solar, - so if the cable didn't reach, while an annoyance for sure, it wouldn't be the end of the world for a night or 2.

 

I personally wouldn't take the cover off the cable - it holds it in to the socket, - if someone trips over the cable for example it wont pull out - although I take the point of driving away with it connected, - I came very close to doing that a couple of years ago, - remembered in the nick of time.

 

I have wondered if cables could have a sacrificial joint ? - So it the is a massive pull on the cable for some reason, it snaps, better to buy a new cable than van damage

 

 

[StuartO]

I suspect that the UK is the only country in Europe where there is an official rule (or is it guidance?) that an EHU cable must be 2.5 mm² guage, no more than 25 metres in length and using multiple cable to extend beyond 25 metres is not allowed - and that motorhomers from these other countries would find these UK 'council of perfection' constraints laughable.

 

I bought a 25 metre long 1.5mm² EHU cable by accident (off EBay, thinking it was 2.5mm²) but having found how much lighter and easier to handle it is (and having evaluated the electrical risk/benefits) I will certainly continue using it as my primary EHU connection. If I want to carry an extra extension I would certainly consider a reel of 1.0mm², as French motorhomers use.

 

A minor point about the spring-loaded flap lid on the end which inserts into the MH wall fitting; they vary in design and while some can be lifted with the right index finger to detach them, some cannot and require more careful poking and lfiting with the other hand.

[Keithl]

StuartO - 2019-06-13 4:00 PM

 

A minor point about the spring-loaded flap lid on the end which inserts into the MH wall fitting; they vary in design and while some can be lifted with the right index finger to detach them, some cannot and require more careful poking and lfiting with the other hand.

 

Stuart,

 

You should not need to be 'poking' your finger in to release the latch, there should be a release lever to lift the flap for you. On ours it is a blue lever on the left of the plug.

 

Keith.

[Geeco]

It is interesting to draw a comparison between the UK power cords/fittings and those used in AU. The fitting used is a 3 pin type although different to the UK version. The motorhome fitting is covered with a flap that lifts to accept a female connector that has no schroud or spring loaded flap. Most of the caravan parks provide a stand that has power outlets, fresh water & a grey water drain at the bottom of the stand. Usually you would share the stand with two bays and two behind max 4 bays. The Kmac unit shown below is considered the best and most common. I am in UK, Cotswolds at present and while travelling by car I have looked over the fence at several caravan parks to see how you set up. Personally I prefer the spring loaded shrouded lead connector as fitted to my Autotrail MH to the AU version.  Our 15 amp fittings have a larger earth pin to stop the cables being connected to a 10 amp circuit. Cheers

PS thanks for the wonderful English summer guys!!

[StuartO]

Keithl - 2019-06-13 4:39 PM

 

StuartO - 2019-06-13 4:00 PM

 

A minor point about the spring-loaded flap lid on the end which inserts into the MH wall fitting; they vary in design and while some can be lifted with the right index finger to detach them, some cannot and require more careful poking and lfiting with the other hand.

 

Stuart,

 

You should not need to be 'poking' your finger in to release the latch, there should be a release lever to lift the flap for you. On ours it is a blue lever on the left of the plug.

 

Keith.

 

There is a slot to the left in the moulding of the receiver which looks like it could accommodate something to do with a release mechanism. Maybe mine was missing something when first installed?

[Keithl]

StuartO - 2019-06-14 9:48 AM

 

Keithl - 2019-06-13 4:39 PM

 

StuartO - 2019-06-13 4:00 PM

 

A minor point about the spring-loaded flap lid on the end which inserts into the MH wall fitting; they vary in design and while some can be lifted with the right index finger to detach them, some cannot and require more careful poking and lfiting with the other hand.

 

Stuart,

 

You should not need to be 'poking' your finger in to release the latch, there should be a release lever to lift the flap for you. On ours it is a blue lever on the left of the plug.

 

Keith.

 

There is a slot to the left in the moulding of the receiver which looks like it could accommodate something to do with a release mechanism. Maybe mine was missing something when first installed?

 

Stuart,

 

It should look like this...

 

Keith.

[Alanb]

Keithl - 2019-06-13 4:39 PM

 

StuartO - 2019-06-13 4:00 PM

 

A minor point about the spring-loaded flap lid on the end which inserts into the MH wall fitting; they vary in design and while some can be lifted with the right index finger to detach them, some cannot and require more careful poking and lfiting with the other hand.

 

Stuart,

 

You should not need to be 'poking' your finger in to release the latch, there should be a release lever to lift the flap for you. On ours it is a blue lever on the left of the plug.

 

Keith.

 

Keith,

 

May I point put that on my 2006 PVC, which I have owned from new, there is no release lever.

 

Alan

[Keithl]

Stuart,

 

Does the 'slot' you mention look anything like the photos I posted, if so it may be that your release lever was missing from day one and could be the reason for your poor connection problem.

 

My suggestion would be to get the complete inlet unit replaced with one containing the lever, they are not that expensive at most caravan dealers or even Amazon, etc.

 

Keith.

[StuartO]

Keithl - 2019-06-14 10:29 AM

 

Stuart,

 

Does the 'slot' you mention look anything like the photos I posted, if so it may be that your release lever was missing from day one and could be the reason for your poor connection problem.

 

My suggestion would be to get the complete inlet unit replaced with one containing the lever, they are not that expensive at most caravan dealers or even Amazon, etc.

 

Keith.

 

I think mine is a different design. It has a lockable swivelling outer cover and an inner yellow flap. This photo is of a replacement currently available on EBay for £48. mine is not broken so I won't be replacing it.

[Derek Uzzell]

UK on-line adverts suggest that the norm nowadays is for the EHU hook-up connection to have a ‘release-lever’ as shown in Keith’s photos above. However, I don’t remember my 1996-built Herald’s hook-up point having a release-lever or cable retention feature of any sort.

 

My Rapido’s hook-up connection has the commonplace blue release-lever, and I suspect that its predecessor (a 2005 Hobby) also had one and that was when I removed the ‘lid’ from my 10-metre hook-up cable.

 

The Rapido’s hook-up connector is similar to the first of Keith’s photos, with a lightly-sprung hinged cover. Unless the cover is properly clipped down (when it can be difficulty to unclip) it will flap madly when the Rapido is driven. The cover also has the potential to rattle in high winds when the Rapido is parked and on hook-up, so I restrain it using a rubber strap that came from one of my VW cars in the distant past. I also use the strap to hold the coiled cable together.