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Discussion Starter #1
Following on from this thread, in which I received lots of helpful advice (culminating in me digging a trench and Sparky laying chunky armoured to outbuildings), things progressed yesterday:

A Podpoint pair travelled from Bristol (to my location west of Swansea) to install my charger.

They were efficient in one sense (quick and goal-focussed ?) but didn't want to look inside the house, just checked the mini-CUs in the outbuildings and took my word for it that despite the long cable run the voltage at my preferred install point was 231v (as tested by my electrician.)

They duly installed the unit nearly where I wanted it but said that they needed to install a main switch in the second garage, as they couldn't run their unit off the mini-CU directly (something about interference and DC-AC interaction causing problems in the house and difficulty fault-finding in the future.)

However, they didn't have a main switch and said they'd have to come back with one (paid for by Podpoint, apparently) but that it would only be an hours work.

It all sounded very plausible but then AI know sweet f.a. about these things!

This where we are now:

(new box, lower of the two, awaits wiring-in of adjacent black cable once internals for white box arrive.)

Charger in situ (I will need to run some sealant into that cable-hole to stop moisture tracking down and in, as they had none):



I'm sure it's all above board but if this sounds odd please let me know (I was surprised they didn't want to look in the house, particularly when I answered "no" to their question "was a survey done by podpoint first".)
 

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(I was surprised they didn't want to look in the house, particularly when I answered "no" to their question "was a survey done by podpoint first".)
Plausible deniability.
As neither PP or they looked into it then if there is a problem it must be your electrician's responsibility. :sneaky:
 

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and took my word for it that despite the long cable run the voltage at my preferred install point was 231v (as tested by my electrician.)
Meaningless if it wasn't under load at the time. They need to test it under the planned load as a piece of bellwire would show the voltage in the main CU at no load.
Charger in situ (I will need to run some sealant into that cable-hole to stop moisture tracking down and in, as they had none):
Bunch of cowboys. Were they PodPoint staff or contractors? That cable should loop up before entering the hole in the wall. Send the photo above to PodPopint and ask them to rectify it before you will accept the work.
 
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Discussion Starter #4
Meaningless if it wasn't under load at the time. They need to test it under the planned load as a piece of bellwire would show the voltage in the main CU at no load.
Thanks.

So does that mean it won’t work? I won’t get the car for at least a month (probably more...) so won’t be able to test. I assume they will test (under load) once installation is complete.

Is the voltage drop under load due to thermal effects or something else?

Bunch of cowboys. Were they PodPoint staff or contractors? That cable should loop up before entering the hole in the wall. Send the photo above to PodPopint and ask them to rectify it before you will accept the work.
I assume they were contractors (can’t recall uniform/van livery but it didn’t say Pod-Point)

What does “loop up” mean in this context. Create a point on the cable lower than the hole, to stop water tracking-in or is that an electricians term.

Since they will have to come back anyway I can push for rectification, not sure if I know enough about it to argue about voltage drop under load!
 

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Thanks.

So does that mean it won’t work? I won’t get the car for at least a month (probably more...) so won’t be able to test. I assume they will test (under load) once installation is complete.

Is the voltage drop under load due to thermal effects or something else?



I assume they were contractors (can’t recall uniform/van livery but it didn’t say Pod-Point)

What does “loop up” mean in this context. Create a point on the cable lower than the hole, to stop water tracking-in or is that an electricians term.

Since they will have to come back anyway I can push for rectification, not sure if I know enough about it to argue about voltage drop under load!
Voltage drop comes from Ohm's Law: V=IR. The voltage across a resistor — in this case, your cabling — is equal to the current times the resistance. If your cable has a resistance of 1 ohm, there will be no voltage drop at zero current, but a catastrophic 32V if you pull 32A for a nominal 7kW charge.

We can't say it will or won't work: it depends entirely on the size of installed cable. But measuring end point voltage under no load is pointless: wet string would show the same voltage if you could find a way to measure without drawing any current at all.
 

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Discussion Starter #7
Is there a good reason why they could not drill a hole at the height of the podpoint?
Probably not a good reason. When I get the chance I’ll check the inner wall of the garage; maybe there’s is something in the way there.

I noticed that the unit has its cable entry hole in the side, at 5 O’clock position. It would be more elegant if it could enter directly into the back of the unit, avoiding any externally visible cabling but maybe there is a reason why not.
 

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You’ve had contractors sent.

That job could have easily been completed.

They should have entered the pod through the back.
 

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I noticed that the unit has its cable entry hole in the side, at 5 O’clock position. It would be more elegant if it could enter directly into the back of the unit, avoiding any externally visible cabling but maybe there is a reason why not.
The main body of the PodPoint can be mounted at any orientation (as you have discovered) and the front at a different one. You really need a new unit if they are going to enter from behind as they have removed a knockout on the current one.
Given your lack of EV at the moment make sure that they bring a proper tester to check it under full load. They used to have PHEVs as vans that had the advantage of doing a real world test.
 

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The main body of the PodPoint can be mounted at any orientation (as you have discovered) and the front at a different one. You really need a new unit if they are going to enter from behind as they have removed a knockout on the current one.
Given your lack of EV at the moment make sure that they bring a proper tester to check it under full load. They used to have PHEVs as vans that had the advantage of doing a real world test.
Contractors don’t have PHEV’s.
 

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Probably not a good reason. When I get the chance I’ll check the inner wall of the garage; maybe there’s is something in the way there.

I noticed that the unit has its cable entry hole in the side, at 5 O’clock position. It would be more elegant if it could enter directly into the back of the unit, avoiding any externally visible cabling but maybe there is a reason why not.
They have 3 entering points inside the pod.

3, 6 and 9 o’clock positions. About a inch in.
 

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Is the voltage drop under load due to thermal effects or something else?
Voltage drop comes from Ohm's Law: V=IR. The voltage across a resistor — in this case, your cabling — is equal to the current times the resistance. If your cable has a resistance of 1 ohm, there will be no voltage drop at zero current, but a catastrophic 32V if you pull 32A for a nominal 7kW charge.
The above 1 ohm resistance is just used as an example, and is much more than it would be in practice.

Do you know the length of the cable from your main DB to the garage?, and it's size?

From my old copy of the wiring regs, the resistances and voltage drops are as follows:

4mm^2 cable: 0.011 ohms per metre, or 3.52v per 10 metres at 32A
6mm^2 cable: 0.0073 ohms per metre, or 2.33v per 10 metres at 32A
10mm^2 cable: 0.0044 ohms per metre, or 1.41v per 10 metres at 32A
 

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Contractors don’t have PHEV’s.
Maybe not, but they should have a way of testing the unit under full load. Clearly it's up to PodPoint to ensure that their contractors do the job to an appropriate standard so as not to damage their reputation. I would question it in this case.
 

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So there’s a mcb feeding a garage dB and a mcb from the first garage feeding a 2nd garage?

4mm is crazy to feed lights, sockets and 7kw charger with no ct clamp. There would never install on that.
 
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