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Discussion Starter · #1 ·
Hi all, I believe some chargers require a fuse saver wire to be routed along with the supply cable from the CU to the charge point.

Please could someone clarify what type of wire is required as I plan to pre-install whilst renovation work is in progress.

Or, is the fuse saver wire still relevant as from what I understand chargers have been 'smart' chargers since 2019 and therefore balance the charge?

Thank you.
 

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By "fuse saver" I presume that you mean current limiting? Only a few charge points offer this and only use it either for solar or where the incoming fuse is very restricted. Where they do they use a CT clamp which is best wired using its original wires although these can be extended via some low voltage cabling (not bell wire).
"Smart" chargers are significantly misnamed and do not have to include this feature, only the ability to report usage back to the owner.
 

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Discussion Starter · #3 ·
Hi. Thanks for your reply.

Yes, auto current limiting.

I'm new to this and as I was reading up on chargepoints I came across a post where it mentioned a fuse saver wire is installed alongside the supply wire specifically for the purpose of balancing the current. I didn't know about the usage reporting via this means as well.

Then I learn't elsewhere that since 2019 all smart chargers must automatically balance the current draw according to the overall loading, therefore I now believe the fuse saver wire may perhaps be a redundant thing from the past.

As I am pre-installing SWA cabling along with ethernet cable I thought this fuse saver wire (if still required) is not left out!

I'm confused 😕!

Thank you.
 

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Either 0.5 mm 2 core cable or cat 5/6 shielded.

You can buy cable from Doncaster cables that has the data or the cat 5/6 inside the swa. If your going to go this route get the one with cat 5/6 inside as I'm getting alot of problems with the 2 core.
 

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"Smart" means whatever the supplier of the kit wants it to mean! Some will balance a limited supply between 2 EVSEs so the combined charging doesn't blow your main fuse, some will talk over your wifi to servers & report stats to you, some will schedule charging for low-tarriff times, some are liable to get temporarily suspened if the DNO runs low on power in some emergency, some will vary the charging current acc to how mush spare solar energy you have, etc. Confusing isn't the only word for it !!! Mind-boggling, befuddling, headache-inducing, ... :cry:
 

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Or just plain stupid.
The earlier OLEV grant required the theoretical ability for the charge point provider to remotely reduce the charge being drawn, but that ended about 4 years ago since when all that is required is for usage statistics to be available remotely.
The load balancing described above is not an OLEV/OZEV requirement and is not standard or even optional on most. It's only required if the total load possible exceeds the rating on the incoming fuse. This is a strange requirement as it takes no account of diversity and just sums your load 64A for two 7kW charge points, the full 16A for an electric oven, 13A for an immersion, 40A for an electric shower etc even if there's no chance that you would want to run them all at once.
The main issue is whether you are likely to get need this feature, and why remote surveys ask you to list all of your appliances.
Some load balancing is done at the charge point by hard wiring the CT (e.g. PodPoint), some via WiFi (e.g. Zappi), and others via a wired ethernet connection (SmartPlus). So unless you buy your charge point now it's hard to know what to install.
 

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Discussion Starter · #7 ·
Thank you all for your comments and advice. I think the best bet is to decide what chargepoint I would like and take it from there with the supplier. I already bought my swa cable but I will also need to buy the ethernet cable too.
 
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