Trickle charger SAE connector

Bossworld · April 24, 2019, 12:31

I've got a Maypole trickle charger which works fine on the MR2 over winter. It came with normal clamp on clips, and a ring terminal harness. I left the ring terminal harness attached to the MR2.

The other day I started up the Mini and got a warning that the charge level was low. Decided to buy another harness - Maypole don't stock them so just got a generic SAE one off eBay.

It seems that Maypole alone, don't adhere to standard.

https://www.webbikeworld.com/battery-tender-sae-harness-installation/

The generic harness I bought follows the above flow.

The Maypole charger (and included harness wire) reverse the +ve/-ve at the SAE connector (:< >

Therefore on the Maypole terminal harness, the covered socket is negative and the exposed pin is positive.

So... is there anything I can do? I could wire up this harness the other way round at the battery, but then I'd be fusing the negative side. That doesn't seem a good idea to me but then again it's 15 years since I did GCSE science so I don't remember which way current flows.

Otherwise looks like buying another charger just to get a spare pare of wires.

paulj · April 25, 2019, 19:37

If you were happy to butcher your new lead, chop and swap the ends across with two compression barrel connectors. Or if your butchery skills are limited just a pair of choc block screw wire connectors.

It would be advisable to keep the fuse in the live side!

But first, are you sure that Maypole have got it wrong? I would have expected them to also avoid having an exposed live terminal from the car floating around on the end of a lead in the engine bay.....

Bossworld · April 25, 2019, 19:48

Quote from: paulj on April 25, 2019, 19:37
If you were happy to butcher your new lead, chop and swap the ends across with two compression barrel connectors. Or if your butchery skills are limited just a pair of choc block screw wire connectors.

It would be advisable to keep the fuse in the live side!

But first, are you sure that Maypole have got it wrong? I would have expected them to also avoid having an exposed live terminal from the car floating around on the end of a lead in the engine bay.....

Thanks for the reply. Yeah it's looking like it'll need a cut and shut, hadn't considered just swapping the cable partway but that would be neater than what I'd intended.

Here's the end coming from the Maypole charger (not the car end) just to check I'm not going mad. It's the opposite of the diagram above.

Joesson · April 25, 2019, 20:06

Sorry if I am being the devil's advocate but your photo isn't definitive proof that there is something wrong. To be crystal clear you need to show each end of that cable, if then shown to be wrong it is not fit for purpose and you can take it from there with the supplier.

paulj · April 25, 2019, 20:31

Just been out to the car to have a look at my Maypole lead, should have done that earlier...

The lead connected to my battery also has the +ve as the bare pin when you take off the cap so I agree that Maypole appear to wire things backwards. Let the wire cutting commence!

Bossworld · April 25, 2019, 20:38

Quote from: Joesson on April 25, 2019, 20:06
Sorry if I am being the devil's advocate but your photo isn't definitive proof that there is something wrong. To be crystal clear you need to show each end of that cable, if then shown to be wrong it is not fit for purpose and you can take it from there with the supplier.

No offence taken. That picture is what's come out of the Maypole charger, so reasonably comfortable that red is positive and black is negative. The equivalent wiring harness manufactured by Maypole has the fuse on the red, positive terminal and charges the MR2 without issue.

The Maypole has:

Charger end:
Red covered
Black exposed

Harness end:
Red exposed
Black covered

The generic SAE cable, which matches the diagram above, is here:

It's a little difficult to see from the picture because the cable wants to go back to how it's been folded, but the positive/red cable with the fuse, has writing on the sleeve/jacket.

Harness end:
Red covered
Black exposed

This matches the diagram above. Makes me think Maypole have gone against the grain.

Bossworld · April 25, 2019, 20:39

Quote from: paulj on April 25, 2019, 20:31
Just been out to the car to have a look at my Maypole lead, should have done that earlier...

The lead connected to my battery also has the +ve as the bare pin when you take off the cap so I agree that Maypole appear to wire things backwards. Let the wire cutting commence!

Cheers

Joesson · April 25, 2019, 20:50

Remember, check twice cut once.