twin battery trickle charge question

[747sp]

this is the batery tray from my Atlantic 75 Ex rescue service Rib. i have posted here before when it had 4 batteries - i have now reduced it to two. The wiring is fundementally the same - instead of four negaives being tied together, its now two. Each anderson plug feeds a port or starboard engine circuit. If you are in anyway interested you can see a photo on an ipad at the bottom of my thumbnail showing the original RNLI 4 battery tray. So my question is - with my negatives tied together - if i wanted to put a trickle charger on these batteries - can i use two chargers wired with anderson plugs and simply plug them in to the two circuits you see here. im guessing it should work as when the engines are running the "altenators" are effectively doing exactly the same thing...?

[A1an]

Why are the negatives linked together?

[Pikey Dave]

Originally Posted by A1an

Why are the negatives linked together?

They should be[emoji106]

[A1an]

Originally Posted by Pikey Dave

They should be[emoji106]

Apologies, I read it as feeding an engine each.

[beamishken]

Why use 2 chargers ? If its just to keep the batteries topped up then you could link the two positives & just use 1 charger.
No different to the way they were charging when you had 4 batteries in use
Obviously you would remove the link before plugging back into the engines

[Limecc]

This is the correct way to connect two batteries

[GuyC]

He has two separate circuits, one for each engine. It all ends up at a common negative so linking them at the battery is fine.

For me and if you have two chargers I'd disconnect the negative link between the two batteries and then plug the chargers into the Anderson connectors.

I think it would be fine to leave the batteries connected but I'm never sure what the impact is on the smart bit of the charger, assuming your trickle charger is a smart charger.

[Pikey Dave]

Originally Posted by GuyC

He has two separate circuits, one for each engine. It all ends up at a common negative so linking them at the battery is fine.

For me and if you have two chargers I'd disconnect the negative link between the two batteries and then plug the chargers into the Anderson connectors.

I think it would be fine to leave the batteries connected but I'm never sure what the impact is on the smart bit of the charger, assuming your trickle charger is a smart charger.

I have a double battery setup & leave the batteries “combined” when I connect the charger when she’s laid up. I use a Ctek xs7000, no issues.

[GuyC]

Originally Posted by Pikey Dave

I have a double battery setup & leave the batteries “combined” when I connect the charger when she’s laid up. I use a Ctek xs7000, no issues.

Cheers Dave

OP - Yes is the answer.

[Last Tango]

Originally Posted by Pikey Dave

I have a double battery setup & leave the batteries “combined” when I connect the charger when she’s laid up. I use a Ctek xs7000, no issues.

+1

Current drops back to about 60mA once they're charged up (2 X 75AH).

The digital ammeter is handy, lets you know if you've left something switched on. eg.

https://www.ebay.co.uk/itm/DC-0-100V....c100005.m1851

[747sp]

Thanks all - i think i will disconect the combined negative as i dont need it on the set up out of the boat. i have ordered two of the same Ctex xs 7 Chargers. I have some old copper pipe that fits nicely inside the anderson connectors and will solder in well. i can flatten one end of it, drill a hole and use some nuts and bolts to connect to the spade endings on the cabling from the chargers. i just need to remember to reinstall the tied negative before next season. thanks again.

[Pikey Dave]

Originally Posted by 747sp

Thanks all - i think i will disconect the combined negative as i dont need it on the set up out of the boat. i have ordered two of the same Ctex xs 7 Chargers. I have some old copper pipe that fits nicely inside the anderson connectors and will solder in well. i can flatten one end of it, drill a hole and use some nuts and bolts to connect to the spade endings on the cabling from the chargers. i just need to remember to reinstall the tied negative before next season. thanks again.

Why bother faffing, the cteks come with crocodile clips. Just put them straight to the battery posts.

[747sp]

You are right... but I do love a faff. It is an area beyond the long arm of home compliance...

[Pikey Dave]

Originally Posted by 747sp

You are right... but I do love a faff. It is an area beyond the long arm of home compliance...

I know what you mean, I’m in the middle of a major faff meself[emoji849]

[jeffstevens763@g]

Tow bar rack gone out the window Dave?

[Pikey Dave]

Originally Posted by jeffstevens763@g

Tow bar rack gone out the window Dave?

Yup, there’s no way would it all have fitted in[emoji849]

[GuyC]

Originally Posted by 747sp

Thanks all - i think i will disconect the combined negative as i dont need it on the set up out of the boat. i have ordered two of the same Ctex xs 7 Chargers. I have some old copper pipe that fits nicely inside the anderson connectors and will solder in well. i can flatten one end of it, drill a hole and use some nuts and bolts to connect to the spade endings on the cabling from the chargers. i just need to remember to reinstall the tied negative before next season. thanks again.

That is just the type of over engineered solution that I subscribe to.

[GuyC]

Originally Posted by Pikey Dave

Yup, there’s no way would it all have fitted in[emoji849]

Thread hi-jack but is that some sort of sliding engine bed?

[Pikey Dave]

Originally Posted by GuyC

Thread hi-jack but is that some sort of sliding engine bed?

Yup a rolling floor.