Cheapo remote battery isolator
Cheapo remote battery isolator
Author
Discussion

donkmeister

Original Poster:

12,975 posts

130 months

Saturday 5th February 2022
quotequote all
Mrs D's dad has a collection of Citroen Picassos. Yes, I know.

He doesn't get out in them as much as is really necessary to keep them in good order. Battery replacement is becoming a burden, so I'd like to fit isolators so he can shut off the battery each time he uses it.

I've used simply ones that mount on the terminal before, but the problem here is the battery is under the passenger seat so it's a non starter. What we need is a switch or pull cord tucked out of the way inside each car.

I've found the cartech isolators that have a remote switch, but £200-300 each isn't going to get his approval. The cars are parked in the shade so solar panel is a non starter, and as he's elderly he believes anything left plugged into the mains will explode and take out his house, so no battery tenders. Yes it's a PITA.

Any thoughts or recommendations on a remote isolator that is a cheap solution?

Scrump

23,947 posts

188 months

Saturday 5th February 2022
quotequote all
Extend the negative battery cable to an accessible location (maybe just at the base of the seat) and fit the cheap isolator there.

GreenV8S

31,024 posts

314 months

Saturday 5th February 2022
quotequote all
The maintainer would be the best solution although it would involve plugging the car in every time it was used which gets tedious. Up to you whether you think you can win that debate. Otherwise I'd go for an automatic isolator. These will isolate and connect the battery as necessary without the driver having to remember. The cost of a good automatic isolator isn't much in the context of annual ownership costs especially if the alternative is having a flat battery every time you want to use the car and throwing batteries away at regular intervals.

Worth checking that the insurance is OK with cars being left with flat batteries or isolated batteries since that would disable any alarm. That's probably your most compelling argument in favor of battery maintainers.

tapkaJohnD

2,000 posts

234 months

Saturday 5th February 2022
quotequote all
donkmeister,

Every car involved in motorsport must have an isolator, by sporting regulations. They are widely available, look like this and cost about £10:



Other versions are available at greater cost, with extra contacts to make using it safe to use while the engine is running, and I note one that's even cheaper and lower profile: https://sinolec.co.uk/en/battery-isolator-switches...

They are fitted in the main cable from the battery to the vehicle's loom. In a competition vehicle, they are mounted externally and in an obvious position so that marshals may use them in an incident, but could be mounted internally and unobtrusively.

Good luck,
John

donkmeister

Original Poster:

12,975 posts

130 months

Saturday 5th February 2022
quotequote all
Thanks all, looks like a manual isolator mounted to the floor by the seat will be the solution.

tapkaJohnD thanks for the link; I see they do one with a mounting box (rather than bulkhead mount) so I'll have a think if I can run the existing negative lead far enough out of the way to avoid having to extend it whilst avoiding the risk of seat chaffing. Time to get out the big crimper! biggrin

Polly Grigora

11,209 posts

139 months

Saturday 5th February 2022
quotequote all
Got to laugh at the Chinese stuff and how current ratings are all messed up and even change during the journey to Europesmile

Here https://jenny2000china.en.made-in-china.com/produc...

ratings are shown as



then something strange happens and the outcome is



Now it's reached the UK and the fun starts proper



You couldn't make it upsmilesmilesmile

finishing touch

818 posts

197 months

Sunday 6th February 2022
quotequote all
tapkaJohnD said:
donkmeister,

Every car involved in motorsport must have an isolator, by sporting regulations. They are widely available, look like this and cost about £10:



Other versions are available at greater cost, with extra contacts to make using it safe to use while the engine is running, and I note one that's even cheaper and lower profile: https://sinolec.co.uk/en/battery-isolator-switches...

They are fitted in the main cable from the battery to the vehicle's loom. In a competition vehicle, they are mounted externally and in an obvious position so that marshals may use them in an incident, but could be mounted internally and unobtrusively.

Good luck,
John
I have one of these fitted to my negative earth wire in my (open top) Seven for use at shows.
Apparently, Mums & Dads think it perfectly OK for their offspring to play with all the switches. I've seen them stand and watch.
At least if I leave the car unattended I can take the key with me and not come back to a flat battery.

Paul G


Edited by finishing touch on Sunday 6th February 10:43

finlo

4,453 posts

233 months

Sunday 6th February 2022
quotequote all
You can get isolators that automatically disconnect if the voltage drops for not much money like the one pictured (don't know how to do links).

tapkaJohnD

2,000 posts

234 months

Sunday 6th February 2022
quotequote all
Polly Grigora said:
Got to laugh at the Chinese stuff and how current ratings are all messed up and even change during the journey to Europesmile

Here https://jenny2000china.en.made-in-china.com/produc...

ratings are shown as



then something strange happens and the outcome is



Now it's reached the UK and the fun starts proper



You couldn't make it upsmilesmilesmile
Polly,
I'm no advocate for Chinese made kit, I've bought some rubbish, but I note that the company I linked to has two different low-profile cut-off switches, at different prices, the higher amperage being the more expensive. Sinolec has a name that suggests specialising in Chinese kit, and a Purchasing Director with a Chinese name, but it's perfectly possible to make identical-looking items with different specs. The products you cite may have been designed and built to safely carry the current they are advertised to do.
John

Turn7

25,739 posts

251 months

Sunday 6th February 2022
quotequote all
This is what I use on the Caterham, cost about a tennner for the disconnect and a longer earth lead.


Polly Grigora

11,209 posts

139 months

Sunday 6th February 2022
quotequote all
Turn7 said:
This is what I use on the Caterham, cost about a tennner for the disconnect and a longer earth lead.

Nice job, better than much of the rubbish on the market

What's confusing me is that the OP wants to disconnect the batteries to prevent them from going flat over long periods

Leaving batteries stood in a filled state and inactive is going to cause a problem

There's also no logic in using a master switch to disconnect the main battery cable when wanting to prevent a few milliamp current drain

A low current rated dash mounted toggle switch might be all that's needed to isolate a stereo system or control unit, once what's drawing a few milliamp has been proven

Turn7

25,739 posts

251 months

Sunday 6th February 2022
quotequote all
Polly Grigora said:
Turn7 said:
This is what I use on the Caterham, cost about a tennner for the disconnect and a longer earth lead.

Nice job, better than much of the rubbish on the market

What's confusing me is that the OP wants to disconnect the batteries to prevent them from going flat over long periods

Leaving batteries stood in a filled state and inactive is going to cause a problem

There's also no logic in using a master switch to disconnect the main battery cable when wanting to prevent a few milliamp current drain

A low current rated dash mounted toggle switch might be all that's needed to isolate a stereo system or control unit, once what's drawing a few milliamp has been proven
Yes, thats possible, but if the issue is simiar to Caterhams, it is the factory fit Immobiliser that is the parastic drain, so this is the easiest option to prevent that.


Polly Grigora said:
Nice job, better than much of the rubbish on the market
thumbup

monthou

5,390 posts

80 months

Sunday 6th February 2022
quotequote all
Polly Grigora said:
Leaving batteries stood in a filled state and inactive is going to cause a problem
It is?

Polly Grigora

11,209 posts

139 months

Sunday 6th February 2022
quotequote all
monthou said:
Polly Grigora said:
Leaving batteries stood in a filled state and inactive is going to cause a problem
It is?
Yes, in the past slowly charging and discharging the stored batteries was a method used by some

No idea about battery technology/manufacture over recent years, wouldn't surprise me if improvements had been made

The thing is, 10 minutes ago did some studying and apparently temperature plays a big part, wasn't aware of the temp factor, also the OP's dad in law would have to leave the vehicles unused for a long time for there to be a problem

In summary - The above statement is meaningless without more info

Polly Grigora

11,209 posts

139 months

Sunday 6th February 2022
quotequote all
Turn7 said:
Polly Grigora said:
Turn7 said:
This is what I use on the Caterham, cost about a tennner for the disconnect and a longer earth lead.

Nice job, better than much of the rubbish on the market

What's confusing me is that the OP wants to disconnect the batteries to prevent them from going flat over long periods

Leaving batteries stood in a filled state and inactive is going to cause a problem

There's also no logic in using a master switch to disconnect the main battery cable when wanting to prevent a few milliamp current drain

A low current rated dash mounted toggle switch might be all that's needed to isolate a stereo system or control unit, once what's drawing a few milliamp has been proven
Yes, thats possible, but if the issue is simiar to Caterhams, it is the factory fit Immobiliser that is the parastic drain, so this is the easiest option to prevent that.


Polly Grigora said:
Nice job, better than much of the rubbish on the market
thumbup
How do they work, have seen pics of them in the past but never looked at one closely

Do they have a spring that splits the terminals? Guessing though

Turn7

25,739 posts

251 months

Sunday 6th February 2022
quotequote all
Polly Grigora said:
Turn7 said:
Polly Grigora said:
Turn7 said:
This is what I use on the Caterham, cost about a tennner for the disconnect and a longer earth lead.

Nice job, better than much of the rubbish on the market

What's confusing me is that the OP wants to disconnect the batteries to prevent them from going flat over long periods

Leaving batteries stood in a filled state and inactive is going to cause a problem

There's also no logic in using a master switch to disconnect the main battery cable when wanting to prevent a few milliamp current drain

A low current rated dash mounted toggle switch might be all that's needed to isolate a stereo system or control unit, once what's drawing a few milliamp has been proven
Yes, thats possible, but if the issue is simiar to Caterhams, it is the factory fit Immobiliser that is the parastic drain, so this is the easiest option to prevent that.


Polly Grigora said:
Nice job, better than much of the rubbish on the market
thumbup
How do they work, have seen pics of them in the past but never looked at one closely

Do they have a spring that splits the terminals? Guessing though
No spring, just a weird plastic inbetween the 2 halfs, that I guess allows current to flow when crushed.

donkmeister

Original Poster:

12,975 posts

130 months

Sunday 6th February 2022
quotequote all
Turn7 said:
Polly Grigora said:
Nice job, better than much of the rubbish on the market

What's confusing me is that the OP wants to disconnect the batteries to prevent them from going flat over long periods

Leaving batteries stood in a filled state and inactive is going to cause a problem

There's also no logic in using a master switch to disconnect the main battery cable when wanting to prevent a few milliamp current drain

A low current rated dash mounted toggle switch might be all that's needed to isolate a stereo system or control unit, once what's drawing a few milliamp has been proven
Yes, thats possible, but if the issue is simiar to Caterhams, it is the factory fit Immobiliser that is the parastic drain, so this is the easiest option to prevent that.
Basically this.

I love Citroens, but they are far from the gold standard that electronic engineers aspire to biggrin

The head-unit has been omitted on 2 of them (this was actually creating a drain). I could spend some time and effort trying to track down the culprits however I suspect it is the security system. Easiest thing is to isolate the battery.

This will:
1) avoid the battery being drained by uncontrollable parasitic losses
2) avoid the battery being drained if he's left the courtesy light on by mistake
3) avoid the bulk of the conversations where I have to listen to the monologue entitled "why can't cars be like years ago when you could leave them for a decade with the battery connected and they still turned over. Also people only ate normal food that doesn't have garlic in it, and asbestos was still good for you back then.".

Sorry, a small insight into my personal life there.

Polly Grigora

11,209 posts

139 months

Sunday 6th February 2022
quotequote all
donkmeister said:
Turn7 said:
Polly Grigora said:
Nice job, better than much of the rubbish on the market

What's confusing me is that the OP wants to disconnect the batteries to prevent them from going flat over long periods

Leaving batteries stood in a filled state and inactive is going to cause a problem

There's also no logic in using a master switch to disconnect the main battery cable when wanting to prevent a few milliamp current drain

A low current rated dash mounted toggle switch might be all that's needed to isolate a stereo system or control unit, once what's drawing a few milliamp has been proven
Yes, thats possible, but if the issue is simiar to Caterhams, it is the factory fit Immobiliser that is the parastic drain, so this is the easiest option to prevent that.
Basically this.

I love Citroens, but they are far from the gold standard that electronic engineers aspire to biggrin

The head-unit has been omitted on 2 of them (this was actually creating a drain). I could spend some time and effort trying to track down the culprits however I suspect it is the security system. Easiest thing is to isolate the battery.

This will:
1) avoid the battery being drained by uncontrollable parasitic losses
2) avoid the battery being drained if he's left the courtesy light on by mistake
3) avoid the bulk of the conversations where I have to listen to the monologue entitled "why can't cars be like years ago when you could leave them for a decade with the battery connected and they still turned over. Also people only ate normal food that doesn't have garlic in it, and asbestos was still good for you back then.".

Sorry, a small insight into my personal life there.
Understood, fit, wire and forget about current drains from anything now or arising in the future

Probably for the best

That switch that Turn7 has used is a great idea, so simple and very cheap, it's close to working like magic


GreenV8S

31,024 posts

314 months

Sunday 6th February 2022
quotequote all
Most of the motorsport battery isolators will be designed with a removable key. In your application I assume you'd want one with a non-removable key. If they exist, they aren't common.

Lucas make (or used to make) a switch which looks quite different to an FIA battery isolator but does a similar job. There was another company - I think it was 'Longacre' or something like that - who offer a switch which has a fixed handle which is styled similar to the standard FIA switch.

paintman

7,860 posts

220 months

Sunday 6th February 2022
quotequote all
GreenV8S said:
Most of the motorsport battery isolators will be designed with a removable key. In your application I assume you'd want one with a non-removable key. If they exist, they aren't common.

{b]Lucas make (or used to make) a switch which looks quite different to an FIA battery isolator but does a similar job[/b]. There was another company - I think it was 'Longacre' or something like that - who offer a switch which has a fixed handle which is styled similar to the standard FIA switch.
Are you thinking of this one?:
www.autoelectricsupplies.co.uk/product/142/categor...

Few more here from the above:
https://www.autoelectricsupplies.co.uk/product_lis...

Lots of battery isolators in marine use.
https://boatelectricals.co.uk/battery-switches/