From what I've read it looks like thus us the one to go for. It says it's rated at 250A at 24V. Does this equate to 500A at 12V? OK for a buggy?

http://www.durite.co.uk/s/c/switches-and-indicators/battery-isolators/battery-isolator-250a-at-24v-and-2500a-54089

Looks fine to me - DURITE stuff is usually top quality too

Quote from: Dave DND on March 16, 2017, 09:33:02 AM
Looks fine to me - DURITE stuff is usually top quality too

Thanks Dave. Would you mount it on the dashboard or hide it somewhere?

Mine is on the bottom edge of the dashboard and i have the key on a string on the keyring with the other keys so i use both to start the car

Not exactly hidden but not obvious either

Quote from: Zip Buggy on March 16, 2017, 09:46:22 AM
Thanks Dave. Would you mount it on the dashboard or hide it somewhere?

That answer is dependent on whether is a safety or security feature   

Quote from: Doon L001 on March 16, 2017, 10:03:10 AM
Mine is on the bottom edge of the dashboard and i have the key on a string on the keyring with the other keys so i use both to start the car

Not exactly hidden but not obvious either

I like that idea. Think I'll do the same. Thanks Dave

Quote from: Dave DND on March 16, 2017, 10:06:59 AM

Quote from: Zip Buggy on March 16, 2017, 09:46:22 AM
Thanks Dave. Would you mount it on the dashboard or hide it somewhere?

That answer is dependent on whether is a safety or security feature   

I suppose it's mainly safety; competition cars usually have them somewhere really visible, for obvious reasons in the event of a wipe-out. Hopefully I won't be needing that! Having said that, security is something the buggy has precious little of. Every bit will help. I like Dave Doon's idea - think I'll go with that.

Quote from: Zip Buggy on March 15, 2017, 11:04:32 PM
From what I've read it looks like thus us the one to go for. It says it's rated at 250A at 24V. Does this equate to 500A at 12V? OK for a buggy?

http://www.durite.co.uk/s/c/switches-and-indicators/battery-isolators/battery-isolator-250a-at-24v-and-2500a-54089

[/

Hi Zip... Yes the theory is correct.  Allow a little leeway in practice. Keep the switch as close to the battery as you can. (Good practice for 12v systems). As a rule of thumb with any automotive wiring, the maximum theoretical voltage drop due to length of cable is 3%. The larger the cross section of the cable, in m\m2, the more the voltage drop in a given length.

(If you know the watts, not david that is  , of your load divide the watts by the voltage and this gives the amps). 

Can I preach a bit here... safety. Of all the issues I have come across on buggies over the years the number 1 has to be electrical failures. How many times have you heard "it worked when I put it away.. now it doesn`t"
Make sure the cable cross section in m\m2 is suitable for the load in amps. (Any supplier will have details on their website. Carbuilder solutions have several really good pages dedicated to wiring sizes. What you need for horns, lights etc).
In non- automotive wiring I solder joints every time. I have also on cars etc but this practice is frowned on by designers. There is a simple reason for this. If you solder a cable to a connector etc the theory is that, over time, the vibration & temperature changes cause a breakdown of the integrity of the soldered joint. This ups the joints resistance. This means the circuits draws more power. This heats the joint up more. This ups the resistance and so on. Another thing.... you cannot rely upon a fuse to prevent a fire. Won`t bore you further. I posted recently my one and only event in my first buggy. Fuse didn`t help me there. More up to date.... Zafira B fires.

So take care with wiring. Make sure the cable is not ancient. Make sure the connectors are securely fitted to the cable. Make sure all connections are clean. Use wet & dry to remove any verdigris from the connectors. Use correct connectors\connector blocks. Cover exposed copper wire at the connector to keep the crap out. Don`t use ancient switches. Do use relays.

Note out to frighten you off. Work carefully and to a plan with any wiring. Then you buggy will start every time. Will keep running. Wipers will work when you want them to. Indicators will flash properly. This alone has to be worth a bit of time and maybe a few bob here and there doesn`t it? 

Quote from: Paul1953 on March 16, 2017, 10:22:43 AM

Quote from: Zip Buggy on March 15, 2017, 11:04:32 PM
From what I've read it looks like thus us the one to go for. It says it's rated at 250A at 24V. Does this equate to 500A at 12V? OK for a buggy?

http://www.durite.co.uk/s/c/switches-and-indicators/battery-isolators/battery-isolator-250a-at-24v-and-2500a-54089

[/

Hi Zip... Yes the theory is correct.  Allow a little leeway in practice. Keep the switch as close to the battery as you can. (Good practice for 12v systems). As a rule of thumb with any automotive wiring, the maximum theoretical voltage drop due to length of cable is 3%. The larger the cross section of the cable, in m\m2, the more the voltage drop in a given length.

(If you know the watts, not david that is  , of your load divide the watts by the voltage and this gives the amps). 

Can I preach a bit here... safety. Of all the issues I have come across on buggies over the years the number 1 has to be electrical failures. How many times have you heard "it worked when I put it away.. now it doesn`t"
Make sure the cable cross section in m\m2 is suitable for the load in amps. (Any supplier will have details on their website. Carbuilder solutions have several really good pages dedicated to wiring sizes. What you need for horns, lights etc).
In non- automotive wiring I solder joints every time. I have also on cars etc but this practice is frowned on by designers. There is a simple reason for this. If you solder a cable to a connector etc the theory is that, over time, the vibration & temperature changes cause a breakdown of the integrity of the soldered joint. This ups the joints resistance. This means the circuits draws more power. This heats the joint up more. This ups the resistance and so on. Another thing.... you cannot rely upon a fuse to prevent a fire. Won`t bore you further. I posted recently my one and only event in my first buggy. Fuse didn`t help me there. More up to date.... Zafira B fires.

So take care with wiring. Make sure the cable is not ancient. Make sure the connectors are securely fitted to the cable. Make sure all connections are clean. Use wet & dry to remove any verdigris from the connectors. Use correct connectors\connector blocks. Cover exposed copper wire at the connector to keep the crap out. Don`t use ancient switches. Do use relays.

Note out to frighten you off. Work carefully and to a plan with any wiring. Then you buggy will start every time. Will keep running. Wipers will work when you want them to. Indicators will flash properly. This alone has to be worth a bit of time and maybe a few bob here and there doesn`t it? 

Hi Paul. Thank you for taking the time to write all that. All sound advice. My battery is mounted on the tunnel against the bulkhead so cable length to the cut-out switch will be minimal, thankfully.

Most of the wiring on my buggy is from the original 1974 loom but looks in good nick. I'm replacing bits of it when I move things around and adding relays etc. I'm using heatshrink connectors, unsoldered, (from AES) and also contralube to keep connections clean longterm, especially on old connectors that I've cleaned up. Chad has been giving me great advice on cable sizes when I'm adding new wiring. I admit my switches are the 1974 beetle ones so may need looking at - but all working fine currently - pun intended  .

I'm gradually building up my bespoke wiring diagram as I go along - adapted from one of Chad's excellent diagrams. I plan to include all wire colours and amp ratings.

Really appreciate the advice - this forum at it's best 

Sorry, just want to say as far as I know the greater the cross sectional area the lower the voltage drop, been a long time but I think I am right but will stand corrected

Quote from: Zip Buggy on March 16, 2017, 10:50:15 AM

Quote from: Paul1953 on March 16, 2017, 10:22:43 AM

Quote from: Zip Buggy on March 15, 2017, 11:04:32 PM
From what I've read it looks like thus us the one to go for. It says it's rated at 250A at 24V. Does this equate to 500A at 12V? OK for a buggy?

http://www.durite.co.uk/s/c/switches-and-indicators/battery-isolators/battery-isolator-250a-at-24v-and-2500a-54089

[/

Hi Zip... Yes the theory is correct.  Allow a little leeway in practice. Keep the switch as close to the battery as you can. (Good practice for 12v systems). As a rule of thumb with any automotive wiring, the maximum theoretical voltage drop due to length of cable is 3%. The larger the cross section of the cable, in m\m2, the more the voltage drop in a given length.

(If you know the watts, not david that is  , of your load divide the watts by the voltage and this gives the amps). 

Can I preach a bit here... safety. Of all the issues I have come across on buggies over the years the number 1 has to be electrical failures. How many times have you heard "it worked when I put it away.. now it doesn`t"
Make sure the cable cross section in m\m2 is suitable for the load in amps. (Any supplier will have details on their website. Carbuilder solutions have several really good pages dedicated to wiring sizes. What you need for horns, lights etc).
In non- automotive wiring I solder joints every time. I have also on cars etc but this practice is frowned on by designers. There is a simple reason for this. If you solder a cable to a connector etc the theory is that, over time, the vibration & temperature changes cause a breakdown of the integrity of the soldered joint. This ups the joints resistance. This means the circuits draws more power. This heats the joint up more. This ups the resistance and so on. Another thing.... you cannot rely upon a fuse to prevent a fire. Won`t bore you further. I posted recently my one and only event in my first buggy. Fuse didn`t help me there. More up to date.... Zafira B fires.

So take care with wiring. Make sure the cable is not ancient. Make sure the connectors are securely fitted to the cable. Make sure all connections are clean. Use wet & dry to remove any verdigris from the connectors. Use correct connectors\connector blocks. Cover exposed copper wire at the connector to keep the crap out. Don`t use ancient switches. Do use relays.

Note out to frighten you off. Work carefully and to a plan with any wiring. Then you buggy will start every time. Will keep running. Wipers will work when you want them to. Indicators will flash properly. This alone has to be worth a bit of time and maybe a few bob here and there doesn`t it? 

Hi Paul. Thank you for taking the time to write all that. All sound advice. My battery is mounted on the tunnel against the bulkhead so cable length to the cut-out switch will be minimal, thankfully.

Most of the wiring on my buggy is from the original 1974 loom but looks in good nick. I'm replacing bits of it when I move things around and adding relays etc. I'm using heatshrink connectors, unsoldered, (from AES) and also contralube to keep connections clean longterm, especially on old connectors that I've cleaned up. Chad has been giving me great advice on cable sizes when I'm adding new wiring. I admit my switches are the 1974 beetle ones so may need looking at - but all working fine currently - pun intended  .

I'm gradually building up my bespoke wiring diagram as I go along - adapted from one of Chad's excellent diagrams. I plan to include all wire colours and amp ratings.

Really appreciate the advice - this forum at it's best 

A pleasure... You and Chad have it covered.   I have just stripped my donor beetle loom and the wiring is in fact in surprisingly good condition except where it has been chopped and messed about with. AES is my number one choice also.

Quote from: Gary on March 16, 2017, 09:14:47 PM
Sorry, just want to say as far as I know the greater the cross sectional area the lower the voltage drop, been a long time but I think I am right but will stand corrected

Hi Gary.... You have me thinking now.  Will have to re-visit my schooldays physics lessons again. Started secondary school in 1964. We all had to learn Ohms & Boyles laws. By gum if you got it wrong out came the ruler and a whack across the knuckles followed. Very different now eh... 

Yep... I stand corrected. Gary has this the right way round.. Greater the cross sectional area the less resistance.. Bit like the bigger the door the more people can run through at the same time. 

Quote from: Paul1953 on March 17, 2017, 09:23:57 AM


Yep... I stand corrected. Gary has this the right way round.. Greater the cross sectional area the less resistance.. Bit like the bigger the door the more people can run through at the same time. 

Thank you Gary and Paul. That's really good to know. I actually bought 5 metres of 50amp Brown wire for earths the other day from my local caravan supplies shop - it was the only decent thickness brown wire they had. I won't be shy about using it now

I don't suppose anyone has a diagram on how to wire in one of these? Or any advice as on which wires off the ignition switch is needed as a security precaution I have an idea I think its the red wire off the back of the switch I've also heard about the coil positive mines going in a battery box just above the starter.

Stupid question just might as well do it whilst I'm re wiring the whole thing.