One for the Auto Electricians..

[BigRAWesty]

I am installing the dual battery system and would like to know if I can run my accessories fuse bank off the aux side of the solenoid as I don't really want to run a wire back to the battery for both. Seems a bit pointless running main to battery then the same back to the fuse bank...
I can't see an issue but was wondering if any damage could be done when it turns on to either solenoid or accessories.??
Cheers
http://www.nissanpatrol.com.au/forums/images/imported/2013/02/101.jpg
http://www.nissanpatrol.com.au/forums/images/imported/2013/02/102.jpg

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[macca]

Thats what I would do, keeps it tidy by the location of the solonoid and the fuse block.

[BigRAWesty]

Thats what I would do, keeps it tidy by the location of the solonoid and the fuse block.

Yep, spot on. I can't see it being an issue as you have it connected to the same terminal weather its at the battery or solenoid.

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[mcleod]

Cant see it being an issue either. Only comment would be that as I understand solenoids, the main battery is the charging priority. If you run things off the second battery need to make sure the solenoid will provide charge to it at some stage.

[BigRAWesty]

Cant see it being an issue either. Only comment would be that as I understand solenoids, the main battery is the charging priority. If you run things off the second battery need to make sure the solenoid will provide charge to it at some stage.

Yea, to build a little on your question, I have the 90A alternator. So seeing as I'm not going to be using 90a worth in my accessories it should still charge the battery. That's my understanding.

My main worry is a spike or surge being so close to the solenoid.

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[the evil twin]

I think I get what you mean... you want any gear connected to that fuse panel to be powered from your Aux battery... if so then absolutely no Probs doing that at all, Westy

[Yendor]

Yes you can connect your fuse box to the solenoid that's not a problem.

I don't recommend mounting the fuse box or solenoid on the firewall in that position. Just above it is the outlet for the water from the plenum chamber and I think where you have it mounted they will get covered in water every time it rains.

To check, run some hose water in the vents at the bottom of the windscreen with the bonnet up and see if the water goes over them.

[BigRAWesty]

Yes you can connect your fuse box to the solenoid that's not a problem.

I don't recommend mounting the fuse box or solenoid on the firewall in that position. Just above it is the outlet for the water from the plenum chamber and I think where you have it mounted they will get covered in water every time it rains.

To check, run some hose water in the vents at the bottom of the windscreen with the bonnet up and see if the water goes over them.

Hmmmmm good thought... Will inspect tomorrow..

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[BigRAWesty]

Yes you can connect your fuse box to the solenoid that's not a problem.

I don't recommend mounting the fuse box or solenoid on the firewall in that position. Just above it is the outlet for the water from the plenum chamber and I think where you have it mounted they will get covered in water every time it rains.

To check, run some hose water in the vents at the bottom of the windscreen with the bonnet up and see if the water goes over them.

Well I grabbed a fee 9 ltr buckets and threw them over the car.. water seems to stay away from the solenoid but was just touching fuse bank. So I moved the bank further behind the solenoid.
Thanks for the pick up, didn't think of it myself..

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[BigRAWesty]

Ok, another quick question...
Need to fit a cig plug to the rear of our ford but budget is tight. Would it be fine to run just a positive 6mm positive to the rear and body earth the negative? Or is that asking to much?
I ask as I can get the single 6mm for free (work) but will need to buy the 2 core.
So will it be ok?

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[Ben-e-boy]

Ok, another quick question...
Need to fit a cig plug to the rear of our ford but budget is tight. Would it be fine to run just a positive 6mm positive to the rear and body earth the negative? Or is that asking to much?
I ask as I can get the single 6mm for free (work) but will need to buy the 2 core.
So will it be ok?

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

you could IF you do a continuity check between the point you want to use as the earth and the battery earth to prove it you could get away with it. But slim chance getting a good earth through the body panels

[Bob]

Just run two of your single 6mm cables. (one for Earth and one for Positive). Would have to label though

[rottodiver]

Westy, I "body earth" pretty much everything at the back end of the car.... Have not had a problem with any wiring of anything ever!!

[BearGUST]

Westy, I "body earth" pretty much everything at the back end of the car.... Have not had a problem with any wiring of anything ever!!

Same here, no drama's.

[BigRAWesty]

If I body earth, can damage be done to my fridge? Or will it just not run correctly if not a solid earth?

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[rottodiver]

I run an 80 litre engel and it has been in there for at least 5 years without a problem, again the earth is through the body

[Yendor]

I wouldn't earth it to the body.

Your not paying for the cable, do as Bob has suggested.

[rottodiver]

Yendor, out of interest for my sake why would you not earth it to the body?? Is this a bad thing??
Scotty

[Yendor]

Yendor, out of interest for my sake why would you not earth it to the body?? Is this a bad thing??
Scotty

They make bad earths for numerous reasons......paint, body sealant, quality of metal used.....etc.

In an electrical circuit the same amount of current flows in the positive side as the negative side.

Having an inadequate earth is similar to using a to smaller wire size for the positive.

[rottodiver]

How do I know if it is a bad earth?? Is there a tell tale sign ?

[mcleod]

I wouldn't do it either. Like bob said if you can get single core just use two of them. If you are relying on the body earth you are effectively adding potential resistance into the circuit via the extra connections. If one of them goes bad you could open circuit your power supply or make it useless due to the higher resistance. While ever the earth connection is good (i.e you can measure the same resistance through the earth connection to the negative terminal as a direct cable to the negative) you shouldn't have any issues, as that connection goes bad things will start to play up. Nothing beats a direct connection.

[Dominator]

A bad earth will cause voltage drop, or a in layman's terms a loss of voltage ie. instead of 12.4v you might only have 11.4v. Less voltage = higher current (I=V/R) So your fridge will chew more current (Amps) from your battery.

While a direct connection is good I have run 6mm to the back of my patrol for my fridge +tve and use the body as an earth. I just scraped the paint away where I connected the earth to the body. Under full load of the fridge I have less than .05v of drop. That to me is acceptable.

On a side note have a look in the engine bay where the negative cable runs from the battery to the body. You will find there is paint under the terminal. Take the bolt out and scrape some paint off then reattach the terminal.

[Yendor]

The Patrols don't use the body as the main earth. There is an earth wire in the harness that links numerous body locations in the engine bay, in the cab, behind the dash and at the rear of the vehicle, it also connects to the alternator housing. The alternator housing is earth to the engine and the engine is connected to the negative battery post by the heavy battery cable.

This is the main earth circuit. Yes it is possible that some current may also earth through the body.

So when you install an accessory at the rear of the vehicle and earth it to the body you are actually connecting it to the earth wire in the original harness.

The problem with this is that electrical engineers when designing the circuits use the smallest size wire possible to keep cost down. In places this wire is only 3 or 4mm.

The best practice when installing electrical items in the rear (or heavy drawing items) is to also run an earth cable.

rottodiver, The best way to check an earth is to measure voltage drop from that earth body point to the negative battery post with all the accessories running that use that earth circuit. Such as lights, rear demister, rear wiper, fridge and what ever else you might have.

[rottodiver]

Ok next question...... I fully understand what you are saying yendor( and thanks) but being that I have a triple battery( only recently triple but always had a dual system) and being that a lot of us have at least a dual battery system I would bet most people have earthed their second or third to the engine block or body( my second is earthed to the block and my 3rd to the body), so would your last explanation still apply... I have 13.6 volts at my engel and and my sockets at the rear, do you think I should move these earths to battery( which I could easily do now I am running 3 batteries)
Scotty

[Yendor]

Was that reading taken with everything running?

I advise that an earth lead be run to the rear.

With your 3rd battery are you using a DC-DC charger or?

[BigRAWesty]

So going with dominator, if you have good voltage all should be right

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

[rottodiver]

No yendor not running dc to dc charger.... I spoke to quite a few people about this and because I am using 2 identical agm batteries and they are so easily charged of the alternator it won't be a problem so I have them wired in parallel.

The battery voltage I mentioned was without the car running, with the car running it sits on about 14.2 v but I does go down to 13.9 while driving on 40 plus degree days!!!

[rottodiver]

The problem with this topic is so many different opinions on here, on the Internet, ringing auto electricians...... Very hard to find any literature on it........ Although I do appreciate hearing reasons for and against......

[rottodiver]

Westy....... Right now I have my arms up in the air looking confused..... Things have run well for me for a hell of a lot of years but am I putting strain on my electrical system........I don't know!!!!!! Maybe I will be spending some time rewiring....... Lol
Scotty

[Yendor]

No yendor not running dc to dc charger.... I spoke to quite a few people about this and because I am using 2 identical agm batteries and they are so easily charged of the alternator it won't be a problem so I have them wired in parallel.

The battery voltage I mentioned was without the car running, with the car running it sits on about 14.2 v but I does go down to 13.9 while driving on 40 plus degree days!!!

That's the problem with opinions everyone has one. :D

I originally posted to Kallen's question about wiring up a fridge in a Ford. I responded with the best method so he could get maximum benefit out of his fridge.

Your 3 battery system is totally different to Kallen's fridge (except for the earthing to the body).

To be honest the voltage readings you have stated across your third battery surprises me. I noticed in another thread you have cooked your second battery within a couple of days. Are you sure this was from exhaust heat? Have you checked the voltage across the second battery with the engine running at a fast idle with no electrical load, to make sure it's not being overcharged?.

I would never fit a gel deep cycle battery under the bonnet nor would I charge it without some sort of smart charger.

Yes the above is my opinion based on my training and experience. Other people will have different opinions.

It's your vehicle, it's up to you how things are done.

[rottodiver]

Yep cooked the battery in 2 days... It swelled up at the end right next to my extractors and was red hot........ Do you think it is something different, ( i would imagine if it was from any voltage issues i may have seen it in the other one which is identical) as for under the bonnet, I asked the question from the 12v home and they assured me no problems although as I said I have noticed the drop in voltage with a very hot engine bay (viscous fan had to be replaced on Friday as it was not working and we have had high 30,s low 40 degree days.(engine temp exceeding 100 degrees) As me bing well aware of my voltages I have an abr volt meter on my dash and also and ecu of which are consistent, and then I have another volt meter at the back of the car ( the press button type one with a 12v power supply), I have been conscious of them because of the swelling of the battery and to be honest I am quite surprised there was no real effect from the swelling but how long for, I don't know so I will be changing it out as my new one arrived.
One more thing, you are surprised at the voltages, do you think they should be more or less?
Also I appreciate your knowledge and I am considering changing a few things because of it!!!!!

[Dominator]

The Patrols don't use the body as the main earth.

The earth on my '96 GQ patrol goes from the negative terminal on my start battery to the body then to the engine block. As far as I can tell it looks like the factory wiring. I would take a photo but my folks have my patrol at the moment.

As for your fridge, 90% of people will run their fridge off their 2nd battery and almost all people will have their 2nd battery negative run to the body. So like I said earlier, while running both positive and negative from your battery to your fridge (or any other accessory) is the best option, in most cases connecting the negative from your fridge/accessory to the body will suffice.

If you are concerned you can test voltage drop simply by turning your fridge or accessory on, and using a multimeter test the voltage directly at your battery and then test the voltage at your accessory socket. Any difference in voltage = your voltage drop.

[Yendor]

Yep cooked the battery in 2 days... It swelled up at the end right next to my extractors and was red hot........ Do you think it is something different, ( i would imagine if it was from any voltage issues i may have seen it in the other one which is identical) as for under the bonnet, I asked the question from the 12v home and they assured me no problems although as I said I have noticed the drop in voltage with a very hot engine bay (viscous fan had to be replaced on Friday as it was not working and we have had high 30,s low 40 degree days.(engine temp exceeding 100 degrees) As me bing well aware of my voltages I have an abr volt meter on my dash and also and ecu of which are consistent, and then I have another volt meter at the back of the car ( the press button type one with a 12v power supply), I have been conscious of them because of the swelling of the battery and to be honest I am quite surprised there was no real effect from the swelling but how long for, I don't know so I will be changing it out as my new one arrived.
One more thing, you are surprised at the voltages, do you think they should be more or less?
Also I appreciate your knowledge and I am considering changing a few things because of it!!!!!

I was surprised that the voltage at the 3rd battery was that high.

Once you get the new battery in check the charge rate across the second battery with a known good voltmeter, with the engine at a fast idle with all electrical items switched off where possible.

[rottodiver]

Will do that.... I do have a good automotive multimeter!!! Picking the car up Monday after work so will do it then........watch this space!!!
Scotty

[Yendor]

The earth on my '96 GQ patrol goes from the negative terminal on my start battery to the body then to the engine block. As far as I can tell it looks like the factory wiring. I would take a photo but my folks have my patrol at the moment.

As for your fridge, 90% of people will run their fridge off their 2nd battery and almost all people will have their 2nd battery negative run to the body. So like I said earlier, while running both positive and negative from your battery to your fridge (or any other accessory) is the best option, in most cases connecting the negative from your fridge/accessory to the body will suffice.

If you are concerned you can test voltage drop simply by turning your fridge or accessory on, and using a multimeter test the voltage directly at your battery and then test the voltage at your accessory socket. Any difference in voltage = your voltage drop.

Yes the negative battery lead connects onto the inner guard below the battery.

As explained in the post you took the snip from this is not the main earth for the rear of the vehicle.

I don't know how you got the 90% figure but that doesn't mean it's the best way of doing it.

As I said above, it's your vehicle do with it what you please.

[Clunk]

I know its nothing to do with patrols but have just bought a new battery for the missus scooter and unbeknownst to me, it doesnt come pre-filled with electrolyte, let alone come charged.
So my question is......... Is it ok to fill cells with plain distilled water or should it be mixed with sulfuric acid first?


Don't slap it, tap it!!!!

[NP99]

The seller should have done that for you.

[Alitis007]

I know its nothing to do with patrols but have just bought a new battery for the missus scooter and unbeknownst to me, it doesnt come pre-filled with electrolyte, let alone come charged.
So my question is......... Is it ok to fill cells with plain distilled water or should it be mixed with sulfuric acid first?


Don't slap it, tap it!!!!

Distilled water should be fine i would think, then see if it has enough charge to start the scooter. It should be fine coz some manufacturers ship batteries dry to save on the weight and for safety.

[Clunk]

The seller should have done that for you.


Distilled water should be fine i would think, then see if it has enough charge to start the scooter. It should be fine coz some manufacturers ship batteries dry to save on the weight and for safety.

Cheers guys, just took it back to where I got it from and they filled it up for me. Should self charge over a few hours, so will see how it goes.

Don't slap it, tap it!!!!

[Clunk]

Well battery works fine, stupid scooter won't fire up been over 8 months since last ridden, so will need to strip all the GUrly bits off to get to all the necessaries..... too dark now so goin down the bottlo instead.

Don't slap it, tap it!!!!

[NP99]

Well battery works fine, stupid scooter won't fire up been over 8 months since last ridden, so will need to strip all the GUrly bits off to get to all the necessaries..... too dark now so goin down the bottlo instead.

Don't slap it, tap it!!!!

Use some fresh fuel and a can of start you bastard......