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snewin
4th November 2012, 02:29 PM
Got these cheapies off eBay and going to put 2 in the dash for main & 2nd battery, and one in the rear for 2nd battery.

21976

Red is to power the unit +ve anywhere from 4 to 30v
Black is earth or -ve.
Yellow is the +vs lead in from the voltage you want to test.

I've tested them 9v & 1.5v batteries and the seem to work alright, although you can't combine the red & yellow wires, you need 2 separate +ve sources, I should have bought the 2-wire gauge for that, d'oh.

My plan is to keep it simple. For the two in the dash run a wire each from the positives of both batteries and split them both into 2.

I'll power the gauge for the main battery with the 2nd battery & vice versa and then read off the other split and just run a common earth.

For the rear ill power off the +ve for the rear interior light and read voltage off the accessory cable to the rear.

Is it really that simple or have I overlooked something?

MudRunnerTD
4th November 2012, 02:35 PM
That seems a little Odd?

Are you sure the Yellow is not the Back Light wire for dash lights? Its only a monitor digital display so needs very little to run and i would have thought it would power up from the supply it is measuring, ie. 4V to 30V.??

It seems pointless that you have to supply a second control circuit?

I assume that is a Single row Digital display?

Can you post an eBay link to this item so i can have a look at the add mate.

Cheers MR

harro959
4th November 2012, 02:37 PM
That sounds like it should work. I am planning on doing something similar in 2 weeks.

Except i am only using one gauge, a 1/32 din sized volt meter from jaycar that has 1 +ve input and 1 -ve input (i think it was $8). I am then hooking it up to a 3 way switch.
Position 1 - main batt
position 2 - off
position 3 - auxillary

I am mounting it in a aluminium panel that im going to use to replace the cluster of 3 switches to the right hand side of the steering wheel, above the fuse block.

In the end it will be nearly identical to the abr sidewinder battery monitor, only lots cheaper. :)

snewin
4th November 2012, 02:51 PM
Here is the item number 110899866942

I thought it was a bit odd too Mudrunner but no, its correct afaik.

I'm 99% sure it'll work just making sure I didn't leave anything out.

Thanks Harro, I got three mounting options in order of preference...

21978

21979

21980

harro959
4th November 2012, 05:06 PM
No problems. I like the option of under the sub tank switch. Its really the only place where you can safely keep an eye on them if you are worried about something.

Here is the link for the abr one i have copied for mine.

http://www.ebay.com.au/itm/DUAL-BATTERY-SYSTEM-MONITOR-12V-VOLT-METER-ABR-NEW-/390491325277?pt=AU_Car_Parts_Accessories&hash=item5aeb18c35d&_uhb=1#ht_2492wt_1203

This is where im putting mine when i get the chance to do it properly. Only out of aluminium instead of plastic.

Just trying to give you more options :). I am considering changing now though because i like the under the sub tank switch idea too....

megatexture
4th November 2012, 05:48 PM
You can get a baintec dual volt meter that sits flush mounted or in a little pod an you dont have to switch between batts to view them and mine was cheeper than the sidewinder unit

boots
4th November 2012, 06:00 PM
Heres a pic of mine and has three wires , but as Mudrunner said one was for the backlight . Have mine going through a three way toggle switch to check either battery .

Lieney
4th November 2012, 06:37 PM
That sounds like it should work. I am planning on doing something similar in 2 weeks.

Except i am only using one gauge, a 1/32 din sized volt meter from jaycar that has 1 +ve input and 1 -ve input (i think it was $8). I am then hooking it up to a 3 way switch.
Position 1 - main batt
position 2 - off
position 3 - auxillary

I am mounting it in a aluminium panel that im going to use to replace the cluster of 3 switches to the right hand side of the steering wheel, above the fuse block.

In the end it will be nearly identical to the abr sidewinder battery monitor, only lots cheaper. :)
I agree with the others in that yellow might be a back-light. Is there a switch on the unit?
If not the that would be my assumtpion.,
You could use a 2 position, 3 pole switch. One battery to an end terminal, other battery to the other. Middle terminal would go to the power side of the unit (red wire).
Earth to an accessories / ignition activated relay so it''s on when accessoried is on

threedogs
4th November 2012, 06:50 PM
I have two but dont know which I'll use yet,both very simple.
plus very cheap, voltage is in the ball park,

snewin
4th November 2012, 06:56 PM
After the testing I've done theres no back light. If you combine the red & yellow wires it reads zero voltage.

Once separated to different inputs it seems to work. I'm pretty sure it'll be ok.

There's no switch on the unit. One unit per battery. See both at the same time. Each powered by the other battery. Too easy.

Harro - I got a power window and fog light control under there. How do you think you'd get behind the panek? If you do it take some photos for me.

Boots - those spottie mounts were perfect. Sorry I couldn't stay, I was still drunk and we had a 12 hour drive in front of us. Your beer will be on its way soon ;)

snewin
4th November 2012, 06:58 PM
I liked the look of those ciggie plug ones 3d but I wanted something flush mount and not using my sockets. I want to start to get away from wires everywhere

threedogs
4th November 2012, 07:08 PM
Only $5 , hey works for me, put can see if volts are going over the top easy. That other one I;ll hard wire somewhere and mount in under dash or on centre console

boots
4th November 2012, 08:00 PM
No problem at all bud .
After the testing I've done theres no back light. If you combine the red & yellow wires it reads zero voltage.

Once separated to different inputs it seems to work. I'm pretty sure it'll be ok.

There's no switch on the unit. One unit per battery. See both at the same time. Each powered by the other battery. Too easy.

Harro - I got a power window and fog light control under there. How do you think you'd get behind the panek? If you do it take some photos for me.

Boots - those spottie mounts were perfect. Sorry I couldn't stay, I was still drunk and we had a 12 hour drive in front of us. Your beer will be on its way soon ;)

snewin
4th November 2012, 08:00 PM
Good thing about those ciggie plug ones too is that you could put it on an extension cable and sit in camp and have it right there instead of trudging back to the fourby to check it.

harro959
5th November 2012, 07:57 AM
Harro - I got a power window and fog light control under there. How do you think you'd get behind the panek? If you do it take some photos for me.



Admittedly i havnt spent too much time looking at it. Im guessing something along the lines of me head down bum up in the foot well trying to figure it out :)

Will post a few pics when i actually get it done.