Yes, if you put the sense wire on the output side of the isolator you would have the correct voltage there. The only problem is it only reads the one battery. If you have a high load on that batt and no load on the other, the batt with no load gets over charged. So many ways to do this and they all have a little downfall. Could do twin alternators.
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Dual battery questions.
- Thread starter 85 Jimmy
- Start date
Not sure it would......
I will have to think about it some more. Been up a while, tired and my leg is hurting, so I may be a little fuzzy.
My thinking right now is this:
The .7 volts dropped across a silicon PN junction, is not a resistance, but the turn-on voltage, and is not a function of the load.
A diode would have some resistance, of course, everything not superconducting has some, but the wires would probably have more.
If the output of the alternator was 15.2 volts, 14.5 + .7, and was applied to the anodes of two identical diodes, then the output of each should be the same.
A heavy load on the sense side, would draw the voltage of the whole system down due to alternator capacity and wire resistance.
Thus the non-sense side would see the same voltage as the sense side.
A heavy load on the non-sense side would also draw down the voltage. The sense side would try to boost the voltage to compensate.
However, the only voltage difference between the two batteries would be due to the voltage drop in the wire from the non-sense diode to the battery to non-sense battery.
Any voltage drop in the main charging wire, or the alternator would be sensed and compensated for because it would be shared by both batteries.
Or so it seems right now. It may look different in the morning.......
I will have to think about it some more. Been up a while, tired and my leg is hurting, so I may be a little fuzzy.
My thinking right now is this:
The .7 volts dropped across a silicon PN junction, is not a resistance, but the turn-on voltage, and is not a function of the load.
A diode would have some resistance, of course, everything not superconducting has some, but the wires would probably have more.
If the output of the alternator was 15.2 volts, 14.5 + .7, and was applied to the anodes of two identical diodes, then the output of each should be the same.
A heavy load on the sense side, would draw the voltage of the whole system down due to alternator capacity and wire resistance.
Thus the non-sense side would see the same voltage as the sense side.
A heavy load on the non-sense side would also draw down the voltage. The sense side would try to boost the voltage to compensate.
However, the only voltage difference between the two batteries would be due to the voltage drop in the wire from the non-sense diode to the battery to non-sense battery.
Any voltage drop in the main charging wire, or the alternator would be sensed and compensated for because it would be shared by both batteries.
Or so it seems right now. It may look different in the morning.......
Nice! So it's not that you don't have the clutter, you just hid it inside a box. Good idea.
creative cleaning... 
You may be right on that one Fordum. I haven't really sat down and looked at it too close so I have no argument on that one. I know our electrical engineers don't use them anymore as we were having problems with house batteries boiling the water out from overcharge. That's all I have to go on right now. ACRs are an awesome system as long as you don't overload them with starting loads. The problem is they aren't too cheap yet.
composite fiberglass.. machine extruded under 50,000 psi.. comes in 4 x 8 sheets..
here, i'll find pics.. smoked plexi cover...
here, i'll find pics.. smoked plexi cover...
Like I said, I ran mine for 10 years. I did have a boil out problem early on. I jumped a fellow off with the "sense" battery.
It did not have remote sensing, but it was the one that the original system was hooked to, so it was the one the alternator saw.
I had the engine running when I jumped him off, and the alternator output going into the heavy load of the dead battery blew that diode, so the alternator did not see any load afterwards.
Since the other battery was still hooked thorough the good diode, it was getting whatever the alternator output rose to.
After a couple of miles, I noticed that my voltmeter was not showing a charge. I stopped and checked. Found the other battery bubbling.
I grabbed a heavy piece of wire, and tied the two output terminals of the isolator together.
When I got home, I took the isolator apart, and replaced the internal diodes with some rated at about 3 times the current.
If I remember, that gave me a rating of about 150 amps per diode. I also bolted a large thick piece of aluminum to the fender and then put the isolator heat sink on it.
Never had any more problems after that.
I kept meaning to add a second voltmeter to monitor the other battery, but never did
Every time I opened the hood and had a meter handy, I compared the voltages and they were always within a .1 volt or less.
But that was usually with two fully charged batteries.
It did not have remote sensing, but it was the one that the original system was hooked to, so it was the one the alternator saw.
I had the engine running when I jumped him off, and the alternator output going into the heavy load of the dead battery blew that diode, so the alternator did not see any load afterwards.
Since the other battery was still hooked thorough the good diode, it was getting whatever the alternator output rose to.
After a couple of miles, I noticed that my voltmeter was not showing a charge. I stopped and checked. Found the other battery bubbling.
I grabbed a heavy piece of wire, and tied the two output terminals of the isolator together.
When I got home, I took the isolator apart, and replaced the internal diodes with some rated at about 3 times the current.
If I remember, that gave me a rating of about 150 amps per diode. I also bolted a large thick piece of aluminum to the fender and then put the isolator heat sink on it.
Never had any more problems after that.
I kept meaning to add a second voltmeter to monitor the other battery, but never did
Every time I opened the hood and had a meter handy, I compared the voltages and they were always within a .1 volt or less.
But that was usually with two fully charged batteries.
I don't think I've ever seen anyone with a problem in a 4x4, pick-up/camper or anything but a couple boats that had house batt problems. They are a good system and work fine. I tend to nit-pic **** too much.
Oops, I forgot and typed a bad word. Sorry.
Oops, I forgot and typed a bad word. Sorry.
basically yeah.. any thickened resin/glue works.. the glass behaves just like standard glass. grind, cloth, fill, etc..
the most economical is just thickening up regular polyester resin with cabosil or the like..... slather up the joints.. clamp it all in place.. wipe excess..
that building technique of using the angle pieces in the corners, is a technique I developed yr's ago for building tackle stations, etc on the boats...
it's an amazing product.. impervious to weather.. period.. you can let those raw pieces sit in the weather for 20 yrs and nothing will happen.. no fade, cracking, etc..
not particularly cheap... a 4 x 8 of 1/4" thick is like $250.. been awhile since I bought any.. but pound for pound, stronger than steel..
it's been used thruout my K5 build..
that box.
windstar shroud
dash bezel
8 panels in my center and overhead console
breaker panel in glovebox
custom heater
rear tool wall
interior qrter panels..
the most economical is just thickening up regular polyester resin with cabosil or the like..... slather up the joints.. clamp it all in place.. wipe excess..
that building technique of using the angle pieces in the corners, is a technique I developed yr's ago for building tackle stations, etc on the boats...
it's an amazing product.. impervious to weather.. period.. you can let those raw pieces sit in the weather for 20 yrs and nothing will happen.. no fade, cracking, etc..
not particularly cheap... a 4 x 8 of 1/4" thick is like $250.. been awhile since I bought any.. but pound for pound, stronger than steel..
it's been used thruout my K5 build..
that box.
windstar shroud
dash bezel
8 panels in my center and overhead console
breaker panel in glovebox
custom heater
rear tool wall
interior qrter panels..
I like the idea of it. We build everything out of aluminum. I have that stuff running out of my ears!! So all my boxes and stuff are alum. For insulated stuff like that we use Seaboard. Not bad stuff but doesn't like to glue together.
right.. starboard type stuff... basically like cutting board material...
I'm still fixing boats from Sandy..
anyway, plenty of good multi battery ideas/parts from the marine biz... certainly broadened my knowledge WAY beyond what I thought I knew as a hotrod builder..
I'm still fixing boats from Sandy..
anyway, plenty of good multi battery ideas/parts from the marine biz... certainly broadened my knowledge WAY beyond what I thought I knew as a hotrod builder..
Yes that's exactly the switch. I always have it in 1+2 unless I have it in OFF.
Didn't answer your other questions. One battery comes in each side on top. All the outputs come off the bottom: starter, winch, cooling fan, and that's also where the charge wire from the alternator is connected. The studs on the back are big enough to accommodate all that. In the near future I'll set up my CUCV bus bar to tie in all the loads. Makes it a little easier to add loads/connections to the output.
As you can gather from the discussion, the big disadvantage to my system is that a problem in one battery will affect the other. I do like the simplicity and having both batteries sharing the winch load especially considering it could draw over 500A.
As you can gather from the discussion, the big disadvantage to my system is that a problem in one battery will affect the other. I do like the simplicity and having both batteries sharing the winch load especially considering it could draw over 500A.
