I'll have 2- #2 awg cables from the MS 60 MPPT CC to the 4-220a batteries, then I'll have 2-4/0 cables from the batteries to the Mag 2012 inverter, plus the other cables/wiring as needed for the solar system etc.I'll be wiring the batteries as the #3 way example shows in the smart battery site for balanced loading.How or what would be the best way to securely attach all these cables/wires to the batteries?It appears that it is or might get kinda crowded in the battery box, withall these large cables etc.Tia,Don

Any auto parts store carries battery post clamps with screw clamps for cables of generous proportions.

Hi,Method #3 uses wires to a buss. Connect all the other wires to the buss.

Don is right - Smartgauge method #3 requires 2 busses separate from battery bank. Use method #2, it's good enough. You can put up to 4(?) cable lugs on one Pos battery terminal. So you have 1 from MPPT, 1 from inverter, 1 from trailer load, 3 total. Plus, much thinner wires from MPPT volt sense and temp sensor if you have it. I don't see a problem.If you need more than 3 cables on one terminal, you can install a terminal extension (or whatever it's called) - a lug that is bolted to the terminal and lets you put more wires on it. To avoid crowding, use as short interconnect cables as needed. This shop will make you custom length of any cable, with quality lugs and shrink tubes installed. Very low labor surcharge - I think I paid $2 per cable, on top of cable and parts cost. Their parts are local but inexpensive, cheaper and better than Amazon cr-ap.

Hi,It is best practise to use method #3 or #4.

I like all my 12V connections to use NEW heavy cables with ring terminal crimped on. I also like to use quality terminal blocks and stud connections like you see in the BLUE SEA catalogs.. I usually order all my cables from ANCOR and make my own cables. All of my connections are to a terminal block or a stud somewhere using ring terminals. makes for easy removal and trouble shooting.Also great for matching up cables for equalizing current flow etc...I use one of those 8-ton hand crimpers and follow quality cable making procedures trying to keep everything new for the initial install.This makes all the cables neat in appearance as well as great performance.I use heat shrink adhesive tubing ends to keep moisture down around the crimp portion of the cables. If I really want to make things look very professional I can also add heat shrink cable markers before hand crimping the ends....It sort of comes natural for me as this is what I did for a living way back then running the DOD electronics systems road trips... Like the old saying goes "they don't say hanes until I say hanes"... Of course some guys just lay them on a concrete slab and smack them with a hammer.Roy Ken

How to securely connect?? | Good Sam Community

17 Replies

BoonHauler
Explorer
May 22, 2014
nvreloader wrote:
Guys IIRR,
Both MS and Mag 2012 OEM spec's say to connect to the neg post of the battery, for the sensors wiring etc.

Don,
The battery bank will be 4-6v GC batteries from Costco, untll I understand and Know how to run this solar setup,+ I'll have the 2 Deep cycle tongue batteries as back up.

Tia,
Don H

The temp sensors go on the/a negetive terminal, that's true for both Morningstar and Magnum equipment.

As for balancing the battery bank IMHO I believe it should be done and method #2 would work for you but think of your two 6V batteries in series a one 12V battery as shown in the SmartGuage drawing.
RoyB
Explorer II
May 21, 2014
NVRELOADER - The blue thing is a ANCOR Heat gun. I use a regular HEAT GUN from LOWES that has the clip on heat attachments

The cable marker I have comes from my work days and is a high dollar KROY CABLE MARKER K5100. Looks like this and you have to buy the heat shrink tubing that it writes on. Looks great when you are done. They make cheaper label makers on the market. The heat shrink type are the best for cables - just slide them over the wire and use heat gun to shrink them in place.

The idea of making your own cables really turns out nice... They all use the ring terminals so easy on-easy off... Note the ends of the cables that are outside or connects to the battery terminals all have adhesive type tubing in place to prevent moisture from getting into your crimp area.

Roy Ken
pianotuna
Nomad III
May 21, 2014
Hi,

One of the quick ways to early battery death is too high a temperature. About 50 C (122 f) is the upper safe limit. The gassing voltage is only 13.2 at that temperature. When charging if that is reached the charging needs to be stopped, or at least limited severely.
Almot
Explorer III
May 21, 2014
pianotuna wrote:
Actually the negative post is hotter than the positive. So that is why it is used for the temperature sensor on the Blue Sky, so it can accurately reflect the temperature inside the battery.

Ok. But it doesn't matter which Neg post. This doesn't affect the balancing in any way. If you do have to connect temp sensor to Neg, then it can be any Neg.

But I'm curious, why over-stating the temperature is better than the other way around? Why taking either extreme is better, to begin with?
pianotuna
Nomad III
May 21, 2014
Hi Don H,

Then treat them as two large 12 volts and use method #2. It can not be improved on.

nvreloader wrote:

Don,
The battery bank will be 4-6v GC batteries from Costco, untll I understand and Know how to run this solar setup,+ I'll have the 2 Deep cycle tongue batteries as back up.

Tia,
Don H
pianotuna
Nomad III
May 21, 2014
Hi Almot,

Actually the negative post is hotter than the positive. So that is why it is used for the temperature sensor on the Blue Sky, so it can accurately reflect the temperature inside the battery.

There are other sensor designs that are intended to be placed on the side of a battery.
Almot
Explorer III
May 21, 2014
Don... If temperature sensor is not insulated, it "could" matter whether you attach it to Pos or Neg terminal. But it doesn't matter to which one Pos or Neg.

In my controller temp sensor is insulated, and can be mounted on anything, as long as this "anything" is the closest to the averaged temperature of all the batteries in the bank.
nvreloader
Explorer
May 18, 2014
Guys IIRR,
Both MS and Mag 2012 OEM spec's say to connect to the neg post of the battery, for the sensors wiring etc.

Don,
The battery bank will be 4-6v GC batteries from Costco, untll I understand and Know how to run this solar setup,+ I'll have the 2 Deep cycle tongue batteries as back up.

Tia,
Don H
pianotuna
Nomad III
May 18, 2014
Hi Almot,

It actually does matter. For example Blue Sky asks that the temperature sensor be connected to a negative terminal.

It is best practise to use balanced wiring.

Almot wrote:
Temp sensor will read most correctly if attached to the terminal also. Again, doesn't matter to what terminal.
Almot
Explorer III
May 18, 2014
I wonder how many people here believe in balancing :)... And how many believe in it so much that have to use method #3 or 4. Few are using method #2 though.

Voltage sense wires should be connected as close to the bank as possible, therefore - directly to the terminal is better than to the buss. Doesn't matter to what pair of terminals.

Temp sensor will read most correctly if attached to the terminal also. Again, doesn't matter to what terminal.

Btw, check photos of Roy's battery box. Pretty smart arrangement, with switches right there inside, on the box ledge. He posted plenty of OEM pics today but didn't post his work pics, and I forgot where I saw them here.