Magnum Interter/Charger

boowho · 05-24-2013, 05:23 PM

On the control panel for this unit there are three lights, labeled Bulk, Absorb and Float.

From what I can tell, these represent several levels or charging rate. Bulk being the highest rate and float the lowest.

The float on mine is always illuminated, indicating to me (at least) that my bats are always being charged.

Could this be the reason that my bats are out-gassing, releasing acid and generally causing a mess in the compartment most of the time?

I asked Magnum support about this in an email, but they were pretty much no help at all. I also asked them which terminal (on the attached diagram) the temperature sensor should go on and no help there either.

Herk? Anyone?

Boowho??

garbonz · 05-24-2013, 06:13 PM

Need to check the voltages when the bats are on float. Depending on the type of battery (flooded, gel or AGM) the float voltage should be around 13.3 to 13.7 volts. If its higher than that, your batteries are being fried and you need a new charges. The temperature sensor is only important during the bulk and absorption stages, as these periods are very dependent on temperature.

Himcules · 05-24-2013, 06:32 PM

temp sensor goes on the negative post on the far top right (same place as where the negative cable of the charger is connected). as garbonz mentioned, it's more critical during the heavier charging stages.

float is the trickle charge state. since your batteries are constantly being used by all the misc little devices inside, it'll constantly sip at the batteries and the magnum charger will know this so it keeps trickling in more juice...

where is the temp sensor now? my factory stock install was in the wrong location. as were the rest of my cables. it's wired to work, but was not correct. one "12v" (set of 6v batteries) were more heavily charged/drained by the magnum inverter than the other set. after changing the positive cable, my house 12v system now drains evenly across the bank. i need to measure and order the correct set of cables to fix this so i don't overuse and abuse the batteries.

**Herk7769** · 05-24-2013, 06:37 PM

Boowho's appears to be correctly wired to me.

boowho · 05-24-2013, 07:38 PM

Quote:

Originally Posted by Himcules

temp sensor goes on the negative post on the far top right (same place as where the negative cable of the charger is connected)

OK, to be clear...... Which neg post? I assume either 1 or 2??

So based upon the responses, it appears that the float light will always be on as long as juice is being consumed by 12v devices in the coach.

I've had the charger disabled for a couple of days and the bats are staying clean. I will check the voltages to see if they are in the range mentioned by garbonz.

One reason I think FR may mis-wire the bats is that the posts on the bats I have are extremely short to have 3 different cables attached. The nut doesn't even go all the way on.

By mis-wiring, the max number of cables attached to any post is 2, so the nut goes on properly..... my guess is that the installer just takes the easy way out.

Boowho??

garbonz · 05-24-2013, 07:51 PM

Quote:

Originally Posted by boowho

OK, to be clear...... Which neg post? I assume either 1 or 2??

So based upon the responses, it appears that the float light will always be on as long as juice is being consumed by 12v devices in the coach.

I've had the charger disabled for a couple of days and the bats are staying clean. I will check the voltages to see if they are in the range mentioned by garbonz.

Boowho??

For the temp sensor, it don't matter which negative pole you use in your properly wire system, each will see the same temperatures.

You will need to hook up the charger again and let it go to float to see if it is overcharging.. If you are seeing signs of gassing ( not including the Mexican dinner last night), then that is a pretty clear sign that the charger is over charging at float IMO.

Himcules · 05-24-2013, 10:26 PM

per page 16 of the installation manual:
negative wire AND temp sensor are on the same post at the FIRST battery in the string. positive wire on the positive post of the LAST battery in the string.

so if your berkshire is like mine and the inverter is in the bay to the right of your diagram, then from the MM1212 inverter, you connect to post #2 BOTH the negative line and the battery sensor. on the positive post of where you have #3, is where your positive connection needs to be (not to the post you labeled as #3).

Quote:

Originally Posted by boowho

...
One reason I think FR may mis-wire the bats is that the posts on the bats I have are extremely short to have 3 different cables attached. The nut doesn't even go all the way on.

By mis-wiring, the max number of cables attached to any post is 2, so the nut goes on properly..... my guess is that the installer just takes the easy way out.

Boowho??

you can get 3 on the same post if you remove the washer, but it is a tight fit. i had to do that to change my wiring to correct it.

i don't think the installer was taking the easy way out, i think he misunderstood how battery systems work and tried to wire in a clean and short matter. it took effort to wire the batteries in my coach, just was the wrong way to do it..

JBoyer · 05-25-2013, 08:46 AM

Boowho,

Certainly lots of great advice above - many very knowledgable folks that have saved my bacon several times. The battery issue you're experiencing finally drove me to swap Magnum controllers. I had new batteries installed at purchase and they were getting thrashed - and the slide was becoming a total mess. I swapped out the original Magnum controller with the one pictured below - which allows you to set the charge rate. I set it lower and have not had an issue since. The batteries take slightly longer to charge but you can input many of these parameters and then let the controller do its thing.

klucas · 05-25-2013, 10:08 AM

I have been watching this thread as I have corrosion problems also. I like the idea of the control panel upgrade. Where can I find that? Part number? And easy install?? I agree if I can change the rate of charge that should fix this problem.

boowho · 05-25-2013, 10:17 AM

Quote:

Originally Posted by Himcules

per page 16 of the installation manual:
negative wire AND temp sensor are on the same post at the FIRST battery in the string. positive wire on the positive post of the LAST battery in the string.

so if your berkshire is like mine and the inverter is in the bay to the right of your diagram, then from the MM1212 inverter, you connect to post #2 BOTH the negative line and the battery sensor. on the positive post of where you have #3, is where your positive connection needs to be (not to the post you labeled as #3).

you can get 3 on the same post if you remove the washer, but it is a tight fit. i had to do that to change my wiring to correct it.

i don't think the installer was taking the easy way out, i think he misunderstood how battery systems work and tried to wire in a clean and short matter. it took effort to wire the batteries in my coach, just was the wrong way to do it..

Getting more confused...... I obviously have the high amp wires (the green ones in my diagram). I have the temperature sensor. Finally I have a very light gauge wire (actually two wires bundled together) that is black. This is all the wires I have. I don't know what this "light gauge" black wire is for, but I'm going to put it and the temp sensor on post 2 of my diagram.

Thanks Himc.....

Boowho??

boowho · 05-25-2013, 10:20 AM

Quote:

Originally Posted by klucas

I have been watching this thread as I have corrosion problems also. I like the idea of the control panel upgrade. Where can I find that? Part number? And easy install?? I agree if I can change the rate of charge that should fix this problem.

Me too.... The part number is mentioned in the manual. They are on EBay for about $125 to $140. JBoyer, is it plug compatible with the current panel, or do you have to run extra wiring??

Boowho??

Himcules · 05-25-2013, 10:47 AM

Quote:

Originally Posted by boowho

Getting more confused...... I obviously have the high amp wires (the green ones in my diagram). I have the temperature sensor. Finally I have a very light gauge wire (actually two wires bundled together) that is black. This is all the wires I have. I don't know what this "light gauge" black wire is for, but I'm going to put it and the temp sensor on post 2 of my diagram.

Thanks Himc.....

Boowho??

in my rig, the lighter gauge wires are for the 12v house side.(some appliance somewhere i'm not sure, could be slide motors, fridge propane controller, fans, i'm not sure as nothing is labeled).

theoretically, the best set up is to treat the bank as it was only one battery with 2 posts only. you ignore all the interconnecting posts and use only the 2 main posts: negative of #2 and positive of the battery that has #3 for everything.

you do have the challenge of making everything fit on the posts as they are not tall enough to hold all the lugs. FR should have included post extensions and longer wires.

so in simplest terms, the best wiring setup by the book, is to use only the negative #2 post for all black cables. all red positive cables go to the positive post of where you have #3 negative labeled). that means to move your green lines in your diagram but you will need to get lug post extensions to make all the lugs fit (or something similar).

Himcules · 05-25-2013, 11:02 AM

Quote:

Originally Posted by boowho

Me too.... The part number is mentioned in the manual. They are on EBay for about $125 to $140. JBoyer, is it plug compatible with the current panel, or do you have to run extra wiring??

Boowho??

according to the installation manual for both remote displays: MM-RC (stock remote we have with the 6 LEDs) and the ME-ARC (advance remote control), they both use a standard telephone cable to connect to the inverter. so it is just a simple swap, plug and play for connectivity...

JBoyer · 05-25-2013, 01:16 PM

It was plug and play! I enlarged the opening on the cabinet face to flush mount, but otherwise, a 5 minute job. I don't have the model # in front of me, but there are two versions. I got the middle one - the high-end will do some extra things like generator remote start. I have had NO issues of any kind since installing. I could not be happier for the money.

boowho · 05-25-2013, 01:20 PM

Quote:

Originally Posted by JBoyer

It was plug and play! I enlarged the opening on the cabinet face to flush mount, but otherwise, a 5 minute job. I don't have the model # in front of me, but there are two versions. I got the middle one - the high-end will do some extra things like generator remote start. I have had NO issues of any kind since installing. I could not be happier for the money.

I'm ordering mine today!!

Boowho??

klucas · 05-30-2013, 03:42 PM

Quote:

Originally Posted by JBoyer

Boowho,

Certainly lots of great advice above - many very knowledgable folks that have saved my bacon several times. The battery issue you're experiencing finally drove me to swap Magnum controllers. I had new batteries installed at purchase and they were getting thrashed - and the slide was becoming a total mess. I swapped out the original Magnum controller with the one pictured below - which allows you to set the charge rate. I set it lower and have not had an issue since. The batteries take slightly longer to charge but you can input many of these parameters and then let the controller do its thing.

I got my upgraded control box today in the mail. I want to install it this weekend. What was the charge rate you set it up for? I would assume the current control box is max charge so maybe 50 % would stop the leaking?

tmmar · 05-30-2013, 03:50 PM

How do you change the charge rate with the control panel? I have that panel in my coach and didn't know that the charge rate could be changed.

Himcules · 05-30-2013, 03:55 PM

Quote:

Originally Posted by tmmar

How do you change the charge rate with the control panel? I have that panel in my coach and didn't know that the charge rate could be changed.

press setup and then use the dial knob to rotate through the options. press the dial knob in to select the item.

controls of the ME-RC and MM-ARC are similar...

https://www.youtube.com/watch?v=8jVFw-wRh_4

Quote:

Originally Posted by klucas

I got my upgraded control box today in the mail. I want to install it this weekend. What was the charge rate you set it up for? I would assume the current control box is max charge so maybe 50 % would stop the leaking?

make sure you have the battery type setup correctly. that sets the charge curve. i think default is at 80%, not 100%. so changing it lower is safer and slower...

tmmar · 05-30-2013, 04:11 PM

So as long as the battery type is set up correctly, then the charge curve is automatically set? Is this correct?

Himcules · 05-30-2013, 04:17 PM

Quote:

Originally Posted by tmmar

So as long as the battery type is set up correctly, then the charge curve is automatically set? Is this correct?

that is what the manual claims... i would try just seeing how that affects the temps on the batteries first. if it's still too much, then lower the charge percentage...

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