help needed for charge controllers

[Hayder]

Hi there,

I am from Pakistan. I have a little technical question related to connecting charge controllers in series.

Currently I have 2 charge controllers. one is of 48V and other is of 12/24V. I want to know is it possible to connect these controllers in series to get 72v charge controller?

And if no, can I connect three cheap charge controllers of 12/24v in series to get 72v charge controller?

If both of situations are not possible, then what cheap solution is possible to cut battery charging when batteries are full?

Thanks in Advance

[Wy_White_Wolf]

No

No

The only real solution is to get a charge controller made for 72v charging. There are a few available in the comercial/industrial market but most likely you'll have to have one custom built.

WWW

[terrapin8]

Sounds like you need a DC to DC converter to get it upto 72v.

Hi there,

I am from Pakistan. I have a little technical question related to connecting charge controllers in series.

Currently I have 2 charge controllers. one is of 48V and other is of 12/24V. I want to know is it possible to connect these controllers in series to get 72v charge controller?

And if no, can I connect three cheap charge controllers of 12/24v in series to get 72v charge controller?

If both of situations are not possible, then what cheap solution is possible to cut battery charging when batteries are full?

Thanks in Advance

[Mike90250]

The Midnight Classic line of charge controllers, has a 72V battery programming. It can go up to 90VDC for batteries if 72v is not enough!

http://www.midnitesolar.com/documents.php?productCat_ID=21&productCatName=Charge%20Controllers%20-%20Classics&model=CLASSIC%20150&product_ID=256&act=products

A DC-DC convertor will not charge a 72V battery, which needs about 87V to fully charge

[Hayder]

I am sorry I didn't explain my objective very clearly.
Actually I have 1600 watt solar installed on my home. Originally it was 12v system i.e. with single battery and a 12v UPS (Inverter).
After few months I shifted it to 24v system i.e. solar system with 2 batteries and a 24v UPS (Inverter).
Charge controller used in both of above cases was 12/24v auto detect. A simple PWM charge conroller.

This year I shifted it to 48v system i.e. system with 4 batteries and a 48v (1500Kva) UPS. I purchased used Tarom 48v Charge controller.

But now I am interested to expand my solar system so that it could be capable enough to power my whole electric system in day time.
I am interested to purchase a used MGE 3200 Pulsar EXtreme Inverter from market. its almost free i.e in just PKR 15000/- (US $15)
It operates on 6 batteries. I will purchase 6 new Lead-acid batteries and modify this inverter to use these batteries.

but unfortunately there is no 72v charge controller available in market. So i need to do something.
I need no high tech charge controller. I just need a controller that can cut battery charging when batteries are full. ( I know importance of MPPT, but I am very well aware of my pocket as well )

Since I have one 24v and one 48v charge controller, so i read some where that two charge controllers can be used in series.

Hope you will understand my problem and will help me.

thanks

No

No

The only real solution is to get a charge controller made for 72v charging. There are a few available in the comercial/industrial market but most likely you'll have to have one custom built.

WWW

Sounds like you need a DC to DC converter to get it upto 72v.

The Midnight Classic line of charge controllers, has a 72V battery programming. It can go up to 90VDC for batteries if 72v is not enough!

http://www.midnitesolar.com/documents.php?productCat_ID=21&productCatName=Charge%20Controllers%20-%20Classics&model=CLASSIC%20150&product_ID=256&act=products

A DC-DC convertor will not charge a 72V battery, which needs about 87V to fully charge

[josephrussel]

Best Alternative

Hi Hayder,

After going through your actual issue which you have mentioned recently so I will suggest you that you have to need compromise with your "pocket" otherwise you have one more option that you can go to online and can get 72v charger controller as per your requirement. Please have a look to mentioned link in which you can find the charger which you need for your solar heating system.

http://www.alibaba.com/showroom/charge-controller-72v.html