Battery Lead Acid as Backup!

[PAC8911]

Hi!

I want to buy a charger for a lead acid battery of 12V and 7.5Ah. The charger must be connected to a power supply of 24V and I already have options. My problem is that I want to use the battery as backup connect to a circuit that needs 12V and 0.2A. I was thinking in connecting in parallel the charger, with the battery and my circuit but I don't know if this is possible.

I have read in some places and they say that the charger must think that the battery needs more energy and change from "maintenance mode to charging mode" and this would cause a overcharging. Is this right? I mean is just 0.2A? is there any solution?

Later I want to know if after the light comes back and the charger start charging the battery will send 2A, this would affect in some way my device?

I was thinking is use the Model 2544 of Mascot.co as charger.
The battery is a Ritar 1275 of 12V and 7.5ah.
I will connect some sensors and a Rabbit Board (both can work from a range of 9V to 18, so there is no problem with the 14.7V of the charger)

Thanks!

 

[ftcnet]

see post # 3 at 12v 7ah (ups battery charger)
It should do what you need.

 

[PAC8911]

Well is not exactly what I was looking because I really want to buy it. But thanks! My question is about connecting a charger and a device in parallel and use the charger as power supply. What happen if they are connected in parallel and the charger is in the first step providing 2A. ¿How can i be sure that my device just take .2A and the others 1.8A goes to the battery? Because if not my circuit would be burn!

 

[ftcnet]

Well is not exactly what I was looking because I really want to buy it.

This is a electronic design forum. You can easily purchase battery chargers at auto parts stores.
But thanks! My question is about connecting a charger and a device in parallel and use the charger as power supply.

My answer says go ahead and do just that.
What happen if they are connected in parallel and the charger is in the first step providing 2A. ¿How can i be sure that my device just take .2A and the others 1.8A goes to the battery? Because if not my circuit would be burn!

You should review the concepts involved in understanding Ohms law and DC circuits. The amount of current that a device will allow through it determined by it's resistance and the voltage accross it. You've already mentioned that the 14.7V charging voltage is not a problem for the devices that will be connected.

see: Understanding Ohms law for further explanation

 

[PAC8911]

Thanks!!!!