Using a Power Supply without batteries

[Sailorman375]

I currently have an old (don't know the brand) Charger/Power supply that run my 24 volt systems without going through the battery banks. I like this set up for living aboard in marina with shore power. I want to replace the unit and am looking at a Samlex charger/power supply. My 24 volt loads are my fridge, a portable freezer, a water pump and a few lights. I'm looking at a 15 amp unit. I think I read somewhere that it might be a problem for the fridge as they need to be run through the batteries. Any thoughts. I do have two battery bank with a separate charger, but I have a switch that by passes the batteries which I like as I don't need to constantly charge and discharge the banks.

[Florida Mike]

First thing I would say is, don’t fix what ain’t broke. If the unit you have is working correctly why would you replace it? The only problem you will face without the batteries available is a start load for your refrigerator and freezer especially if they were to try to start at the same time, i.e. after a power failure. Just my two cents, Mike.

[Sailorman375]

The old charger is probably at least twenty years old and lacks the front cover, it's large, heavy and show corrosion. I guess It just plain scares me a bit.
If I need more amps so be it. I just want to sleep better, not having to worry about this old one burning up and starting a fire.

[Florida Mike]

If your present power supply has been adequate then replacing it with an equal sized unit should work just fine. I’m one of the type people that would take it apart clean it up and put it back together build a front cover and maybe even put a fire alarm close to it. I’ve found that a lot of older stuff is built better than the new stuff. Please let us know what ever you do. Again just my two cents, Mike.

[djmarchand]

Battery chargers (power supplies to use your term) need to be hooked to a battery. The battery acts like a buffer and absorbs current spikes caused by motors starting.

You said that you don't want the batteries charging/dischargiing if you leave them connected. That won't happen except for a necessary fraction of a second to start a motor. If the charger output is greater than the electrical demands, the batteries will never be discharging. Also leaving a modern 3 step charger hooked up to batteries will not harm them.

David

[AnchorageGuy]

Our Iota battery chargers can run the boats DC systems without even having a battery attached. Chuck

[Sailorman375]

I know about Iota and this feature. I wanted to find a PS/Charger that in the future could charge multiple banks. Any other brands have this feature?