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Power supply and battery connected together?

Cutlass327

Cutlass327

Well-Known Member
May 1, 2016
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NE Ohio
I am running my Galaxies with a 30A switching power supply set at 14V. When I turn on all accessories, I notice that when I key it drops to 12V or less. I have a 12V sealed acid battery here, was going to hook them up, but the power supply is not a "battery charger". Would it cook the battery? Do I need a battery charge controller to protect the battery? Right now all I have is a float charger on it, but I figure the power supply would add output and keep up with demand faster than a Harbor Freight float charger. I was told that the P/S will not cook it, but I just wanted a 2nd (or more) opinion on that thought.
 

Is it dropping 2 volts at the radio, or the power supply? Without knowing what you are using for a power supply I don't want to comment much further, but it should be ok.
 
It is dropping at the power supply connection. I have a 3 Farad cap in parallel with the p/s to help cushion any spikes and it drops too as I figured it would.

I am using this p/s. I tried to copy/paste the link, but it isn't working. This is the heading of the listing from Amazon:

eTopxizu 12v 30a Dc Universal Regulated Switching Power Supply 360w for CCTV, Radio, Computer Project
 
How much current are you drawing? Sounds like either you are drawing more than the supply can handle or that the regulator in the supply is not working properly. FWIW I am not a great fan of switching power supplies. They are much harder to troubleshoot that the big old heavy linear type supplies. I run a couple heavy linear type supplies but did break down and buy a server type switching 50 volt supply for a special project I am working on but that's it for switching supplies. Yeah......I am old school.
 
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I'd love to have a good one, but I figured a Palomar 250 Elite and Galaxy 88HL wouldn't pull over 30A, and for $20, I'd give it a shot.

That setup worked fine, but I have a Shooting Star 225 Plus for SSB, and it is pulling the system down even on low power. My only ammeter is a DVOM and max of 30A unfused, so I don't dare connect it to test.

Would it matter if the 225 was on the battery and the radio on the p/s? I was afraid of a mismatch of sorts from 2 supplies, so I haven't tried it.
 
Your battery will never go above 12 volts,might not even put out a full 12 volts. Get a good old school power supply like cptn said old heavy linear style. I got a simlex i got new in 78 and it holds 12.4 volts when talking on 38 lsb on my galaxy 99v
 
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To use that switching supply or any supply with your battery, you’ll need a way to “disconnect” the supply from the battery once a certain charge level is reached. So you’ll need a controller of some sort or you’ll boil the battery over, overcharge it basically and that will ruin it.

Also don’t forget that batteries give off a gas, best to keep them in a sealed container that is vented to the exterior of your shop/shack/house or whatever. Been there and done that with a bank of deep cycle batteries in the past. And a bank of batteries will work if you have something that can keep the charge up on them.

I ran a bank of 4 deep cycles in my shop with a 140 amp alternator ran by a 120v AC motor. The bank was inside the shop in sealed containers and the “charging” system was outside the shop controlled by a switch. The alternator had a built in regulator so it could switch itself out of line when the voltage was up on the batteries. Not the best system or idea but it worked and I was able to run big amps for testing or whatever I chose to do.

I’ll agree with others, buy an old style power supply if money permits, a lot less headache and fiddling if you do. If you can’t afford it and have all that other crap laying around, cobble yourself together a makeshift bank and charging system.
 
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I would only spend money on a MegaWatt power supply and they are sponsors of WorldWideDX.
A battery that is fully charged will read 13.8 Vdc with no additional power applied and a short time to stabilize.
 
I hooked a battery to a linear supply one time to test out a subwoofer amp on a pair of 15 inch subs. It was fine until the bass hit. The battery fried fhe transistor for the crow bar circuit. So I ripped the transistor out ..... The Megawatt is advertised as being able to charge batteries. When the battery charge comes up to supply voltage then there is no difference of potential so the current goes to zero. The charger will float the battery so there is no danger in overcharging. I would run a separate supply for radio and amp but that's just me.
 
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Well I stand possibly corrected huh? What if that supply is at 14.5 volts, wouldn’t hurt that battery? I’m asking cause I’m not sure myself.
 
TheRealPorkchop said:
Well I stand possibly corrected huh? What if that supply is at 14.5 volts, wouldn’t hurt that battery? I’m asking cause I’m not sure myself.
Click to expand...
Well if a vehicle charging system typically charges at 14.7v then it would be like having the battery in a vehicle. The battery will only take what current it needs to recharge. The gassing of the electrolyte comes from when the battery is discharged and is taking current to recharge. There are some good articles I will find again on this. I learned a lot about this from my other hobby, car audio. The gell cell and AGM batteries are safe for indoor and inside the vehicle without a battery box. Traditional flooded wet cell batteries would need a sealed box and would need to be vented to the outside because of the outgassing of Hydrogen from the charging process. A friend of mine ran a car stereo in his bedroom when we were kids. He had an old car battery and a 10A battery charger to keep the battery up. One day he took the gator clamps off of the battery posts while it was still plugged into the wall. It jumped a spark and blew the top clean off the battery. I had to help him to the bathroom to get the acid washed out of his eyes. I will never forget that for sure.
Chris
 
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