How reliable are power meters on battery boxes?

[SkyChimp]

I bought a few batteries and boxes with power meters on them. I charged the batteries until my charger indicated a full charge. Once placed and hooked up in the boxes, the built-in meters indicate a full charge, but in only an hour or so its down to a 3/4, then 1/2 charge. The batteries and boxes are brand new, and the charger is less than 1 year old. This phenomenon occurrs with all the batteries. If I take them out of the boxes and try and recharge them again, the charger indicates they have a full charge. So I place them back in the boxes and the same thing happenes - full charge, then 3/4, then 1/2.

What gives? Do I have a couple of bum power meters on my boxes? Should I just ignore the power meters? Or do I have screwy batteries? Any ideas?

[Slab]

Don't know what to tell you. If the batteries are indeed charged, I'd trust the charger over the power meters, and just ignore the power meters. Another angle is, if the batteries are really loosing power, maybe the power meters are draining the batteries. I would try to chargte the batteries, check the power using the power meter (should have a full charge) then take it out of the box and wait overnight, and place them in the box again and see what they read. just a couple suggestions, hope that helps.

[fishintiger]

I bought a few batteries and boxes with power meters on them. I charged the batteries until my charger indicated a full charge. Once placed and hooked up in the boxes, the built-in meters indicate a full charge, but in only an hour or so its down to a 3/4, then 1/2 charge. The batteries and boxes are brand new, and the charger is less than 1 year old. This phenomenon occurrs with all the batteries. If I take them out of the boxes and try and recharge them again, the charger indicates they have a full charge. So I place them back in the boxes and the same thing happenes - full charge, then 3/4, then 1/2.

What gives? Do I have a couple of bum power meters on my boxes? Should I just ignore the power meters? Or do I have screwy batteries? Any ideas?

What kind of battery boxes did you buy? I got a Seasense battery box this spring. I also bought a battery charger and new battery. I charged the battery after using it. The charger said it was full. When I went to use it the battery box said it was only 2/3 charged. This was after it sat for probably a month without being used. Yesterday I took the boat out. I put the charger on the battery just to make sure it was full. The charger said it was full. After running the trolling motor for maybe 30 minutes it said it was down to 2/3 full. I think I'm going to get an external battery gauge and see if it reads the same thing. I was just wondering if you were using the same box I was.

[SkyChimp]

What kind of battery boxes did you buy? I got a Seasense battery box this spring. I also bought a battery charger and new battery. I charged the battery after using it. The charger said it was full. When I went to use it the battery box said it was only 2/3 charged. This was after it sat for probably a month without being used. Yesterday I took the boat out. I put the charger on the battery just to make sure it was full. The charger said it was full. After running the trolling motor for maybe 30 minutes it said it was down to 2/3 full. I think I'm going to get an external battery gauge and see if it reads the same thing. I was just wondering if you were using the same box I was.

BINGO!!!

All mine are SeaSenses

[PanMan_VA]

The best way to determine how much charge remains in your batteries is to measure the voltage. There is table in http://www.windsun.com/Batteries/Bat...ery%20Charging
that relates voltage to remaining power. It should help you figure out what the power meters on your battery boxes are trying to tell you.

[kmatcek]

I have a SeaSenses box and it says I am at discharge all the time even after charging a brand new battery. I do not trust the push button and will not buy another SeaSenses battery box just because of that. Btw I ordered it from Bas Pro Shops and it was too much of a hassel to send it back for replacement.

[SkyChimp]

I have a SeaSenses box and it says I am at discharge all the time even after charging a brand new battery. I do not trust the push button and will not buy another SeaSenses battery box just because of that. Btw I ordered it from Bas Pro Shops and it was too much of a hassel to send it back for replacement.

Me, too

[papasage]

i have a load test to teat a battery that is the onley way to see if it will hold up . my troling motor has 4 or 5 lights on it push a button and it will let you know how musch charge is in your battery . it is ent acurate but like a gass guage they want be that close .wheni check my battery on the troling motor it doesent show full charge . you will have to learn where full charge is . with light like that they have to go off when the battery gits low enough to the light off . like my holding tank in my camper it . the full light comes on befor it is full . wouldnt want it to come on when it is full. gives it a leadway

[Moose1am]

Just get ahold of a good digital Volt meter (DVM) not doctor of veternary medicine LOL and check the batteries voltaage between the positive and negative terminals on the battery without the battery hooked up to anything else. Then hook the battery back up to the battery box terminals and then use the DVM to check the voltage on the battery terminals of the battery box.


Now are the voltage readings the same? If so all is ok. If not then you are losing voltage or electrons somewhere. Try tightening down the terminal connections between the battery box and the battery's terminals.

What type of wire is used to connect to two? Is it very thin aluminum wire or thick copper wire. Copper wire 8 gauge may work better as the larger diamter the wire and the more strands of copper wires and the shorter the connection the less resistance you will see. More electrons will flow though the wires with less resistance. Heat also effect the wires resistance. Heat causes the coppper atoms to move further apart and that makes it harder for the electrons in the outer orbitals of the copper atoms to jump from one copper atom to another copper atom. When you super cool copper wire it's atoms are squeezed tighter together and then the electrons find it easier to travel from one atom to the next atom. Note: The electrons in the atom itself may not move closer or farther away from the center of the atom unless you really heat the atom up really really hot. Then you are chaging the copper into another element. Even in a solid like copper the atoms move somewhat. Not nearly as much as those atoms in liquids but still they move around some in the solid material.

[fishintiger]

BINGO!!!

All mine are SeaSenses

That be the same one I've got. The funny thing was last time I charged my battery before this past weekend I hooked it up to the box probably 5 or 10 minutes after the charger said it was full. The meter on the box showed fully charged. I think I will have to get a DVM and check it out. I don't think I will be buying another one of these boxes. They just seemed like it would be easier to use but I think I was wrong. I really liked the idea that I could attach everything outside of the box and not directly to the battery. Maybe next time I will save a couple of dollars and buy the cheap box.