Several people have asked for details about how to build a battery power supply for their RCBS Chargemaster 1500 scale/dispenser. I thought I'd share the "how to's" here. It's a simple operation, just DO NOT, for any reason, reverse polarity to the scale. It'll kill it before you can blink!
On that note, you should know beforehand that RCBS does NOT warranty their unit if used with anything other than the original supplied wall wart power supply.
That said, the voltage supply is much smoother and more consistent from the 12v power supply that the unregulated wall wart that comes with the scale. Another benefit is isolation from strong power surges that can kill the scale, such as lightening. Not to mention, the obvious convenience of being able to use the scale without electricity.
There are other ways, as with most things, but this is how I made mine, along with pics and instructions.
The unit is very simple. You basically need three things...
1.)12v sealed lead acid rechargeable battery. I use a 12 volt 5Ahr rated battery and life has been excellent. Run times vary with how much it's actually running vs idle, but I've left mine plugged up for several weeks between charges.
2.) A charger appropriate for this battery and..
3.) The cables to hook it all up.
You'll also need appropriate terminal ends and I highly recommend red and black heat shrink tubing to color code the wires with. I like to solder all terminals on but crimp connectors will work.
The cables are common electronics cables and are referred to as 5.5mmx2.1mm DC plug/socket cables.
Here go's...
There are 3 cables. The first is the one at the battery. Here, I use a short female(socket) cable. Remember I said DO NOT reverse polarity!! Using the socket cable here allows the unit to be "plug n play", without the possibility of reversing polarity once the unit is assembled.
I split the wire, install terminal ends and heat shrink to the ends, then hot glue this short cable assembly on top of the battery. This socket will be used as a port to plug the battery to the charger and to the Chargemaster. Sorry for the fuzzy pic but hopefully, you get the idea.
Into that socket, plugs a male/male extension cable. You can see one end of it next to the socket adapter cable on the battery. It looks the same on both ends and should be identical to the end on the factory wall wart. The other end plugs into the Chargemaster. So, one end into the battery socket and the other end into the CM1500. At this point, once you have the terminals on the wires and attached to the battery, the power supply is ready to run the CM1500
Last but not least, is the charger. For this, your needs will depend on how your charger is made. Mine has simple screw terminals that accept spade terminals. So, that cable will be male on one end and open on the other..no terminals yet. I put those on and attach them to the charger. Now the charger is ready for use. Just plug the male end on the charger to the female socket on the battery to charge.
You can install a fast acting 1-1.25amp fuse in the positive cable at the battery if you like and it may add a safety factor against fire but it won't blow fast enough to save the CM1500 if you reverse polarity to it. Without it, I'd guess it's still many times safer than parking your car in your garage but, if it makes you feel better, it can't hurt to have it fused.
One other thing...I haven't mentioned which wires and terminals are +/-, and I'm not going to. I don't want anyone to blame me if they hook it up backward and fry their Chargemaster. A basic DVOM(digital volt ohm meter) will answer that. If you don't have one and know how to use it, you should contract with someone to build this for you, if you want. Very simple though...Just need a little basic knowledge of electricity.
I looked and only have a few cables left and have no batteries nor chargers. Batteries Plus should have the battery and charger and Radio Shack should be able to supply the cables.
I will help in any way that I can but battery terminal styles can vary, charger terminals can vary and you really need to attach the female socket cable to the battery anyway. So, with those variables, I can't assemble them and guarantee fit to your battery and/or charger.
Anyway, hope you enjoyed it and hope it helps someone just a bit.--Mike Ezell
p.s.--Once done, check the voltage from the factory wall wart vs. the battery power supply. It's very apparent which way supplies the most consistent current. Electronics generally don't care for voltage irregularities. For that matter, check the voltage coming into your house. It usually will vary up and down a fair amount.
On that note, you should know beforehand that RCBS does NOT warranty their unit if used with anything other than the original supplied wall wart power supply.
That said, the voltage supply is much smoother and more consistent from the 12v power supply that the unregulated wall wart that comes with the scale. Another benefit is isolation from strong power surges that can kill the scale, such as lightening. Not to mention, the obvious convenience of being able to use the scale without electricity.
There are other ways, as with most things, but this is how I made mine, along with pics and instructions.
The unit is very simple. You basically need three things...
1.)12v sealed lead acid rechargeable battery. I use a 12 volt 5Ahr rated battery and life has been excellent. Run times vary with how much it's actually running vs idle, but I've left mine plugged up for several weeks between charges.
2.) A charger appropriate for this battery and..
3.) The cables to hook it all up.
You'll also need appropriate terminal ends and I highly recommend red and black heat shrink tubing to color code the wires with. I like to solder all terminals on but crimp connectors will work.
The cables are common electronics cables and are referred to as 5.5mmx2.1mm DC plug/socket cables.
Here go's...
There are 3 cables. The first is the one at the battery. Here, I use a short female(socket) cable. Remember I said DO NOT reverse polarity!! Using the socket cable here allows the unit to be "plug n play", without the possibility of reversing polarity once the unit is assembled.
I split the wire, install terminal ends and heat shrink to the ends, then hot glue this short cable assembly on top of the battery. This socket will be used as a port to plug the battery to the charger and to the Chargemaster. Sorry for the fuzzy pic but hopefully, you get the idea.
Into that socket, plugs a male/male extension cable. You can see one end of it next to the socket adapter cable on the battery. It looks the same on both ends and should be identical to the end on the factory wall wart. The other end plugs into the Chargemaster. So, one end into the battery socket and the other end into the CM1500. At this point, once you have the terminals on the wires and attached to the battery, the power supply is ready to run the CM1500
Last but not least, is the charger. For this, your needs will depend on how your charger is made. Mine has simple screw terminals that accept spade terminals. So, that cable will be male on one end and open on the other..no terminals yet. I put those on and attach them to the charger. Now the charger is ready for use. Just plug the male end on the charger to the female socket on the battery to charge.
You can install a fast acting 1-1.25amp fuse in the positive cable at the battery if you like and it may add a safety factor against fire but it won't blow fast enough to save the CM1500 if you reverse polarity to it. Without it, I'd guess it's still many times safer than parking your car in your garage but, if it makes you feel better, it can't hurt to have it fused.
One other thing...I haven't mentioned which wires and terminals are +/-, and I'm not going to. I don't want anyone to blame me if they hook it up backward and fry their Chargemaster. A basic DVOM(digital volt ohm meter) will answer that. If you don't have one and know how to use it, you should contract with someone to build this for you, if you want. Very simple though...Just need a little basic knowledge of electricity.
I looked and only have a few cables left and have no batteries nor chargers. Batteries Plus should have the battery and charger and Radio Shack should be able to supply the cables.
I will help in any way that I can but battery terminal styles can vary, charger terminals can vary and you really need to attach the female socket cable to the battery anyway. So, with those variables, I can't assemble them and guarantee fit to your battery and/or charger.
Anyway, hope you enjoyed it and hope it helps someone just a bit.--Mike Ezell
p.s.--Once done, check the voltage from the factory wall wart vs. the battery power supply. It's very apparent which way supplies the most consistent current. Electronics generally don't care for voltage irregularities. For that matter, check the voltage coming into your house. It usually will vary up and down a fair amount.
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