Battery charger fun..
Posted: Mon Aug 07, 2006 9:51 pmWell, after shooting my mouth of about how good the Swallow charger was:
http://www.modelflight.com.au/rc_model_ ... harger.htm
I thought that I should get one myself.
So, having grilled my friend about his, and talking to a guy in Adelaide who I have a sneaking suspicion is the importer, I went to Monaro Hobbies in Queyanbeyan and laid my readies down.
(Keeping in mind that this would impact on my disposable income for a bit)
Now, you all should know that in a previous life, I was an aircraft technician. Big deal, you say.
I was also fairly heavily into radio control model aircraft.
What this tends to instill into someone is the importance of not skimping on things.
The aeromodelling community pretty much nailed down Sanyo as the better performing ni-cads a LONG time ago. Most don't use anything but. Sanyo pretty much lead the field in the NiMH field as well, although the field has leveled out in the last few years.
When it comes to seeing your $2000+ model plunge out of the sky and impale itself in someones paddock/Mercedes/girlfriend, you tend to want to make sure that things are going to be reliable.
As a whole, aeromodellers also tend to like battery chargers.
Unfortunately, my pulse charger, which works fine, but has it's detractors has run out of capacity. It just doesn't seem to see any cells over 2000mAh.
Bugger.
See if you can find a NiMH under that these days.
So with the transition to the new cells, and my aquiring of a D200, it was about time to update the charger to a more capable unit.
Enter the Swallow. (Dramatic music)
For about 99 dollars (not including freight) you get a digital charger which will charge Lithium Polymer, Lithium Ion, SLA, Nicad and Nickel- Metal Hydride batteries.
It's about as big as a packet of cigarettes. (And costs about the same as 12 of them. Next year, 8 ). It's also a nice blue colour. God bless anodising.
With only banana jacks for output, you're free to make whatever leads you need to connect this baby up.
I elected to buy some banana jacks, wire and alligator clips from Tricky Dicky's to make some universal leads for mine. A few various plugs let me plug it into almost everything I have that has batteries.
So another 4 dollars away, some soldering and I'm ready to test.
The charger has four buttons which let you select the various options. It also has warning modes if you do something stupid.
It even spells it out so you are in no doubt what has happened.
Essentially, the first step once you've connected it up to a power supply of some kind (11 - 15 volts DC) is to select your battery type.
At this point, I should mention that my power supply is a 7AH Gell Cell or SLA ( Sealed Lead Acid ) obtained from Jaycar for the princely sum of about 17 dollars. It sits on a wall wart charger constantly which blinks at me when it's filled the battery.
After selecting your battery type, your next steps will then be determined for you. For Li-Po or Li-Ion, you will need to set your Capacity and Voltage.
You can then set a charge, or discharge/charge cycle.
The Capacity and voltage settings will determine the safe charging currents.
With Nicads and NiMH's, the fun begins with setting your charge current , discharge current terminal discharge voltage and number of charge/discharge cycles.
You can charge from between 1 - 14 cells with this baby.
You can also pump up to 5 Amps into your selected cells if you choose to. Fair warning though. Some of your cells might not be there when you return.
Some batteries were not designed for fast charging.
When in doubt, you can charge most things at their "C10" charge current. This means that you should be able to put 1/10th capacity per hour into it over ten hours. Or, for a 2300mAh battery, 230milliamps for 10 hours.
You never quite get all the current you put into a cell out, so a few hours at that rate extra generally is no problem.
But bugger that. That's what we've bought a charger for.
On to the results and the handy thing. At the end of a nicad/NiMH charge, you can disconnect the battery and hold the Battery Type button down for three seconds.
It then gives you some information screens you can step through to give you information about the charge and discharge capacities of the batteries you've just jammed full of current.
I tested my two transmitter batteries. One is a 600 mAh nicad pack. It was replaced in 1994. It also hasn't seen much use as it's the spare. After the first discharge cycle, it was at 383 mAh discharge capacity.
Bugger.
After programming the charger for 5 charge / discharge cycles at 1 amp discharge and 200 milliamps charge, the capacity came up to 580mAh!
Yehaa. That's well and truly enough for a day's flying..
On to my main transmitter which is a 1700 mAh Sanyo SCR fast charge equipped behemoth.
Hmmm. Batteries not replaced since 1996. Not used much in the last few years either.
These batteries can handle a charge current of 2.5 Amps for an hour if you really want to pump it in.
I decide to remove the pack from my transmitter just this once. Yes. I'm a chicken.
Hoping sincerely that the laminex wouldn't bubble, I adjusted the charge current to 2.5 Amps and stood back.
A short time later, the alarm went off to tell me that the charge had finished. I'd only pumped 500mAh into it, so decided that as the batteries were only mildly warm, I could safely let it cycle a few times.
Setting 1 amp discharge (which is the maximum it will do) I then let it cycle 4 times.
Result?
1800mAh in the old 1700's. Gotta be happy with that.
Now.
I have a problem with buying spare Nikon batteries for the D200, so I have 12 x 2300 Sanyo NiMHs.
With the single Enel3 (or whatever it is) in the MB-D200, I can clip the leads with the alligator clips onto the battery tray. The little screws retain the clips without marring the mating surfaces of the battery tray contacts.
With a few cycles at 200mAh, the battery capacity was up to an average of 2400mAh over the six batteries.
Yehaa!
I could even charge all 12 of them at the same time if I decided to clip the 3 dollar battery holders together.
Just for fun, I think I'll try pumping 5 Amps into the old battery pack I removed from my Uniden walkie talkies.
I'll do it in the shed and post results when it gets warmer.
If you're after an easy to drive and capable charger that will do a wide range of battery types, I can recommend this device.
http://www.modelflight.com.au/rc_model_ ... harger.htm
I thought that I should get one myself.
So, having grilled my friend about his, and talking to a guy in Adelaide who I have a sneaking suspicion is the importer, I went to Monaro Hobbies in Queyanbeyan and laid my readies down.
(Keeping in mind that this would impact on my disposable income for a bit)
Now, you all should know that in a previous life, I was an aircraft technician. Big deal, you say.
I was also fairly heavily into radio control model aircraft.
What this tends to instill into someone is the importance of not skimping on things.
The aeromodelling community pretty much nailed down Sanyo as the better performing ni-cads a LONG time ago. Most don't use anything but. Sanyo pretty much lead the field in the NiMH field as well, although the field has leveled out in the last few years.
When it comes to seeing your $2000+ model plunge out of the sky and impale itself in someones paddock/Mercedes/girlfriend, you tend to want to make sure that things are going to be reliable.
As a whole, aeromodellers also tend to like battery chargers.
Unfortunately, my pulse charger, which works fine, but has it's detractors has run out of capacity. It just doesn't seem to see any cells over 2000mAh.
Bugger.
See if you can find a NiMH under that these days.
So with the transition to the new cells, and my aquiring of a D200, it was about time to update the charger to a more capable unit.
Enter the Swallow. (Dramatic music)
For about 99 dollars (not including freight) you get a digital charger which will charge Lithium Polymer, Lithium Ion, SLA, Nicad and Nickel- Metal Hydride batteries.
It's about as big as a packet of cigarettes. (And costs about the same as 12 of them. Next year, 8 ). It's also a nice blue colour. God bless anodising.
With only banana jacks for output, you're free to make whatever leads you need to connect this baby up.
I elected to buy some banana jacks, wire and alligator clips from Tricky Dicky's to make some universal leads for mine. A few various plugs let me plug it into almost everything I have that has batteries.
So another 4 dollars away, some soldering and I'm ready to test.
The charger has four buttons which let you select the various options. It also has warning modes if you do something stupid.
It even spells it out so you are in no doubt what has happened.
Essentially, the first step once you've connected it up to a power supply of some kind (11 - 15 volts DC) is to select your battery type.
At this point, I should mention that my power supply is a 7AH Gell Cell or SLA ( Sealed Lead Acid ) obtained from Jaycar for the princely sum of about 17 dollars. It sits on a wall wart charger constantly which blinks at me when it's filled the battery.
After selecting your battery type, your next steps will then be determined for you. For Li-Po or Li-Ion, you will need to set your Capacity and Voltage.
You can then set a charge, or discharge/charge cycle.
The Capacity and voltage settings will determine the safe charging currents.
With Nicads and NiMH's, the fun begins with setting your charge current , discharge current terminal discharge voltage and number of charge/discharge cycles.
You can charge from between 1 - 14 cells with this baby.
You can also pump up to 5 Amps into your selected cells if you choose to. Fair warning though. Some of your cells might not be there when you return.
Some batteries were not designed for fast charging.
When in doubt, you can charge most things at their "C10" charge current. This means that you should be able to put 1/10th capacity per hour into it over ten hours. Or, for a 2300mAh battery, 230milliamps for 10 hours.
You never quite get all the current you put into a cell out, so a few hours at that rate extra generally is no problem.
But bugger that. That's what we've bought a charger for.
On to the results and the handy thing. At the end of a nicad/NiMH charge, you can disconnect the battery and hold the Battery Type button down for three seconds.
It then gives you some information screens you can step through to give you information about the charge and discharge capacities of the batteries you've just jammed full of current.
I tested my two transmitter batteries. One is a 600 mAh nicad pack. It was replaced in 1994. It also hasn't seen much use as it's the spare. After the first discharge cycle, it was at 383 mAh discharge capacity.
Bugger.
After programming the charger for 5 charge / discharge cycles at 1 amp discharge and 200 milliamps charge, the capacity came up to 580mAh!
Yehaa. That's well and truly enough for a day's flying..
On to my main transmitter which is a 1700 mAh Sanyo SCR fast charge equipped behemoth.
Hmmm. Batteries not replaced since 1996. Not used much in the last few years either.
These batteries can handle a charge current of 2.5 Amps for an hour if you really want to pump it in.
I decide to remove the pack from my transmitter just this once. Yes. I'm a chicken.
Hoping sincerely that the laminex wouldn't bubble, I adjusted the charge current to 2.5 Amps and stood back.
A short time later, the alarm went off to tell me that the charge had finished. I'd only pumped 500mAh into it, so decided that as the batteries were only mildly warm, I could safely let it cycle a few times.
Setting 1 amp discharge (which is the maximum it will do) I then let it cycle 4 times.
Result?
1800mAh in the old 1700's. Gotta be happy with that.
Now.
I have a problem with buying spare Nikon batteries for the D200, so I have 12 x 2300 Sanyo NiMHs.
With the single Enel3 (or whatever it is) in the MB-D200, I can clip the leads with the alligator clips onto the battery tray. The little screws retain the clips without marring the mating surfaces of the battery tray contacts.
With a few cycles at 200mAh, the battery capacity was up to an average of 2400mAh over the six batteries.
Yehaa!
I could even charge all 12 of them at the same time if I decided to clip the 3 dollar battery holders together.
Just for fun, I think I'll try pumping 5 Amps into the old battery pack I removed from my Uniden walkie talkies.
I'll do it in the shed and post results when it gets warmer.
If you're after an easy to drive and capable charger that will do a wide range of battery types, I can recommend this device.
