Chargers New Parallel Charging System

[Heliman450]

So, it looks like that woke it up...................

The Watts for channel 1 are set to 285 (99%). When I enter 100%, the Watts drop down and transfer over to channel 2 so it's not possible to set both channels to more than 50/50 or channel 1 to more than 99%.

 

[Heliman450]

Hi all, weather's looking good for tomorrow so I've done some research on the limitations of my charging system according to the specifications and thanks to our tests from yesterday, I now know how to programme the charger to give its maximum capacity. Thanks to Steve and Uri for spending time with me.

Unfortunately, with my large batteries (6S 5000mAh) it doesn't give me much headroom. The absolute maximum according to my settings is two 5000mAh batteries per channel. To achieve this, I must trick the charger into thinking it has 6000mAh connected. This will give a 6A charge rate to each channel. If I connect two batteries to each channel it will be using 144W with a specified limit of 120W per channel (2 x 5000mAh = 10A).

I'm due to test this tomorrow morning and find out how long it takes to charge up six batteries.

 

[Smoggie]

Phil,

Good to see the 'little white lies' did the trick!.. I'm sure there will be some hidden 'expert user' options somewhere in the programming that allows you to do it without the lies but as long as it's working all is good!

By the way, if you set the charger to a higher charge rate than it's capable of delivering nothing bad will happen, it will just run at it's maximum and stop there.. you dont get it bursting into flames or any such excitement.

 

[Heliman450]

Hi Steve, I didn't expect the charger to destroy itself but my concern lay more with the batteries. I've finished the charging for this evening ready to fly early tomorrow morning. Weather looks ok but I'm expecting to be a bit chilly.

I did six batteries, which had all been used for about 9mins. So far the longest for these particular examples. I set up the charger to give 99% of its capacity to channel 1 and connected up two batteries. I programmed the 10,000mAh and achieved a charge rate as shown below in the photo. It took 52mins to charge 3,594mAh to each battery. So far my fastest charge rate.

The next charge was with four batteries (2 per channel) set up as normal 5,000mAh batteries and 50/50 capacity to each channel. It gave a charge rate of 5A. I increased the amps on each channel to 5.5A and then 6A. The rate increased at first to around 5.5A but only went up to 5.6A when the rate was set at 6A. This took 86mins to do the four batteries. This is all much faster than I was previously able to achieve. I'm still waiting for the three balance extensions so can't test any more right now.

I also checked out the charger you pictured earlier on in the thread. It's a real monster! Mine tops out at around 25A with a setting of 30A, so I suppose is a demonstration of your comment above. Without being able to tap into the control software, there's no way to increase. By the way, I dropped the capacity percentage when 'kidding' the charger with the 10,000mAh to prevent it from over-charging the batteries and it terminated as expected with a constant current 'soaking' after the constant voltage charge.

 

[Smoggie]

Phil,

There is no risk at all of the charger over-charging the batteries regardless of what mAh capacity you set. The mAh capacity that you set only determines the rate of charge (Amps), not 'how much' charge. The charger terminates based only on battery voltage. By default the charger will stop charging when the battery cell voltage gets to 4.2V, the mAh you set makes absolutely no difference to this.

 

[Heliman450]

Hi Steve, thanks for the insight on that. The instructions don't give any information about the control functions. However, there are lots of things to set that could be construed as control parameters and setting the percentage definitely did stop the charging process. A bit short, but nevertheless, acted as a limiting factor. I suppose the programmable time would also stop the process. Main thing is that the final control is there to stop any overcharging............ gives one a nice warm feeling without burning the house down

One thing that comes out very clearly is the safety note as follows: 'Connect ONE Battery to ONE Channel. Otherwise, either the batteries or the charger may be damaged. And it will be a cause of fire'. The ultimate cover for the rear end.

 

[Heliman450]

Hi again Steve, managed to do four batteries at the field and have charged two of them to go back making four to use this afternoon before going to meet up with friends.

I used the 10,000mAh route and it took 39mins 43sescs. Next time I'll enter extra amps and see how far I can go until the charger meets its limit.

 

[Heliman450]

Hi all, so it works like this.........

The default charging rate is 1C. It isn't possible to override this and save anything greater into the memory. Each time one wants to charge a single battery at greater than this the additional amps need to be entered either by choosing a charge rate in 5A increments manually from a drop-down list or to enter the desired value by increasing in 0.1A increments.

Before doing this, it's necessary to check the split of the charger's capacity between the two channels (normally 50/50) and increase channel one to 99%. Using a saved profile for a 'fudged' capacity (in 5,000mAh multiples) it's possible to load channel one in multiples of 5.0A as above. The charger will start its run until it reaches its 25A output limit. I haven't tried it on a single battery as this would mean charging at 5C. However, with four batteries (2 per channel), it won't go above 25A output.

So by my thinking, if I ever get round to connecting 8 batteries they will only be charging at around 3 amps each i.e. 0.5C. Looks like I've bought a pup if I ever want to do 8 batteries at 1C.