LMA Genesis - Electric

[Andy Boylett]

HI Andy

Thanks for a masterclass in electronics lol I never use lipos as i just cannot understand them nor the charging of them at all, so I stick with metal hydride packs.
I will have to get a friend of mine to decipher your pics etc and see if he can make one for me ! as I still am little wiser as how to do it, inspite of the well documented pics you have kindly supplied, as my electronic understanding capability is NIL !
With the One diode fitted for each battery packs, ( fitting TWO seems even more complicated ! + what size diode is needed ??) and the TWO battery leads to the reciever, am I then able to use a spare reciever socket other than just the ONE battery output on the spektrum 7000 reciever ?
also are the two reciever on/off + charging switches, fitted to the aircraft as normal on/off swithes are ??
Being dead cheeky ! perhaps you could even make me one and i will pay you what you want?

God If i only had a brain !!!

Mike

Mike,
I was thinking about this today when making another unit and there is a really easy way to do this. If you want to use 2 batteries, each with its own switch then it is possible to just solder one diode into each of the switch leads. No circuit board and no unit required. I'll make one up and photograph it.
Cheers,
Andy

[Mike Ellis]

HI Andy
Are you going to be kind enough to answer my queries i asked you about , regarding your batterry backer? I really would like to make a couple,the same as you use, if I can be sure of HOW to do it.

Many thanks in anticipation.

Mike

[Andy Boylett]

Hi Mike,
Sorry, I havn’t been using the forum much and I missed that message with the questions – answers below:

1: What rating ? are the diodes, and where can we get them from ?
I use the 16amp schottky diode MBRF1645 from RS Components here
http://uk.rs-online.com/web/p/products/6881997/?cm_mmc=UK-PPC-0411-_-google-_-3_EEM_MPN-_-mbr1645_Broad&gclid=CPyB8tGNu6sCFWMntAodUDDTdA

2: Your diagram indicates TWO +VE IN and TWO -VE IN, but the unit picture indicates 4 soldering strips , so, could you make it a little clearer HOW
Positives and Negatives are connected, I would assume that THREE terminals are positives and ONE only, for ALL negatives?
If you look at the lower copper strip you will see 2 holes on the left for –ve in and 2 holes on the right for –ve out.
Now, if you look at the upper 3 copper strips you will see on the left that the upper and lower strips are for the 2 +ves in. Both of these +ves are then connected to the middle of the 3 strips by the diodes. Hence on the right the middle copper strip is for +ve out. You could use one wire for the +ve out (and the –ve out) if you want. I use 2 just to split the current onto 2 separate points on the receiver.

3: As the positives & negatives OUT, are common,would it be practical to have just ONE reciever lead , and NOT TWO as shown, or do we have to have the two leads for connection to TWO ports in the reciever.
Yes, one wire for each is fine. I only use 2 to split the load when using high current digital servos.

4: How are the Batteries now charged? do they need to be disconnected and charged individually or is there another way of doing it.
Each battery has its own switch that connects it to the input on this board. I use 7.4volt LiPos so they are always removed and charged away from the plane in a fire-proof bag. If using NiMH you could charge each by is own switch harness.

5: It appears that BOTH batteries are online once the on/off switch or switches is activated , is this correct ??
No, each battery has its own switch. Turning either switch on powers up the plane, but obviously both switches need to be on to have both batteries connected.

Cheers, Andy

[Andy Boylett]

Mike,
These are the lower rated 5amp diodes that I also use. They just happen to be on Ebay now.......
http://www.ebay.co.uk/itm/2-X-SR5100-5Amp-100Volt-Schottky-Rectifier-Diodes-/260852219704?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item3cbc00ff38

These diodes lend themselves to being fitted into a battery feed wire so they can be built very simply into the positive from each battery. What I have done on one model is to use 2 batteries and 2 switch harnesses, with both switch harnesses connected to the receiver. The positive wire in each switch harness has been cut and one of these diodes soldered into each wire, then sealed with heat shrink tube. This is very simple and very neat.
Regards, Andy