Tesla Switch need help

[plengo]

@Groundloop

[Thaelin]

Hi
   Well that sure is a lot of trannies but if it works, great deal. I have finally decided to put together a relay powered one to play with. Had to pack the relays in foam to quiet them down. Was very surprised to find what I did.
   Using 4 4.5 ah 12v and driving a 1amp motor, I already have 4.5 hours run time logged and have dropped from 13v down to 12.8. I have a switch time of around 12 a second. I am depleting the batteries but at a very slow rate. At 1 amp, I should have killed the bats by now.
   So to conclude, I see this upping the run effective run time for the motor. As I intend to run an electric motor to power my bike, this should give me a greater distance of travel overall. Will look into solid state relays for the switching as they will trigger on 5 v and can use a 555 to run the pulse train with.
   The other board still has a heat problem with transistor 6 and I cannot figure out why. I have been over the circuit many times and its wired exactly as the diagram states.
   The only problem is if I lose a relay, I will have a dead short on one side every half cycle. Had to fuse between each pair and both sides as well. So far so good. More run time to see what will give.

   Next is to recharge and see how many consecutive hours run time the system will give without going below the 12.4 save level as these are the standard gel cells.

thaelin

[Groundloop]

@Thaelin,

If you look at the circuit diagram (some pages back) then you will see that there is 8 diodes also.
I use TO-220 diodes so that I can avoid any heat sink. The other six TO-220 is hexfets.

If we use some math on your circuit:

4,5 A/h * 4 * 12 Volt = 216 W/h.  Motor 12V * 1 A/h = 12 W/h so ideal maximal run time is 18 Hours.
(Much sorther if you do not want to deplete the batteries below a certain level.) I think the best load you
should have is the C20 rate of your batteries, approx. 10 Watt/h.

Groundloop.

[Groundloop]

Hi

Finally got my NiCad charger together. 

Next Job, soldering 4,8 Volt NiCad packs. Need four of them.
Then I must mount my electronic and batteries into a box.
Will take some time..............

Regards,
Groundloop.

[Thaelin]

   Hi all:
   Well guess its time to lay it down for all to see. I have finished my 4 batt switch and it runs using relays at 20 cps. I will be subbing them with SS relays so I can up the transfer time. I am able to have a 3 amp motor run under load for extreme long times. This motor will be used for an electric bicycle. From estimates I am seeing around 100 miles and that is with 4.5 ah batts. I actually will be using 18 ah  on the bike. Nothing will tell better than the trip out the highway soon. The motor will be driven by pwm from the 4 batt switch.
   I did notice that I had no output from the tesla switch with the two caps in place. As soon as I removed them, I then had over 12v and high amps available from the FWB output. The motor I use right now is an old windshield wiper motor from a 80's vintage GM. I got the largest motor available and it has a worm gear to another gear reduction. I use a 8500uf 85v cap to pad the output during switch times.

thaelin