3 Battery Generating System

[ewizard]

Hi Matt

I have just order or the PCB board will shipped to Sweden within 10 days it cost 142$ three boards pro including shipping to sweden.
And I will continue shopping the other parts and it’s hard to find 500w transformer here in Sweden so I have to order it also or I can use the same transistor I use it for the small setup of your tesla switch which is 250w does it work ?
And if it is then shall the wire gauge be #18 and 40 feet long 8 wires and 40 turns or less?
One more question it’s about these 1/8w resistors I have many resistors ½ and ¼ w and 1w can I use them instead of the 1/8 w ?
Ehsan

Ehsan, I don't believe anyone answered you about the resistors. In case you haven't come across the answer yet I think I can answer that one for you. As long as you can physically fit them into the PCB or your circuit (shouldn't be a problem as you can stand them upright if needed) a ½ and or a ¼ watt resistor will always work fine when it calls for an 1/8 watt resistor. It will give you an extra margin of safety even as the only difference in resistor wattage ratings is their ability to handle the total power running through them. So the bigger the better in most cases with the possible exception of extremely high frequency circuits where the extra size might alter some things. I don't think that would be any problem here.

[ehsanco1062]

Ehsan, I don't believe anyone answered you about the resistors. In case you haven't come across the answer yet I think I can answer that one for you. As long as you can physically fit them into the PCB or your circuit (shouldn't be a problem as you can stand them upright if needed) a ½ and or a ¼ watt resistor will always work fine when it calls for an 1/8 watt resistor. It will give you an extra margin of safety even as the only difference in resistor wattage ratings is their ability to handle the total power running through them. So the bigger the better in most cases with the possible exception of extremely high frequency circuits where the extra size might alter some things. I don't think that would be any problem here.

Hi ewizard

Thank you ,that's what I thought but I want to be sure that those resistors can
fit into the PCB ,and you make it clear

[ewizard]

Hi ewizard

Thank you ,that's what I thought but I want to be sure that those resistors can
fit into the PCB ,and you make it clear

In the past if I had any wire lead sizes that wouldn't quite fit a PCB hole I would either use a tiny drill to enlarge the hole a bit or I've even used a Dremel to grind down the diameter of the leads a bit. Anything to save buying another 2 cent resistor

[blackchisel97]

I have one of these (made back in 70') fitted into small DC motor from a toy. - Mini Keyless Chuck 3/32" Shank For Micro Drill Bits | eBay
It works great for drilling PCB's.

Vtech

[ehsanco1062]

Hi Matt

Before I will make my order I want to be sure that this Fet is Working fine or not
http://ixdev.ixys.com/DataSheet/DS99...-TQ50N25T).pdf
It's 250v 50A

Ehsan

[Matthew Jones]

Ya that might work. The big issue with it is a 400 watt, So you might run into problems with it. But you could parallel several if you find a weak point.

The biggest thing I am worried about is the cap dump portion. If your cap is say 10000 uf and you charge it to 48 volt and dump it into a 24 volt battery with that Fet you'll have a 100 nanosecond pulse of 24 volt at 480 amps. Those numbers are off

So you can see that might stress the Fet out a bit, but like I said you can give it a try.

Also make sure to include a good heat sink. Much over 40 deg Centigrade you are going to lower the conduction rapidly. So you wanna keep that little thing cool as possible.

Matt

[ehsanco1062]

Hi Matt

Thank you for the explanation although I didn't understand some of it because its above my understanding but I think it dose not worth to try and then blow some thing and then wait untill get the new order which it will be the same as you refer to in previous post I mean
IXFN180N25T-ND It's 155A 250v to be in the save side .
And I ordered also (338-1988-ND) it's 15000mf 100v cap
And this ultra fast diode (30EPH03PBF-ND) It's 300v 30A and the ather parts ar the same as Dave list.
These parts I orderes from Digi-key

Ehsan

[Matthew Jones]

Ya thats the safe way to go. You can always lean the system down later once you have all the power mapped out.

The thing you gotta watch is Watts, At least that been my experience. If the watts aren't high and the conduction is not high enough at Higher heat level than usually they don't hold up very well. The other thing you have to watch is the voltage of the transients. If the Bypass diode is not rated high enough the spikes will eat ya up.
Thats what I like about the IXYS miniblocks. They can take beating. They'll still burn up if your not careful but its easier to see whats going on then make the correct adjustment. They have High watt counts and that helps alot.

Matt

[shylo]

Partial Success

Hi all

I'm still working with the original set-up.
I can take 204 watts of power, off the dead battery,...I'm running 3 loads,

an 18volt cordless impact,
" " " " drill,
" " sawsall,
My primaries (good bats) hold and climb, when my switching is working.

If I could keep the switching working properly I'm sure it will run.

I've tried many different mechanical set-up's, but the wires eventually burn out

I have a generator connected to my motor that works off the positive of the dead battery ,and the positive of the # 1 ,good battery , this connects to the positive and negative of the #2 ,good battery.

The switching has to intterupt the flow to the coils(in the charger) at just the right time.

I checked the #'s on the tools (204W), but tried to check what the rad fan was drawing(it was more than 7amps dc,melted the test lead in my hand),

Trying to build some form of brushes or a switch, that's where the answer is.

shylo

[Turion]

shylo
Can you post a schematic? I'm a little confused, but then I'm always a little confused.
Dave

[shylo]

I don't use steel for back plates this was my 1st attempt

I tried using an old armature, and a set of brushes as a switch,it worked quite well,the only thing was the more area you cover with the brush,the more drag you create

But if you can make multiple connections at the same time ,in the right sequence, hence the switch

The only way is to reduce the size of the brush(or contact)

shylo

[citfta]

Questions

Hi shylo,
I am also somewhat confused. I hope you don't mind if I ask some questions to try and understand what you are doing. Also a schematic would be a big help.

Hi all

I'm still working with the original set-up.
I can take 204 watts of power, off the dead battery,...I'm running 3 loads,

an 18volt cordless impact,
" " " " drill,
" " sawsall,
My primaries (good bats) hold and climb, when my switching is working. What switching are you talking about? The original circuit only had the batteries and a motor and the load on the dead battery.

If I could keep the switching working properly I'm sure it will run.

I've tried many different mechanical set-up's, but the wires eventually burn out

I have a generator connected to my motor that works off the positive of the dead battery ,and the positive of the # 1 ,good battery , this connects to the positive and negative of the #2 ,good battery. Are you saying the output of the generator is connected to battery #2?

The switching has to intterupt the flow to the coils(in the charger) at just the right time. Is the charger the generator you have running off the motor that is connected to the positive of the good battery #1 and the positive of the dead battery?

I checked the #'s on the tools (204W), but tried to check what the rad fan was drawing(it was more than 7amps dc,melted the test lead in my hand), Is the rad fan motor the same as the motor that is turning the generator or charger?

Trying to build some form of brushes or a switch, that's where the answer is.

shylo

Thanks for any clarification you can give.
Carroll

[shylo]

Well I'm not good at schematics

[shylo]

sorry

I posted that before I was ready
This is my switch

The problem is the wires need constant observation.

shylo

[citfta]

Thanks shylo

Ok now I think I see what you are doing. You are using the coil shorting process that I have seen on some other forums. Are you shorting the coil multiple times at the peak of the voltage curve or only once? I have seen some circuits on this forum or another one for doing that electronically. I'll have to look for it if you are interested in going that way. If I understand the process right this shorting allows you to get a lot more power from the generator without any additional drag on the motor. Is that correct? So then you are able to keep the primary batteries charged while running the 3BGS. Thanks for sharing this with us.

Carroll