Bigger Coil= Bigger Output?
bomber315, Wed Nov 26 2014, 01:21PMIt seems like sort of a dumb question, but as much as I have been reading i can not figure out:
Tuning aside, if a certain interrupter, driver, and bridge were put on a physically larger coil, would that coil make more output on the same primary voltage?
Basically, I have a onetesla coil now and i want more. I know there a million factors but if i used the onetelsa interrupter, UD 2.7B, and a bridge similar to onetesla's operating on the same (120v in with a doubler and 2 or 4 FGA60N65SMD) could i expect more output on a 4" or 8" (diameter) secondary. I'm currently getting about 22" streamers from the onetesla.
I'm trying to build a "life sized" coil, that isnt going to break the bank.
Thanks!
Re: Bigger Coil= Bigger Output?
Steve Conner, Wed Nov 26 2014, 02:00PM
Efficiency of a tesla coil depends on the ratio of spark length to secondary length. To get a big spark out of a small coil, you have to dump lots of energy into it, but slowly to avoid flashing it over. This slow energy transfer leads to less efficient streamer growth.
If you are running a ratio much greater than 2:1, that means your electronics are too powerful for your resonator and you could get more spark length (in absolute terms, not ratio) from a bigger resonator.
Even with an optimally sized resonator, the spark length will never be much more than John Freau's benchmark. He predicts a spark length in inches equal to 1.7 times the square root of the power input from the wall. So if your electronics can handle 1kW without burning up, your maximum spark would be about 54".
Steve Conner, Wed Nov 26 2014, 02:00PM
Efficiency of a tesla coil depends on the ratio of spark length to secondary length. To get a big spark out of a small coil, you have to dump lots of energy into it, but slowly to avoid flashing it over. This slow energy transfer leads to less efficient streamer growth.
If you are running a ratio much greater than 2:1, that means your electronics are too powerful for your resonator and you could get more spark length (in absolute terms, not ratio) from a bigger resonator.
Even with an optimally sized resonator, the spark length will never be much more than John Freau's benchmark. He predicts a spark length in inches equal to 1.7 times the square root of the power input from the wall. So if your electronics can handle 1kW without burning up, your maximum spark would be about 54".
Re: Bigger Coil= Bigger Output?
Sulaiman, Wed Nov 26 2014, 02:14PM
from memory, John Freau's formula is for 60 Hz (r)sgtc
I have easily exceeded the spark length by using a lower break rate
for the small sgtcs that I have made, spark length is something like K.sqrt(Joules per bang)
(e.g. 12" sparks from 1.4 W dc input ... but not impressive)
which of course equates to watts at a fixed spark rate.
Sulaiman, Wed Nov 26 2014, 02:14PM
from memory, John Freau's formula is for 60 Hz (r)sgtc
I have easily exceeded the spark length by using a lower break rate
for the small sgtcs that I have made, spark length is something like K.sqrt(Joules per bang)
(e.g. 12" sparks from 1.4 W dc input ... but not impressive)
which of course equates to watts at a fixed spark rate.
Re: Bigger Coil= Bigger Output?
bomber315, Wed Nov 26 2014, 05:05PM
hmmm i didnt expect such a complicated answers.... maybe i should restate my question...
Can i take the the driver board from a oneTesla coil and attach it to a bigger coil and expect bigger sparks with the same input voltage?
bomber315, Wed Nov 26 2014, 05:05PM
hmmm i didnt expect such a complicated answers.... maybe i should restate my question...
Can i take the the driver board from a oneTesla coil and attach it to a bigger coil and expect bigger sparks with the same input voltage?
Re: Bigger Coil= Bigger Output?
Sulaiman, Wed Nov 26 2014, 06:34PM
I think that for a given power and frequency a larger coil (with thicker wire) and topload
will give a longer spark
but the (spark length)/(secondary height) ratio will decrease
and
I think that a small coil with big sparks looks better than a large coil with slightly larger sparks
Sulaiman, Wed Nov 26 2014, 06:34PM
I think that for a given power and frequency a larger coil (with thicker wire) and topload
will give a longer spark
but the (spark length)/(secondary height) ratio will decrease
and
I think that a small coil with big sparks looks better than a large coil with slightly larger sparks
Re: Bigger Coil= Bigger Output?
bomber315, Wed Nov 26 2014, 06:44PM
ok then i suppose instead of winding a bigger secondary and worrying about a topload, i should worry about finding a source for high voltage... Not really looking to go 220v tho, my landloard may not approve :(
bomber315, Wed Nov 26 2014, 06:44PM
ok then i suppose instead of winding a bigger secondary and worrying about a topload, i should worry about finding a source for high voltage... Not really looking to go 220v tho, my landloard may not approve :(
Re: Bigger Coil= Bigger Output?
Thomas W, Wed Nov 26 2014, 09:33PM
From what I have seen:
Bigger Coil = Bigger Output = Bigger Input = Bigger Wallet
Thomas W, Wed Nov 26 2014, 09:33PM
From what I have seen:
Bigger Coil = Bigger Output = Bigger Input = Bigger Wallet
Re: Bigger Coil= Bigger Output?
dillon, Sat Aug 08 2015, 05:14PM
size of secondary has large impact on the q of the coil. true watts multiplied by q will equal reactive watts.
dillon, Sat Aug 08 2015, 05:14PM
size of secondary has large impact on the q of the coil. true watts multiplied by q will equal reactive watts.
Print this page