Re: 60 ma v.s. 30 ma
From: John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
Sent: Thursday, June 26, 1997 2:17 PM
To: Tesla List
Subject: Re: 60 ma v.s. 30 ma
At 04:44 AM 6/26/97 +0000, you wrote:
>Sent: Wednesday, June 25, 1997 7:19 AM
>Subject: Re: 60 ma v.s. 30 ma
>In a message dated 97-06-19 10:42:33 EDT, you write:
><< > If you add larger transformers, you can certainly also increase the
> > capacitance to take advantage of the higher charging current. All I'm
> > saying here is you do not have to increase the capacitor value when higher
> > current transformers are added. Some folks seem to think one requires the
> > other.
> Actually you do have to increase the capacitor size if you increase
> the charging current otherwise you will not be using the additional
> current. Realize of course this assumes that you were already using
> the largest practical size capacitor for the charging current. The
> capacitor is really the controlling factor as to how much power we
> can cram into a given Tesla coil.
>If you increase the supply current in a given system without changing the
>cap, you will get an increase in power delivered to the secondary and longer
>sparks. The cap will charge quicker, the gaps will fire more often and the
>system will process more power.
>Using my 14,400 volt pole pig and a .025 mfd cap - I can set the welder to
>limit the current supplied by the pig to say 100 ma. Now I get sparks that
>are X feet long. Now you are trying to tell me that if I increase the
>current up to 300, or 400 ma I will not get MUCH longer discharges??
> Apparently you have not tried this. I have and believe me you do not HAVE
>to increase the size of the capacitor to process more power.
As I mention in one of my books comparing a large pole pig transformer
output at a reduced level with the equal output of a small transformer is
not a proper comparison. The outputs may appear to be equal but other
parameters affecting the spark length will not be equal.
To get accurate data from the 30/60 ma test you will have to use 30 and 60
ma neons. Every size and type of transformer has its own unique
characteristics such as waveshape, percent impedance, etc., that affect
spark length. The neon is a current limiting transformer with completely
different characteristics compared to pole pigs.
Note also that the wattage of the transformer must be sufficient to
completely charge the capacitor for both tests. One of the biggest
difficulties that all coilers have in making tests is to do the test
correctly and to understand the results. I have found that sometimes when I
do a test over again that the earlier test was done incorrectly. It is a
good idea to do the test more than once.