# [TCML] quench times again

Chris Swinson list at future-technologies.co.uk
Sat Nov 24 06:01:03 MST 2007

```Hi Bart,

(demo coil)
230khz  Q281  TT=17.16  ET=7.81, 895 turns 24AWG DRC=27 17mH  8 pri turns,
ML= 85.663

(demo coil half turns, half length)
500khz  Q306  TT=7.65uS  ET=7.81,  400turns 24AWG DRC=12 3.5mH, 3.5pri
turns, ML = 15.87

(same as demo coil length)
500khz  Q403  TT=7.71uS  ET 7.87, 400 turns 18AWG DCR=3  3.5mH  3.5 pri
turns,  ML=15.773

So the length of the coil or the wire size does not seem important....

So if the we some round easy figures of 250khz to 500khz, thats 85ML and
15mL, So double the frequency is 5.5times less mutual inductance...

Now frequency vs transfer time.. double the frequency is half the transfer
time, which was the figures I was working with..

The 1/2cycle figures (ET) all seem the same. I think this makes sense if you
treat it more like current per cycle.not sure on how that works out....

The primary impedance though for 500khz is 48ohms, impedence for 250khz is
133ohms. So would have expected the current per cycle to be more..

I do see your point with ML though, this also alters along with the
frequency. Though ML figures seem hard to work with. Working towards double
frequency = half transfer time is my currnt way of thinking, which also
matches up with the coil data..

I would have expected ET to become half if it is taking longer to transfer
energy...

Chris

```