RE: TSG construction article

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Pete Komen by way of Terry Fritz <twftesla-at-qwest-dot-net>" <pkomen-at-zianet-dot-com>


Hello Ted and Ed,

As I understood it, the resisters across the output of the dimmer keep the
triac turned on during the time that the current is building up in the coil
primary.  The low resistance kept the jitter and noise in the circuit down.
The problem with the inductive load is that the triac can turn off due to
lack of holding current (while the inductor current is building) and on
again.  When this happens many times in succession during each half cycle,
the triac burns out.

http://www.epanorama-dot-net/documents/lights/lightdimmer.html#inductive
has some information on dimmers.

I remember a site that had a modified dimmer with an extra triac to keep
voltage on the gate of the power triac to avoid the above problem in driving
an inductive load, but I can't find it.

Regards,

Pete Komen


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Tuesday, December 18, 2001 8:05 AM
To: tesla-at-pupman-dot-com
Subject: RE: TSG construction article

Original poster: "Ted Rosenberg by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Ted.Rosenberg-at-radioshack-dot-com>

Ed (and anyone else who is listening):
I certainly agree with you about placing the resistors across the line.
Frankly, I think there was a communication breakdown. I believe Marc said,
sometime ago, that it was some sort of accident that they got used at all.
Now, as for their usefulness in series between the dimmer and the HEI hot
line, well, honestly I admit to lacking the theoretical powers to say yea or
nay. In such cases I graciously defer to the others on the list. I just
build the stuff and cross my fingers like everyone else. I've been fortunate
so far that the money sucker works so well  :)).
I am thinking of transferring the discrete components to a small printed
circuit board quick connectors. if anyone can tell me for sure that the
resistors can be left out, it means less work for me.

Safety First

Ted