Here is one reverse engineered from something in my junk box:
--- sam : Repair FAQs: "http://www.paranoia.com/~filipg/REPAIR/Repair.html"
This is the type of common light dimmer widely available at hardware
stores and home centers.
The 3-way type can be used to replace a regular 3-way switch used to control
a light from two separate locations. However, note that it is not possible
to use 2 of these 3-way dimmers to have independent control from 2 locations -
only one can be a dimmer.
S1 is part of the control assembly which includes R1.
For a normal dimmer, S1 is just an SPST switch.
While designed for incandescent or heating loads only, these will generally
work to some extent with universal motors as well as fluorescent lamps down
to about 30 to 50 percent brightness. Long term reliability is unknown for
these non-supported applications.
Black 1 o--------o
\
S1 o----+------------+-----------+
| | |
Black 2 o--------o | R1 \ |
| 220 K /<-+ |
| \ | |
| | | |
| +--+ |
| | |
| R2 / |
C1 _|_ 47 K \ |
.047 uF --- / __|__ TH1
| | _\/\_ SC141B
| +---|>| / | 200 V
| | |<|--- |
| C2 _|_ D1 |
| .062 uF --- Diac |
| | |
Red o-----------------+---CCCCCC---+-----------+
L1
40 T #18, 2 layers
1/4" x 1" ferrite core
Date: 20 Nov 1996 20:35:07 GMT
Original Subject: Re: Light dimmer schematics?