Seasonal Light Equipment: Dimmer Kit

Date: Thu, 23 Nov 1995
From: Jonathan Yuen
Subject: Re: Dimmer Kit

Hello Lou,

The kit I bought was a Velleman Kit K2657, "Slow on, slow off dimmer". It can be wired either as a slow switch (turn it on and it comes on slowly, turn it off and it goes off slowly), or as a timer dimmer (turn it on and it's on immediately and after a while it starts to dim out). I think the kit is from The Netherlands since the first language on the instructions are Dutch. It costs me (guessing) about $40, which I thought was a lot at the time, but we do have high sales tax over here.

It wasn't that hard for me to put together, but I've built radios and things so soldering irons are no stranger to me. It was a printed circuit board that you just solder all the components to, and then you mount it in a box (that you have to supply). I mounted mine in a plastic box with two outlets mounted on it, and I connect it to the wall with a cord. You adjust the 'delay range' when you build it (you can choose which capacitors to install), and I chose the longer delay, from 5 minutes to 1 hour (variable). The final timing is done with a potentiometer (variable resistor). It will handle 2 amps as is, which will control 800 watts on 220 V and 400 on 110 V (it can be wired for either voltage).

I use mine with a normal wall outlet timer. When the timer goes to "on" (about 6 AM right now), the lamp I have connected to the "slow timer" starts to get brighter. After about 30 minutes it's at full brightness. This time is variable up to an hour, but I find 30 minutes works well for me. I have a normal 60 watt incandescent lamp on it right now, and I've been looking around for something a little more powerful.

I started playing around with using lamps to wake up over 20 years ago. I used to use normal timers but I've always found the abrupt transition from dark to light very disturbing. I had been planning to build a similar device for a long time but it wasn't till I read about the Velleman kit that I saw the solution to the "slow on" problem. We just started using it for the 3rd winter now, and I am quite pleased with the results.

I've heard of commercial units that do the same thing, but to my knowledge nothing is available here, and certainly not at the price I paid to put this thing together.

Let me know if there's anything else you want to know.

Jonathan Yuen
Department of Cancer Epidemiology
Uppsala University
Phone:  46 18 663944
Fax:  46 18 503431
Email:  Jonathan.Yuen@epic.uu.se

University Hospital
S 751 85 Uppsala
SWEDEN