Regarding dimmable fluorescents.  They have one big advantage in that the
color or temperature does not change with dimming. You do not gain bulb life
by dimming, like you do with incandescents.  There are various types of
dimmable fluorescents.

Advance Transformer (Rosemont Illinois, USA) makes the Advance Mark X, which
connects to a normal type dimmer (dual SCR or TRIAC).  It dims down to 5%,
but in their spec sheet this is a voltage of about 60 VAC.  Below that the
tubes flicker, so you need either a control system with definable start
points or a dimmer with a trim for the low end.  They also make the Advance
Mark VII, which uses a 0-10 VDC control signal for dimming.  Many companies,
including Lutron, make various types of dimmable ballasts in either of the
above formats.

A company that has a cool line of dimmable ballasts is Energy Savings,
(Schaumburg, Illinois).  They have a line of digitally controlled ballasts
that are quite afordable, compared to the other companies in this arena.
They have an RS-485 type connection for controlling the ballasts.  The
protocol handles varying fade rates for on/off, and the dim level.  They
also make an RS-232 converter for their ballasts.  They have a number of
their own controllers but nothing elaborate.  This would be a cool PIC
project to control these ballasts.  The commercial marketplace is begging
for an afordable control system to handle these ballasts and other lighting
loads.





-----Original Message-----
From: pic microcontroller discussion list
[mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of David Duffy
Sent: Saturday, July 07, 2001 6:54 AM
To: PICLIST@MITVMA.MIT.EDU
Subject: [EE]: DSI Lighting Protocol


I came across some information for dimmable lighting ballasts
yesterday. You control them via a serial interface (called DSI).
I've searched but can't find out about the physical interface of
the protocol used either. ATCO (among others?) manufacture
the ballasts - I may try them to see if they will reveal all.  :-)
Does anyone know anything about this system?

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