your inductive loads round the house won't be too bad.
you could've just set all triacs up for zero crossing firing to get round the
transient headaches.
you could then analyse each inductive load to find out if any need a phase
delay.
not that any of this is relevant now , since you have relays.
glen
************

Isto Virtanen wrote:

> At 21:02 19.5.1999 -0500, you wrote:
>
> >My wife and I plan to build a house someday ( if I live long enough ) and I
> >plan to build the home automation system myself.  Mainly because I think it
> >will be the ultimate learning experience for me but also because most the
> >the HA products lack elegance or are just plain ugly ( at least to me ).
>
> Just about to get the house ready <G>. I have studied machine automation,
> has got B.Sc in it, but havent got any change so far to build/design a
> single automated machine/robot, so I just HAVE TO build my own HA system.
>
> I have evaluated several ways of doing this (X10, LON, PC-based centralized
> systems), but ended up with the same solution as You. LON is too expensive,
> X10 is not too common in 220V, centralized systems need too much cables and
> are not that flexible etc. Also the fact that after building and
> programming it by Yourself You can allways replace some nodes with
> something else if the supplier of Your current hardware should fail.
>
> I shall have 5-6 nodes each controlling app.12 relays through local
> switches and rs485 network. There will also be some special nodes for the
> heating, air conditioning etc.
>
> Not having the time anymore to desing a complete solution I shall set up a
> simple system to get the lights running: some 4013 dual flip-flops will run
> ULN2804 chips to power up some 70-80 relays around the house. After moving
> in I shall start developing the final system with PICs. I can later utilize
> those buffers and relays anyhow.
>
> WWW.PICPOINT.COM has got a sub-page PICNET+ run by Mr tanzilli. He (they)
> have got some nice ideas about runnng a RS485 network and have actually a
> dimmer node also (w. local and net-control)
>
> >This is an on-going project in my mind that changes as I learn more.  Right
> >now, I plan to use a PC for the master controller connected to PIC nodes
> >via RS485. This recent discussion is relevant because I would like to be
> >able to control the lights, fans, etc. via a PIC node.
>
> Exactly my schema. Local nodes would take care of lights in most cases but
> some buttons could also send the information into net in order ro turn on
> some remote lights (bedroom->hall->kitchen etc).
>
> >I would
> >also like to be able to control inductive and resistive circuits with the
> >same design for simplicity and to allow me to just make one batch of PCBs.
>
> To play safe I shall use relays for running all 220V loads. I am aware the
> fact that a semiconductor would have a longer lifetime, but relays are so
> much easier to handle: no mysterious spikes/inteference in the mains
> because of triacs/thyristors.
>
> Have just bought 80 relays (finder 40-series,spco) and waiting to get my
> hands on rest of the parts from Farnell.
>
> isto