RE: Re: X10 Problems

[rj@xxxxxxx]

these lamps should not overheat, I have mine on for about 7 hours a day on
an appliance module.



-----Original Message-----
From: Nigel Orr [mailto:Nigel.Orr@xxxxxxx]
Sent: Thursday, 5 October 2000 12:04
To: ukha_d@xxxxxxx
Subject: RE: Re: [ukha_d] X10 Problems


At 10:12 04/10/00 +0000, you wrote:
>It says that on the module!  Does that explain the strange responses or
>just the flickering at full intensity?

They use triacs to control the light, which switch on when triggered, and
switch off when the current through them falls below a certain value.  That
means there is some dependence on the connected load, they don't behave
exactly like a relay.  Usually, the brightness is controlled by switching
the lamp on at a selected point in each half-cycle of the mains, then the
triac switches it off at the end of the cycle.

The flickering will be because sometimes the triac is switching off when
the current falls, sometimes it's staying on for the next
cycle.  Basically, it's confused and doesn't quite know if it's supposed to
switch on or switch off!

>   What are the consequences of
>running a lower wattage bulb, is the module at risk?

I wouldn't expect it to be, unless they've done some obscure tweaks for
other reasons... but it would reduce the control you have over the lava
lamp.

>   Given that I'm
>going to dim it I suppose it's safe(ish) to replace the bulb with a 40W
>one, thereby exceeding the maximum wattage of the lampholder?

No.  Well, it might be safe in carefully managed circumstances, but it
could cause a fire if the fitting is already marginally rated (particularly
if the module always comes on at full power- it could easily come on and
stay on when unattended if it interprets a glitch as an on signal).

So it's not technically safe, I wouldn't do it myself, at best a fault
would probably damage the wax in the lava lamp, at worst it would cause a
fire, but it's up to you how you assess the risk.

As Mark has hinted at, you could add an additional load, something that
will draw a few Watts (ie gets a little warm in use) but can cope with
being dimmed?  Another light would be ideal, maybe a nightlight or
something?  That would be the easiest solution, but may not be the
'neatest'.  It might be possible to modify the lamp module with a smaller
triac (reducing both it's minimum and maximum loads), but I've still not
even taken mine apart so I'll not try to advise on that!

The 'safest' X10 way would be to use an appliance module (which uses a
relay, so doesn't really mind switching small loads), and have code to
switch it off for a cooling period every 6 hours.  Actually, the real
safest way would be to have a thermostat in the lamp which runs it at half
power if it starts to overheat, but that would cost more...

Nigel





-------------------------- eGroups Sponsor -------------------------~-~>
Tellme Sports. Tellme Stocks. Tellme News. Just Tellme.
Call 1-800-555-TELL and hear everything. For info visit:
http://click.egroups.com/1/9529/9/_/2065/_/970688084/
---------------------------------------------------------------------_->