Have a client with melted C4-Dim1-Z-x dimmers. The original installer obviously didn't figure on the rating for a multi-gang install.

Can these dimmers just be swapped or do the new dimmers need to be programmed into the system or activated?

programmed.

It will have to be re-id'd into the programming then refreshed.
and updated if it isnt already a switch at that operating system level.

The switch will work with programming as a dimmer until you add it in, so don't worry about leaving them in the dark. :)

Dont blame the installer yet... maybe the customer decided to swap the 75-100 watt bulbs in the place of the old bulbs and didnt see it as an issue until it melted.

CI

When implementing lightiing systems total potential load of the fixture or light sets should always be taken into consideration - not just the wattage of the current bulbs...

Thanks for the feedback. House is 3 years old with original lighting and the 3 gang box where this is happening has loads that are all original and fixture rated total loads of over 800w each. Should have been in separate boxes to start. I'll find an RC C4 dealer to reprogram. Thanks again.

:)

the dimmers are 1000 watts with both heat sinks, 800 watts with 1 removed and 600 watts with both removed

If its just 1 or 2 lights being IDed i can do it for you. THey need to have a 4sight account with a current subscription

This is both correct and incorrect.
The dimmers are 1000W with or without the tabs (what you are calling the heat sinks)

Everytime you add another dimmer to the electrial box you need to derate the dimmer.
1 Dimmer in a box is 1000 Watts.
2 Dimmers in a 2 Gang box is going to be 800Watts
3 Dimmers in a 3 Gang box is going ot 600 Watts and
4 Dimmers in a 4 Gang box is going to be 400 Watts.

You will need to reprogram any replacement dimmers with Composer You will NOT be able to do this with Composer Home.

Here's the center dimmer that took the brunt the damage. The other two were functioning but breaking down.

I think the homeowner is very lucky that the house didn't burn down.

Umm.. no i am correct.. You are incorrect. A dimmer with no heatsinks and a 1000 watt load = burn your fingers when you touch the screws or heat sink.. If you had 3 dimmers in a box like so

dimmer with 1 heat sink - dimmer no heat sink - dimmer with 1 heat sink then your rating would be 800 - 600 - 800

I would have to agree with kevin on this. aka blackwire

BTW to be clear the dimmer will still control 1000 watts with out the heat sinks but its going to be BURNING hot

They were lucky the damage was in the box only. I can understand the derating options. Normal derating the 800-600-800 would apply as you remove tabs on both sides on the center dimmer and only the inner tabs one on the side dimmers. Given this spec on C4's website though, they make it seem like as soon as you have 3 dimmers in a box, regardless of tabs or heatsinks, it is 600-600-600.

Good question for C4.

[Link: control4.com]

SDZD, you are correct.
Let me help BW here. Dimmer is a 1000W no matter what you do to it. Both tabs off it is still a 1000W dimmer. It's just rated for 600. Doesnt mean its still not a 1000W dimmer. You might have been correct if the description on the box said "1000/800/600 dimmer".

Yeah, but who cares if it's a 1000W dimmer if it's being installed in a spot where it has to be derated to 600W?