X10 Community Forum

🔌General Home Automation => Automating Your House => Topic started by: robster on October 17, 2006, 02:13:07 PM

Title: Multiple WS467s in one junction box?
Post by: robster on October 17, 2006, 02:13:07 PM
I have several locations where I have 3, 4, or 5 switches in one junction box, with one switchplate covering them all.  Can I replace all of the switches with WS467s?  I thought I had read a few years ago that this was not advisable, due to heat issues.  I have searched here for the last hour and cannot find any relevant articles, FAQs or postings.  Does anyone have experience or advice for me?    ???

Thanks,     Rob
Title: Re: Multiple WS467s in one junction box?
Post by: Puck on October 17, 2006, 02:55:51 PM
I have one location with 3 X10 controlled switches, but of those 3 only one is a dimmer. I originally had the same concern and monitored it closely; but found I had no issues.

HOWEVER.... 3 to 5 dimmers might be another story! Particularly if all happen to be on low brightness at the same time.

If you can use switches as opposed to dimmers where possible, the heat generated will be less.

I had a tough time getting the wires arranged in the box for my 2's & 3... I'd hate to work inside a 4 or 5.  :D
Title: Re: Multiple WS467s in one junction box?
Post by: Charles Sullivan on October 17, 2006, 03:24:14 PM
I have several locations where I have 3, 4, or 5 switches in one junction box, with one switchplate covering them all.  Can I replace all of the switches with WS467s?  I thought I had read a few years ago that this was not advisable, due to heat issues.  I have searched here for the last hour and cannot find any relevant articles, FAQs or postings.  Does anyone have experience or advice for me?    ???

Thanks,     Rob

You'll need to derate the WS467 from it's nominal 500W rating.  This article:
  http://kbase.x10.com/wiki/Switches_Get_Warm_In_Normal_Operation
recommends no more than 400W per switch for two in the same box or 300W per switch  for three in the same box.

It would appear that you'll be OK if the total lamp load is less than 800 or 900W for the box,


Title: Re: Multiple WS467s in one junction box?
Post by: robster on October 17, 2006, 03:53:51 PM
Thanks for the quick responses, guys!  As I will only use these for on/off applications, with a load of less than 200 watts per switch, and definitely less than 500 per junction box, it looks like I'm in good shape.  I'll monitor it closely, but at least I know this ought to work out OK.  Thanks again!  Rob ;D
Title: Re: Multiple WS467s in one junction box?
Post by: JeffVolp on October 18, 2006, 09:27:57 AM
Quote
HOWEVER.... 3 to 5 dimmers might be another story! Particularly if all happen to be on low brightness at the same time.

Actually, maximum heating occurs at maximum brightness.  The heating is caused by conduction through the triac.  Voltage drop is about a volt, so dissipation is almost 1 watt per 100 watts of load at maximum brightness.
Title: Re: Multiple WS467s in one junction box?
Post by: Puck on October 18, 2006, 09:49:17 AM
Actually, maximum heating occurs at maximum brightness. 

JeffVolp: Thank you for the correction. Guess I've been a paper pusher to long, forgetting some of my practicle.  ::)

robster: Here is link for some addition info:

SMARTHOME: Is it normal for wall dimmer module to get warm to the touch? (http://www.smarthome.com/solution41.html)


[TTA Edit: Added description to LINK.]
Title: Re: Multiple WS467s in one junction box?
Post by: gil shultz on August 08, 2007, 12:16:14 PM

Good Afternoon,

Yes you can, I have 8 in one box next to another that has 8.  I used metal boxes because I could gang them and more importantly I could get rid of the heat.  The primary heat dissipation from the X10 module is the aluminum cover, typically an isolated triac is connected directly to it so it can get rid of its heat. 

Yep putting a non isolated triac in that unit causes fireworks if the metal box is grounded and a shock hazard if it is not.

The others are on the right track.  Try not to put the heaviest loads next to each other.  You may want to derate the modules to an average of about 400 watts Max each.

Enjoy the toys, I do.
Gil Shultz
Title: Re: Multiple WS467s in one junction box?
Post by: Walt2 on August 08, 2007, 02:36:15 PM
Actually, I have trouble physically fitting two X10 wall switches next to each other.  They are just slightly wider than the spacing between "holes" in multi-gang plates. 

Doesn't the problem only get worse when you have 4 or 5 of them right next to each other?
Title: Re: Multiple WS467s in one junction box?
Post by: gil shultz on August 17, 2007, 02:22:31 AM
Good Evening,

You are correct, they are about 1/16 wider then the boxes I bought at Home Depot.  The boxes I used are left over from a home I built in the mid 70’s, they are just a bit wider. 

That leaves a few other fixes, you can file the aluminum on the WS467 to make them a bit narrower but be careful. 

Every three or so units put in a switch or plug that will allow you to make up the room.  In my California room I have about 14 outlets that have the WS467 on the top receptacle only; this along with the wireless remote makes a nice setup. 

However sometimes we want the plugs to be “normal” so each unit is connected so the adjacent switch shorts the WS467 out.  The current then flows through the switch not the dimmer.  We can plug in vacuum cleaners or whatever else we like. You can open the little switch below the button isolating the WS467 from the load if you like.  The WS467s and companion switches are actually mounted in the basement ceiling and are not accessible from the room.

Have Fun
Gil Shultz
.
Title: Re: Multiple WS467s in one junction box?
Post by: steven r on August 17, 2007, 12:56:07 PM
...However sometimes we want the plugs to be “normal” so each unit is connected so the adjacent switch shorts the WS467 out....
Hmm... Interesting approach. It could be a nightmare to explain to a cleaning person or even my mom when she visits.  I also don't know what building codes would think of a dimable outlet even with the override switch.
Title: Re: Multiple WS467s in one junction box?
Post by: Puck on August 20, 2007, 06:05:24 PM
I also don't know what building codes would think of a dimable outlet even with the override switch.

I hate to see someone loss their home over an electrical modification / suggest posted here. Check your local codes; if it's not allowed, don't do it unless you can afford to lose your home. Cause if it was determined to be the fault, I doubt the insurance company will give you money.
Title: Re: Multiple WS467s in one junction box?
Post by: gil shultz on September 05, 2007, 11:58:50 PM
Good Evening,

It did pass code and was approved by the chief inspector.  There is no fire hazard, all the wiring is done with #12 Stranded pulled in conduit.  If the wrong thing is plugged in it will blow the dimmer switch.  The switch can only fail in one of two modes shorted on or open.  Shorted on will only conduct the amount of current the load requires.  If it is a bolted short it will either explode the triac or trip the breaker.  I have only lost two switches in about five years.  They all have tungsten lighting plugged into them so putting something in that should not can only happen if something is removed.  So we told the cleaning lady only plug into the bottom, never into the top and that solved the problem before it happened. Everything is contained in metal, not plastic.

This room is also our home theater so depending on the area some codes may be different.

Good Luck
Gil Shultz
Title: Re: Multiple WS467s in one junction box?
Post by: Puck on September 06, 2007, 12:36:47 AM
"The National Electrical Code® (NEC®) prohibits the dimming of standard receptacles."

LUTRON For Your Information... Guide to dimming portable lamps via receptacles (http://www.lutron.com/applicationnotes/048085b.pdf)
Title: Re: Multiple WS467s in one junction box?
Post by: dave w on September 06, 2007, 11:55:48 AM
Good Evening,

 There is no fire hazard, all the wiring is done with #12 Stranded pulled in conduit.  If the wrong thing is plugged in it will blow the dimmer switch.  The switch can only fail in one of two modes shorted on or open.  Shorted on will only conduct the amount of current the load requires.  If it is a bolted short it will either explode the triac or trip the breaker. 

Good Luck
Gil Shultz

You are presuming the switch will always be the weakest link. Plug a notebook computer's switching power supply or a xformer wall wart with load, into the outlet and dim the switch 40%.

What overheats and smokes, may not always be the switch. BTW did the inspector have alcohol on his breath when he inspected?
Title: Re: Multiple WS467s in one junction box?
Post by: steven r on September 06, 2007, 01:53:40 PM
...did the inspector have alcohol on his breath when he inspected?
If it was an X10 wall switch, the inspector probably didn't realize it could be sent a dimming command. On the other hand, had it been actually a conventional dimming switch that he overlooked, then I would support either "alcohol on his breath" or the "money under the table" theory.

BTW.. Would an appliance have a tendency to try to draw more current, less current, or just fail to operate if its voltage supply were reduced below its normal operating requirements.
Title: Re: Multiple WS467s in one junction box?
Post by: steven r on September 06, 2007, 02:22:16 PM
As a kid (pre or early teens) and before I knew what a split outlet was, one of my experiments involved running a wire from the live side of an outlet on the other side of the room to override a switched outlet. Things got a little safer when I found out how rewire the outlet as a split one.

Then there was the experiment where I ran current from the live side of an outlet through a bulb to the grounded metal ring around the bathroom sink. The spark left a permanent mark on the sink. I never said anything about it and fortunately no one else said anything if they noticed it.

While educational and in the case of the wire across the room useful, I doubt an inspector or my parents would of been very happy had they realized the extent of some of my electrical experiments.
Title: Re: Multiple WS467s in one junction box?
Post by: dave w on September 07, 2007, 12:41:39 PM
...did the inspector have alcohol on his breath when he inspected?
If it was an X10 wall switch, the inspector probably didn't realize it could be sent a dimming command. On the other hand, had it been actually a conventional dimming switch that he overlooked, then I would support either "alcohol on his breath" or the "money under the table" theory.


Yup I agree. I hope Gil gets my point that he can't assume that the X10 dimmer can be counted on to fail in some kind of a "safe" mode i.e full ON or full OFF (this might be a safe assumption if a vacuum cleaner, is plugged into the outlet). Instead, an inductive or switch-mode device plugged into the outlet may fail in a disasterous manner(i.e. max flame).
Title: Re: Multiple WS467s in one junction box?
Post by: gil shultz on October 20, 2007, 01:09:35 AM
Good Evening,

You are correct the 2002, 2005 and 2008 National Electrical Code forbids dimming split outlets in section 404.14.  However I could not find it in the 1993 NEC (I do not have all of them).  I contacted the inspector and asked what code they use.  They use the state Residential Code which does not prohibit dimming.  Consequently what I have is legal and to code in this state.

On a side note the inspector is an honest man and does not drink, so I do not know where you got that from.  Maybe you can buy them off where you live but here it gets you time.

I did a bit of research and there is a lot about that particular section of code, promoted by Lutron.  A bit of further research shows they have a patent on there system consequently there will not be another brand that is interchangeable.  They also got the UL approval and limited to only there dimmer.  Hmmmm I wonder why?

Any idea how 404.14 became part of the code and who promoted it? 

As far as plugging in laptops, little bricks etc they may or may not work.  If they are UL or CSA approved (they should be) there will be no fire or anything like that although they may get hot and blow there thermal protection. 

It is important to also check local regulations as well.  A lot of communities do not subscribe to the NEC, some are much more stringent some are more lenient but that varies by section.

Have Fun
Gil Shultz