I think I see the point about wiring two motors in parallel. Depending upon the motor design you might not want both "up" and "down" feeds paralleled together when only one is connected to the source at a time. You could get some unwanted interaction.
Looking at the diagram, why are they insisting that the neutral be fed via the control switch? If the neutral was just connected straight through at the box, then you could actually use the second half of the DPDT switch to operate a second motor simultaneously without the paralleling of the "unused" winding becoming an issue.
Re shades bouncing at the end of travel, do the motors/mechanisms have limit switches?
Re: The things you get in place of what you ask for!#62863 03/02/0607:55 AM03/02/0607:55 AM
actually E57, my first reaction was what jackasses. But after a moment of reflection, I have to agree with them.
How many times have you(or someone you worked with) looked at instructions or wiring diagrams and said "we don't need these"?
The installation is simple and makes sense. The motors obviously operate at slightly different speeds and they may have something internal in their switch that cuts the neutral as well.
It's obvious that this is not the first set of instructions that they wrote. Odd are, they are like the "caution: Hot Coffee" warning on a McDonald's coffee cup. A reaction to things that have happenened.
Don't get offeded by it. Manufacturers instructions are there for a reason. To CYA. If you follow manufacturers instructions, and there is a problem, it's not yours. Don't follow instructions and there is a problem, it's yours whether it is or not.
Re: The things you get in place of what you ask for!#62864 03/02/0609:38 AM03/02/0609:38 AM
I don't much like switched neutrals, but this technically does not appear to be a violation of 380-2(b) because of Exceptions #1 & #2. So, for me anyway, I'd figure if they wanted to pay me to wire it this way, I'd do it.
There are 10 types of people. Those who know binary, and those who don't.
Re: The things you get in place of what you ask for!#62866 03/02/0610:28 AM03/02/0610:28 AM
I can see their point. However, they could have been a little more diplomatic with the delivery. It is unprofessional to gig people on official statements. This sounds like it was put out on the fly by a ticked off service rep.
Re: The things you get in place of what you ask for!#62867 03/02/0612:16 PM03/02/0612:16 PM
If they didn't call it "motor common (white)" but called it say "motor return", and use say blue wire, the "switched neutral apparent violation" issue might go away. Or just note in the instructions "This conforms to 380-2(b) Exceptions #1 & #2" so an electrician would know that there are no mistakes.
[This message has been edited by wa2ise (edited 03-02-2006).]
Re: The things you get in place of what you ask for!#62869 03/02/0607:05 PM03/02/0607:05 PM
It is very possible that the neutral is not actually switched- just terminated to screws on the switch body. It is also possible that something in the switch, like a light, also needs to be connected to the neutral.
As for the harsh words in that sheet ..... well, at this site we see a lot of, well, "interesting" things done by unqualified folks who pretend to be electricians.
Ironically, one of my most regular "debates" with customers is my need to actually see the equipment, and the directions. Even if they have the things in their back pocket, they seem to resist my seeing them. I even had one guy say I "must not be much of an electrician" if I needed to see a wiring diagram!
I have one sunshade, and three projector screens under my belt. All used the same switch that is shown on that artwork- with the exception of the neutral. Otherwise, connections were as shown.
In a related manner, today I installed some switches that came with a little tag attached to the wires. The tag read "Wire to hot leg. Do Not attach to neutral." Hard to believe, but it appears that some folks out there are doing that....and POOF! :-)
Re: The things you get in place of what you ask for!#62870 03/02/0608:36 PM03/02/0608:36 PM
After taking a 4th or 5th sithing look at "How to stay out of trouble - for electricians", (It's file name as sent) I noticed that it is probhably page #7 out duffus' #uno's training manual.... From 1997....
Our PM's reply to the GC that forwarded it was that she found it both rude, and unprofessional.
My reply was...
OK, where is it that I can post my rebuttal? (“To how to stay out of trouble”) NO Joke…. (Re: wire diagram if one could call it such.)
404.2(B) Grounded Conductors. Switches or circuit breakers shall not disconnect the grounded conductor of a circuit.
If it were a relay… They could do that… i.e. switch a neutral.
430.85 In Grounded Conductors. One pole of the controller shall be permitted to be placed in a permanently grounded conductor, provided the controller is designed so that the pole in the grounded conductor cannot be opened without simultaneously opening all conductors of the circuit.
And I say that because I doubt their puny little switch can take locked rotor current… qualifying it as a controller.
430.82 Controller Design. (A) Starting and Stopping. Each controller shall be capable of starting and stopping the motor it controls and shall be capable of interrupting the locked-rotor current of the motor.
These will be controlling several of the largest shade motors of this type, that I have installed many times before, which operate ~4-5amps each to lift a 15X30 area of heavy canvas. When operating several of these at once, it is normally nessesary to have them controlled by relays due to combined amperage, and due to device finish (Vareo) the switches will not be a good match...
So I took a look at the Somfy site, and apparently that wiring diagram may be equally as old as his training manual. (And they may have realized that switched neutrals were a bad idea.) I seached thier whole set of diagrams and that one is not availabe, at least any more. They do however have this one, that still shows a switched neutral, but note, one motor. http://www.somfy.com/nam/file.cfm/acdiagrm.pdf?contentID=11702
Either way, nothing of what I was sent was a "Cut-sheet" or "Specification"! No "Specific" make/model number, FLA, or dimensions for the shades, location of feed, or what will control them per scope of work.
Mark Heller "Well - I oughta....." -Jackie Gleason