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#96112 - 11/04/05 07:44 PM Occupancy sensor
George Little Offline
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Registered: 01/18/04
Posts: 1488
Loc: Michigan USA
210.70(A)(1) Exception No.2 talks about an override capability and my question is- What gets overridden- the turning on or the turning off? And what does the overriding? duh
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George Little
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#96113 - 11/05/05 12:21 AM Re: Occupancy sensor
Tesla Offline
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Registered: 06/16/04
Posts: 1273
Loc: Sacramento, CA
The 1st exception is clear: it allows bedroom wall switches to control one or more suitable receptacles that will be subsequently used by the resident to heat up free standing lamps.

In the code, an outlet is taken to be a direct wiring of a light fixture -- in this instance -- whereas it is so common to have no overhead light fixture in the bedroom: all lights are to be lamps.

This style of lighting may include a more substantial space such as a living room.

The Second exception allows for occupancy sensors in lieu of traditional switches. Think of WattStoppers and its rivials. These can be dropped in directly to replace ordinary switches. They can also be wired in series with traditional switches.

These 'new' devices are what is addressed. Again, they are switching wall receptacles that are intended to heat up free standing or table lamps.



[This message has been edited by Tesla (edited 11-05-2005).]
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#96114 - 11/05/05 03:02 AM Re: Occupancy sensor
iwire Offline
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Registered: 01/05/03
Posts: 4391
Loc: North Attleboro, MA USA
Quote:
What gets overridden- the turning on or the turning off?


George I am glad you asked as that is something I have wondered.

Most of the wall switch motion sensors I have installed can only be overridden to the 'off' mode. To override them to 'on' usually means getting into the adjustment section.

Here is the exception George is asking about.

Quote:
210.70(A)(1)Exception No. 2: Lighting outlets shall be permitted to be controlled by occupancy sensors that are (1) in addition to wall switches or (2) located at a customary wall switch location and equipped with a manual override that will allow the sensor to function as a wall switch.


I have a related question.

Quote:
110.26(D) Illumination. Illumination shall be provided for all working spaces about service equipment, switchboards, panelboards, or motor control centers installed indoors. Additional lighting outlets shall not be required where the work space is illuminated by an adjacent light source or as permitted by 210.70(A)(1), Exception No. 1, for switched receptacles. In electrical equipment rooms, the illumination shall not be controlled by automatic means only.


Does this rule out a motion sensor even if it can be overridden?

Bob
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Bob Badger
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Massachusetts
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#96115 - 11/05/05 05:13 AM Re: Occupancy sensor
resqcapt19 Offline
Member
Registered: 11/10/00
Posts: 2148
Loc: IL
Bob,
Quote:
Does this rule out a motion sensor even if it can be overridden?

If it can be overridden, it is not "automatic only".
Don

[This message has been edited by resqcapt19 (edited 11-05-2005).]
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#96116 - 11/05/05 05:24 AM Re: Occupancy sensor
iwire Offline
Moderator
Registered: 01/05/03
Posts: 4391
Loc: North Attleboro, MA USA
Don the question still remains which way must the override work?

Override it ON, OFF or both?

It seems self explanatory that in the Elec room you would want to override the light ON but it does not say that.

I think there may be a conflict with the energy codes with a ON override.

Bob
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#96117 - 11/05/05 06:00 AM Re: Occupancy sensor
Tiger Offline
Member
Registered: 05/04/05
Posts: 706
Loc: Crystal Lake, IL USA
Leviton's Occupancy sensor that replaces a switch is Catalog No. 6768. (if anyone can provide a link).

It states in the catalog "Push-botton manual override allows controls to be used like standard ON/OFF switches;

manual-ON/Auto-OFF mode"

I read that as the unit overriding the ON.

Dave
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#96118 - 11/05/05 07:02 AM Re: Occupancy sensor
HLCbuild Offline
Member
Registered: 12/05/04
Posts: 209
Loc: Herndon,Va USA
Seems to me if it is required to function as a wall switch, it must be able to turn on and off...just as a wall switch will do.
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#96119 - 11/05/05 09:04 AM Re: Occupancy sensor
gfretwell Offline


Member
Registered: 07/20/04
Posts: 9038
Loc: Estero,Fl,usa
If it replaces the wall switch it is clear it must have both manual on and off capability. The question is with "in addition to..."
Basically is the M/D wired in series or parallel?
I think it is ultmately a design decision. I have about 20 in and out of the house so can argue both sides of that ;-)
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#96120 - 11/05/05 01:35 PM Re: Occupancy sensor
HLCbuild Offline
Member
Registered: 12/05/04
Posts: 209
Loc: Herndon,Va USA
I think it would have to be wired in parallel. If it was in series and the primary wall switch were in the off position it would not allow the motion switch to "function as a wall switch".
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#96121 - 11/05/05 06:25 PM Re: Occupancy sensor
Tesla Offline
Member
Registered: 06/16/04
Posts: 1273
Loc: Sacramento, CA
These switches -- WattStopper, etc. -- inregards to 210.70 (A) exception 2 are for habitable spaces.

In all my days, I've never installed one in an electrical or service room.

The energy conservation rules kick intelligence in at 100 square feet whenever it would not create a hazard.

If you're in the room, the automatic feature triggers it on...with a delay after your departure.

You can kill it anyway so as to permit viewing movies, TV, or sleeping.

The device logic always requires power ahead of its own switching. So the automatic switch is in series with the manual override built into the device.
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