Legrand Wattstopper DSW-301 Occupancy Sensor - 2 - Sensors Feeding A Single Fan

[Ravenvalor]

Hello,

I have a customer with a single 1/8HP rooftop exhaust fan serving 2 - restrooms. I would like to replace the existing toggle switch in each restroom with a Legrand Wattstopper DSW-301 occupancy sensor. Just like the toggle switches both sensors will be feeding the fan. Can anyone on this forum think of a reason why this might not work? The manual that comes with this sensor switch does not mention this type of configuration and it does not offer online or phone support.

Thanks for the help...

 

[tthh]

Seems fine -- the cutsheet says it works for 3-way applications up to 4 of them connected.

 

[Ravenvalor]

Seems fine -- the cutsheet says it works for 3-way applications up to 4 of them connected.

Thanks for the help.
The wiring diagram on the cut sheet shows one sensor feeding the other which feeds the motor. Plus it seems to imply for a single room. My application is 2 - separate rooms.

 

[tthh]

Thanks for the help.
The wiring diagram on the cut sheet shows one sensor feeding the other which feeds the motor. Plus it seems to imply for a single room. My application is 2 - separate rooms.

Two rooms with one sensor each is the same as one room with two sensors.

 

[LarryFine]

So the lights and fans in both rooms will all operate when triggered?

 

[tthh]

So the lights and fans in both rooms will all operate when triggered?

Yes. But, the description is there is only one fan that services both rooms.

 

[gar]

230803-1454 EDT

Ravenvalor:

Fundamentally the logic you want is a logical OR circuit. Two normally open contacts in parallel are such a positive logic circuit. So the question becomes will these devices perform this function if paralleled. I don't know. If they won't behave well in parallel, then you could use each to power a relay, and parallel the relay contacts.

..

 

[Ravenvalor]

Thanks for the great help. Nothing in the literature suggests parallel function.

https://www.legrand.us/lighting-controls-and-systems/occupancy-and-vacancy-sensors/wall-switch-occupancy-and-vacancy-sensors/dual-tech-wall-switch-occupancy-sensor-120-277v-white/p/dsw-301-w

 

[gar]

230803-1558 EDT

Ravenvalor:

I believe there is a high probability that you can parallel two or more of these devices, and get a useful OR operation if you do the following:

1. All sensors must be supplied from the same AC hot line.
2. The sensors must use the connection to neutral. This provides AC power to the sensors independent of any load.
3. Given the above I don't think it will matter whether the actual power switch in the sensor is solid state or a mechanical relay.

Experiment with two units on the bench.

.

 

[Ravenvalor]

So I decided to just go with the ceiling mount occupancy sensors with the powerpack/relay. It is a drop tile ceiling so the project should be quick and easy.

Thanks for the help.

 

[tthh]

Probably just a safer bet for callbacks and the long term.