Wireless controlled lighting - Emergency Circuits

[designer82]

I'm reviewing drawings for a school and they specified a lighting control system that is completely wireless.

Basically, there are wireless gateways that distribute the communication signal throughout with each light fixture having an individual wireless controller.

Some fixtures are designated "emergency" and fed by the life safety branch.

I can't put my finger on any specific code requirement but does this seem code compliant?

 

[don_resqcapt19]

How does it make sure the EM lights turn on when the normal power to the lights in the area is lost?

 

[designer82]

How does it make sure the EM lights turn on when the normal power to the lights in the area is lost?

I was thinking along the same lines. My thought is to require verification that the control equipment is listed for emergency use.
That is what 700.16(B) states anyway. "Control devices in the emergency lighting system shall be listed for use in emergency systems"

Agreed?

 

[tortuga]

This violates my design rule #1 Nothing permanently attached, critical or life safety should be wireless in a good design.
Every wireless device in a building is an open attack surface for a hacker to get into critical systems.
But I bet its 'listed for emergency use', I have seen lots of these systems.
Just a bad design.

 

[Kansas Mountain]

What wireless control system is it? We put Lutron's Vive on schools all the time. If the fixtures have an integral battery pack, they get a standard powpak and operate just like they would in a traditional hard wired installation. If the emergency power source is a generator, there are emergency powpaks that would be used in lieu of standard powpaks. The EM powpaks still get an additional unswitched hot conductor to sense loss of power. The key is to make sure that the Hub IS NOT on an EM power source. The emergency powpaks have a UL924 bypass switch and turn on the fixtures in their zone to 100% output and will ignore any commands from any sensors/switches until normal power has been restored. Once the Hub has it's power restored for a certain amount of time (2 minutes or something, don't remember exactly off the top of my head) and starts resending wireless signals to the powpaks, the EM powpaks will return their associated fixtures to their pre-outage settings. Standard powpaks will still respond to local controls during the outage.

Important to note that at least the Vive system DOES NOT work with a central inverter. The switch from utility to emergency power is too fast and will not trigger emergency mode on the EM powpaks.

 

[Kansas Mountain]

This violates my design rule #1 Nothing permanently attached, critical or life safety should be wireless in a good design.
Every wireless device in a building is an open attack surface for a hacker to get into critical systems.
But I bet its 'listed for emergency use', I have seen lots of these systems.
Just a bad design.

Just FYI, I can't speak for all systems, but Lutron's Vive system does not require a network connection. It generates it's own wifi signal. The Hubs do have RJ45 terminals for network drops that would enable the end user to control the system from remote locations. Some of my clients prioritize network security, others prioritize convenience.