Elevator Shunt trip power circuit

[brother]

We have always had a seperate circuit for the power to the shunt trip for the breaker that supplied the elevator. I have seen where someone has tapped into this same circuit to supply other equipment.

Is it not required for the elevator shunt trip circuit to be on its on seperate circuit since it is to be monitored by the fire alarm system? I have looked at NEC 2020 620 and do not see it there. I am not sure if it is in the NFPA 72.

 

[gadfly56]

We have always had a seperate circuit for the power to the shunt trip for the breaker that supplied the elevator. I have seen where someone has tapped into this same circuit to supply other equipment.

Is it not required for the elevator shunt trip circuit to be on its on seperate circuit since it is to be monitored by the fire alarm system? I have looked at NEC 2020 620 and do not see it there. I am not sure if it is in the NFPA 72.

Offhand, I'm not aware of anything in NFPA 72 that requires the circuit powering the shunt coil to be dedicated to that function. It must be monitored, however. The easiest way to do that is to use a System Sensor EOLR-1 to sense the presence of the circuit voltage, and then use an addressable monitor module to monitor the change of state of the EOLR-1 if the supply voltage goes away.

 

[brother]

Offhand, I'm not aware of anything in NFPA 72 that requires the circuit powering the shunt coil to be dedicated to that function. It must be monitored, however. The easiest way to do that is to use a System Sensor EOLR-1 to sense the presence of the circuit voltage, and then use an addressable monitor module to monitor the change of state of the EOLR-1 if the supply voltage goes away.

do you know if the control power that powers the shunt trip is suppose to disconnect after the shutrip breaker is activated and disconnected power?
It was my understanding that it was not suppose to do that, but a fire tech is claiming it is. I have yet to see a code that states that.

 

[GoldDigger]

do you know if the control power that powers the shunt trip is suppose to disconnect after the shutrip breaker is activated and disconnected power?
It was my understanding that it was not suppose to do that, but a fire tech is claiming it is. I have yet to see a code that states that.

It is common for the coil of a shunt trip breaker to be designed for momentary energization only, and to burn out if energized for an extended time after the trip. The simplest way to ensure this is to drive the shunt trip coil via a switched connection to the output side of the breaker (either directly or via a transformer.

 

[brother]

It is common for the coil of a shunt trip breaker to be designed for momentary energization only, and to burn out if energized for an extended time after the trip. The simplest way to ensure this is to drive the shunt trip coil via a switched connection to the output side of the breaker (either directly or via a transformer.

Let me clarify what I am trying ask/say. Im aware that the its momentary to energize the coil on the breaker for the shunt trip breaker to power it off and disconnect main power to the elevator car. I was asking about the 20 amp circuit that powers the control from the smoke head activation. Is this circuit is suppose to go off as well after it has activated? This would mean the power indicator light ( that monitors the control power) is no longer on.

I hope clarified what I am asking.

 

[gadfly56]

Let me clarify what I am trying ask/say. Im aware that the its momentary to energize the coil on the breaker for the shunt trip breaker to power it off and disconnect main power to the elevator car. I was asking about the 20 amp circuit that powers the control from the smoke head activation. Is this circuit is suppose to go off as well after it has activated? This would mean the power indicator light ( that monitors the control power) is no longer on.

I hope clarified what I am asking.

You want to know if the fire alarm control panel circuit breaker should trip out on elevator shunt???

Maybe a step-by-step description is in order. The elevator shunt should not be directly controlled from a smoke detector. Certainly not from a smoke alarm.