emergency shunt relay wiring lighting

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bgelectric

Senior Member
So i have a scenario im confused about.
Plans call to wire 3 out of ten lights to existing life safety circuit.provide emergency shunt relay to bypass local switching. Life safety circuit is obviously on a different circuit than general lighting. I purchased a gr2001 to accomplish this. The diagram for the relay show normal power energizing coil and emergency power going though the contacts in parallel with the switch. How do i accomplish this when the switch is shown drawn in parallel with the emergency power not normal power? Its an existing building with normal power feed ing the lights..
 
T

templdl

Senior Member
Location
Wisconsin
bgelectric said:
So i have a scenario im confused about.
Plans call to wire 3 out of ten lights to existing life safety circuit.provide emergency shunt relay to bypass local switching. Life safety circuit is obviously on a different circuit than general lighting. I purchased a gr2001 to accomplish this. The diagram for the relay show normal power energizing coil and emergency power going though the contacts in parallel with the switch. How do i accomplish this when the switch is shown drawn in parallel with the emergency power not normal power? Its an existing building with normal power feed ing the lights..
Click to expand...

Oops. Did you intend to include a wiring diagram of you proposed circuit?
 
J

JDBrown

Senior Member
Location
California
Occupation
Electrical Engineer
bgelectric said:
So i have a scenario im confused about.
Plans call to wire 3 out of ten lights to existing life safety circuit.provide emergency shunt relay to bypass local switching. Life safety circuit is obviously on a different circuit than general lighting. I purchased a gr2001 to accomplish this. The diagram for the relay show normal power energizing coil and emergency power going though the contacts in parallel with the switch. How do i accomplish this when the switch is shown drawn in parallel with the emergency power not normal power? Its an existing building with normal power feed ing the lights..
Click to expand...
I'm afraid may not quite understand the question, but I'll take a stab at it anyway. ;)

It sounds like you have ten lights - (3) connected to a life safety circuit and (7) connected to a normal circuit. They are switched separately: one switch for the life safety lights, and one or more switches for the normal lights. The switch for the life safety lighting is connected in parallel with the bypass relay's contacts; the relay has nothing to do with the switch(es) for normal lighting. The relay's coil is energized by a normal power circuit -- probably, though not necessarily, the normal lighting circuit. The conductor going to the coil must not be switched (if it were switched, then the life safety lights would come on any time the normal lights were turned off). As long as there is normal power to the coil, the relay's contacts remain open and the life safety light switch functions normally. If power to the bypass relay's coil is lost (e.g. in the event of a power outage), the relay's contacts close and bypass the life safety light switch, thus turning the lights on regardless of the position of the manual switch.

Does this help, or did I completely misunderstand what you were looking for? (It's been known to happen.)
 
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bgelectric

Senior Member
View attachment wiring.pdf
Sorry here is the drawing.
View attachment gr2001.pdf
Here is the relay wiring.
My dilema is that the existing lighting circuit is not in the life safety circuit. The lights which are half darkend are shown to be tied into the life safety circuit and switched via switches shown.
How do I switch the lights Hatched with existing circuit along with putting them on the life safety circuit...?:?
 
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GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
bgelectric said:
View attachment 8819
Sorry here is the drawing.
View attachment 8820
Here is the relay wiring.
My dilema is that the existing lighting circuit is not in the life safety circuit. The lights which are half darkend are shown to be tied into the life safety circuit and switched via switches shown.
How do I switch the lights Hatched with existing circuit along with putting them on the life safety circuit...?:?
Click to expand...

You run new wires to those specific fixtures, possibly in raceways which only carry life safety circuit conductors. And you probably make sure the "normal" switches for those fixtures are in a separate box rather than sharing a multi-gang box with normal circuit switches.
For Health Care Facilities for example, 517.30(C)(1):
(1) Separation from Other Circuits. The life safety branch and critical branch of the emergency system shall be kept entirely independent of all other wiring and equipment and shall not enter the same raceways, boxes, or cabinets with each other or other wiring.
Click to expand...

The term Life Safety system occurs only, AFAIK, in Article 517. But for other uses similar conditions apply based on 700, 701 and 702.

If it were not for energy requirements, it would be much easier to leave them always on.
 
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B

bgelectric

Senior Member
GoldDigger said:
You run new wires to those specific fixtures, possibly in raceways which only carry life safety circuit conductors. And you probably make sure the "normal" switches for those fixtures are in a separate box rather than sharing a multi-gang box with normal circuit switches.
For Health Care Facilities for example, 517.30(C)(1):


The term Life Safety system occurs only, AFAIK, in Article 517. But for other uses similar conditions apply based on 701 and 702.

If it were not for energy requirements, it would be much easier to leave them always on.
Click to expand...

So your saying I need a separate switch for those fixtures indicated life safety?
The plans call for those lights to be on switch C or D off the existing circuit...
Seems to me like there is a conflict in the drawings...
 
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GoldDigger

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Staff member
Location
Placerville, CA, USA
Occupation
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bgelectric said:
So your saying I need a separate switch for those fixtures indicated life safety?
The plans call for those lights to be on switch C or D off the existing circuit...
Seems to me like there is a conflict in the drawings...
Click to expand...
Since they will be, according to the relay drawing, supplied from a different breaker than the normal lights, you cannot have one switch controlling both types unless it is a multi-pole switch. And even then you may be restricted by 700 and 701 in what you are allowed to do. Read carefully.

And I also have a problem with the apparent assignment of control of these lights to switched circuits c and d. One way to get that effect would be to use a more complicated relay configuration than shown. (Such as the one described by masterinbama.)
 
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masterinbama

masterinbama

Senior Member
Location
Huntsville Alabama
wire from your wall switch to your 7 normal lights and the coil on a RIB (Relay In a Box). Use your normal circuit constant hot and neutral to maintain the coil on your shunt relay and parallel your NO's in your RIB with your NC's in your shunt relay. This way your wall switch will bring all of your lights on and your 3 EM's will come on if your shunt relay loses coil power no matter where the wall switch is.
 

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T

templdl

Senior Member
Location
Wisconsin
bgelectric said:
View attachment 8819
Sorry here is the drawing.
View attachment 8820
Here is the relay wiring.
My dilema is that the existing lighting circuit is not in the life safety circuit. The lights which are half darkend are shown to be tied into the life safety circuit and switched via switches shown.
How do I switch the lights Hatched with existing circuit along with putting them on the life safety circuit...?:?
Click to expand...

Great,
Now we're talking.
 
R

ronaldrc

Senior Member
Location
Tennessee
I think this is what they want.




GR 2001 Emergency override.JPG



Ronald :)
 
G

GoldDigger

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Staff member
Location
Placerville, CA, USA
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Retired PV System Designer
ronaldrc said:
Well I was very bored and it was very late.

Thanks : Ronald :)
Click to expand...
For the benefit of those who wonder why they do not see a series circuit in the original post or the quotes of it.
An interesting feature of the way the drawing was linked: Ronald could not edit the post, but he could put a corrected drawing at the same URL which he hosts. So to that extent it is possible to change the content of a post even after the editing period has expired.

Also, just a quibble about the suggestion: the original drawing shows both normal and emergency lights on both switches c and d rather than a neat division between them. This may just be an error in the drawing, or it may be a need to either change the drawing or make the wiring more complex. (Possibly two pole switches as I noted earlier. But two pole switches may not deliver sufficient separation between the two circuits. The relay shown contains a barrier for the inside of the box.)
 
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kwired

kwired

Electron manager
Location
NE Nebraska
GoldDigger said:
For the benefit of those who wonder why they do not see a series circuit in the original post or the quotes of it.
An interesting feature of the way the drawing was linked: Ronald could not edit the post, but he could put a corrected drawing at the same URL which he hosts. So to that extent it is possible to change the content of a post even after the editing period has expired.

Also, just a quibble about the suggestion: the original drawing shows both normal and emergency lights on both switches c and d rather than a neat division between them. This may just be an error in the drawing, or it may be a need to either change the drawing or make the wiring more complex. (Possibly two pole switches as I noted earlier. But two pole switches may not deliver sufficient separation between the two circuits. The relay shown contains a barrier for the inside of the box.)
Click to expand...
2 single pole switches with barrier between them and some kind of handle tie like used for breakers on MWBC's:cool:
 
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