Network Compartment Ventilation Fan

[Grouch1980]

For NYC, where you need a ventilation fan to ventilate the network compartments, for a 460 volt service... is the ventilation fan required to be on its own service switch, or can it connect to a breaker / fuses on the load side of the service equipment?

 

[infinity]

It's usually tapped off of the service conductors to a disconnect switch.

 

[Grouch1980]

It's usually tapped off of the service conductors to a disconnect switch.

When you say disconnect switch, do you mean service switch?

Also, can I just tap out of the buss detail inside the service end box?

 

[infinity]

When you say disconnect switch, do you mean service switch?

Also, can I just tap out of the buss detail inside the service end box?

I believe that on the last one we did it was tapped off of the service switchboard. Let me take a look I may have a photo somewhere.

 

[Grouch1980]

I believe that on the last one we did it was tapped off of the service switchboard. Let me take a look I may have a photo somewhere.

Thank you sir.

And this disconnect switch... is it a service switch, and does it have to be dedicated solely to the ventilation fan?

 

[Grouch1980]

Thank you sir.

And this disconnect switch... is it a service switch, and does it have to be dedicated solely to the ventilation fan?

I see what you did… you tapped off before the service switch at the switchboard, and you go into the fans service switch. The switch feeds a meter (460 volt service, so the meter goes after the switch) the meter feeds the manual transfer switch, and you have the same setup from the other take-off?

 

[infinity]

I see what you did… you tapped off before the service switch at the switchboard, and you go into the fans service switch. The switch feeds a meter (460 volt service, so the meter goes after the switch) the meter feeds the manual transfer switch, and you have the same setup from the other take-off?

We had two 30 amp disconnects each tapped off of a different service feeding a transfer switch which fed the fan. This is one of the switches.

 

[Grouch1980]

We had two 30 amp disconnects each tapped off of a different service feeding a transfer switch which fed the fan.

So the 30 amp switches do not have to be service switches? That’s what I’m trying to follow.

 

[Grouch1980]

I’m also not following where in the switchboard your 30 amp switch tapped from. Load side of the CT, line side of the main service switch?

 

[infinity]

In this case they're ahead of the service on the ConEd side so I'm not sure if you would consider it a service disconnect but would it really matter? Take a look at the photo. You can see the 3/4" RMC entering the crown box where it connects to the bus stabs from the network compartment.

 

[Grouch1980]

In this case they're ahead of the service on the ConEd side so I'm not sure if you would consider it a service disconnect but would it really matter?

That looks like a service switch. Wouldn’t it matter though?… if it’s a service switch, now it has to be grounded.

Take a look at the photo. You can see the 3/4" RMC entering the crown box where it connects to the bus stabs from the network compartment.

Is there a meter on the load side of the switch? How is this metered?

 

[infinity]

Is there a meter on the load side of the switch? How is this metered?

It's on the ConEd side so it is not metered. If the GEC lands upstream of a service switch the switch does not require a separate GEC connection.

 

[Grouch1980]

It's on the ConEd side so it is not metered. If the GEC lands upstream of a service switch the switch does not require a separate GEC connection.

Ok… I believe I’m now following. You’re connecting directly to their service take-off. So the connection is not exactly on the customer side. Do I have that right?

Going off on a tangent… light fixtures in the network compartments… how do you feed those? From a 20 amp breaker on a regular 277/480 volt panel?

 

[infinity]

Ok… I believe I’m now following. You’re connecting directly to their service take-off. So the connection is not exactly on the customer side. Do I have that right?

Correct. That's the way it was done on the job in the photos.

Going off on a tangent… light fixtures in the network compartments… how do you feed those? From a 20 amp breaker on a regular 277/480 volt panel?

I can't remember. I had a set of ConEd network protection drawings but I moved and now I cannot find them.

I'm leaning towards the lights being fed from a tap to a disconnect switch within the vault. If for some reason they had to pull the links to the services the lights in the vault would stay on.

 

[Grouch1980]

I'm leaning towards the lights being fed from a tap to a disconnect switch within the vault. If for some reason they had to pull the links to the services the lights in the vault would stay on.

That would make sense. The ventilation fan and lights are not part of the customer side. So they would be connected to the Con Edison equipment / take-offs.

Would the network compartments and transformer vaults need receptacles? I’m assuming they would connect in the same way as the lights.

Getting these answers from Con Edison is like pulling teeth. I already tried. And when they do respond, they speak in riddles. Their ‘EO’ documentation is a mess.