Fire Pump Feeder with temporary generator

[philly]

I'm looking at a design for a new 208V Switchboard that has a single utility service and a breaker allocation for a temporary roll-up generator if there is ever a prolonged utility outage. The generator breaker will be interlocked with the utility main breaker.

A fire pump is being required at this site and I am trying to determine if this needs to be fed in the event that the system is operating off the temporary generator?

With just the single utility feed I know that you simply tap the utility service on the load side of the metering point (ahead of service disconnect) and run a feeder straight to the fire pump with a disconnect at the fire pump. If there is a permanent generator installed then there is usually an listed Fire Pump ATS at the fire pump which has feeds from both the utility service and the generator.

But what about in the case where the generator is a temporary roll-up generator that does not currently exist but has a provision? Does the fire pump need to be able to be fed from this generator or does it only need to be fed from the utility service since the generator is not a permanent installation?

 

[iwire]

Have you looked at 695.3? Specifically (A).

It strikes me that if provisions for a roll up generator are needed it would be hard to argue the utility source is reliable.

 

[gadfly56]

Have you looked at 695.3? Specifically (A).

It strikes me that if provisions for a roll up generator are needed it would be hard to argue the utility source is reliable.

"Reliable" is another one of those unfortunate terms in the code, like "workmanlike". The article leaves it up to the AHJ to decide if the power source is reliable.

In any event, it could be that someone merely wants a "belt and suspenders" configuration or maybe they've had a previous bad experience and are working from the precautionary principle.

 

[ron]

Some jurisdictions (NYC for example) require that if you are putting in a 702 generator (which your roll up would be IMHO), that it comply with 700 requirements and pickup the fire pump automatically.

 

[iwire]

"Reliable" is another one of those unfortunate terms in the code, like "workmanlike". The article leaves it up to the AHJ to decide if the power source is reliable.

I agree 100%

However how can you tell the AHJ the supply is reliable but I have generator connections available in case it is not?

I have a hard time seeing that fly.

 

[steve66]

If the fire pump isn't powered, how can anyone safely occupy the building?

If nobody can safely occupy the building, what's the point in having an temp. generator?

 

[gadfly56]

I agree 100%

However how can you tell the AHJ the supply is reliable but I have generator connections available in case it is not?

I have a hard time seeing that fly.

Suppose I know that the POCO plans an outage a couple years down the road to do substation work, or I anticipate I'll need a new transformer some day soon because my company is growing? What if I'm in a tornado area? My power is reliable as long as the poles are up, but every three years I can pretty much count on an outage.

The fact that they want to make provisions for a roll up generator suggests that any outages are likely to be rare enough that they can't economically justify an on-site unit.

 

[iwire]

Suppose I know that the POCO plans an outage a couple years down the road to do substation work, or I anticipate I'll need a new transformer some day soon because my company is growing? What if I'm in a tornado area? My power is reliable as long as the poles are up, but every three years I can pretty much count on an outage.

If it is a tornado area I would call the utility unreliable.

The fact that they want to make provisions for a roll up generator suggests that any outages are likely to be rare enough that they can't economically justify an on-site unit.

So the fact the customer is short on funds changes the rules?

And what about Steve's point?

 

[gadfly56]

If it is a tornado area I would call the utility unreliable.



So the fact the customer is short on funds changes the rules?

And what about Steve's point?

So every property in the world that has a generator, ipso facto, has an unreliable utility source? And if it doesn't have a generator you think it's fine? We're going to have to agree to disagree on this.

What about Steve's point? Perhaps I should have first indicated that yes, if he has a generator on site it needs to be able to pick up the fire pump load. And further, he might not be able to tap after the meter. It has to be on the line side if pulling the meter would remove power from the building.

 

[iwire]

So every property in the world that has a generator, ipso facto, has an unreliable utility source?

See post 4, it is like you pointed out entirely up to the AHJ.

And if it doesn't have a generator you think it's fine?

Can you point to where I indicated that?

We're going to have to agree to disagree on this.

That's fine.

Perhaps I should have first indicated that yes, if he has a generator on site it needs to be able to pick up the fire pump load.

Now this leaves me confused as it seems contrary to your previous posts.

 

[ron]

Perhaps I should have first indicated that yes, if he has a generator on site it needs to be able to pick up the fire pump load.

I'm not a supporter of this (if you mean a 702 application gen needs to pick up the fire pump). In NYC, I have clients that may want a small generator to pickup some small 702 loads, but to pickup a fire pump as required by that local code, the generator has to grow by 10 times.

 

[steve66]

I'm not a supporter of this (if you mean a 702 application gen needs to pick up the fire pump). In NYC, I have clients that may want a small generator to pickup some small 702 loads, but to pickup a fire pump as required by that local code, the generator has to grow by 10 times.

That makes sense, and if it were my call, I would probably say that's fine if the generator powers computers equipment, heating equipment to prevent freezing, or other necessary loads.

On the other hand, if the idea is to power workstations and lights so people can remain in the building, then I'd say that's a different story. There are also fire pumps with diesel motor backup, and that might be a little more cost effective way to cover utility outages.

 

[iwire]

That makes sense, and if it were my call, I would probably say that's fine if the generator powers computers equipment, heating equipment to prevent freezing, or other necessary loads.

On the other hand, if the idea is to power workstations and lights so people can remain in the building, then I'd say that's a different story. There are also fire pumps with diesel motor backup, and that might be a little more cost effective way to cover utility outages.

I agree as well

 

[jim dungar]

It strikes me that if provisions for a roll up generator are needed it would be hard to argue the utility source is reliable.

If your facility is required to have two sources of power, like a hospital, and 1 of them is lost due to a natural disaster, like a hurricane, then normal operations must be suspended. What if no new surgical operations could be started while the facility is being powered by only a single source. A roll-up generator simply restores a two source condition.

I believe the 'non-permanent' generator does not need to pickup the entire facility, although most of the connections I have designed have been equal to the service size.

If the facility is being occupied, I would expect that the Fire Pump needs to be powered.