Fuel cell medical center

[hhsting]

Anyone who did or expert at fuel cell. This is Medical center setting. Attached snapshot I have fuel cell connected to MLO main service disconnects switchboard with one of the service breakers at 500A breaker which is connected to fuel cell.

The switchboard is also powered by utility and emergency generator that has critical branch, equipment branch and life safety branch. The cable #1 in snapshot is connected to the fuel cell and fuel cell 500A breaker in MLO main service switchboard.

I looked at NEC 2017 Article 695 but confused. Three questions: 1. Is the fuel cell stand alone system in snapshot? 2. How does one size the 500A breaker and cable #1 connected to the fuel cell snapshot? 3. Does the fuel cell require disconnect or not in snapshot case?

 

[ramsy]

looked at NEC 2017 Article 695 but confused.

Some requirement in 2017 NEC. May be more I missed
700.12(6)(F), 701.12(F), 705.30(C), and 708.20(H)

Three questions: 1. Is the fuel cell stand alone system in snapshot?

Perhaps a Separately Derived System per 517.30(B)(2), which may operate without a neutral, per 200.3 Exception

2. How does one size the 500A breaker and cable #1 connected to the fuel cell snapshot?

692.8(A & B) Equipment Nameplate only, not factory specifications, nor cut sheets

Would also check for the larger of 692.53 nameplate continuous load x 1.25, per 215(A)(1)

3. Does the fuel cell require disconnect or not in snapshot case?

See 230.82(6), and 692 Part VI Marking. May be more I missed

 

[hhsting]

Some requirement in 2017 NEC. May be more I missed
700.12(6)(F), 701.12(F), 705.30(C), and 708.20(H)

Perhaps a Separately Derived System per 517.30(B)(2), which may operate without a neutral, per 200.3 Exception

692.8(A & B) Equipment Nameplate only, not factory specifications, nor cut sheets

Would also check for the larger of 692.53 nameplate continuous load x 1.25, per 215(A)(1)

See 230.82(6), and 692 Part VI Marking. May be more I missed

I dont follow. NEC 2017 Article 700 has to do with fuel cell?

Also i dont follow response #2 which was in the snapshot would the fuel cell is stand alone or not? If you look at snapshot their is already two sources utility and generator.

 

[ramsy]

I dont follow. NEC 2017 Article 700 has to do with fuel cell?

That was 700.12(B)(6)(E)

Also i dont follow response #2 which was in the snapshot would the fuel cell is stand alone or not? If you look at snapshot their is already two sources utility and generator.

Drawing shows Roll Up generator transfer switch to life safety branch only.

Fuel cell drawing shows no transfer switch, or a 692.2 Interactive System tied in with utility, rather than a Stand-Alone System.

Except fuel-cell drawing is missing the inverter, & disconnects.

 

[hhsting]

That was 700.12(B)(6)(E)

Drawing shows Roll Up generator transfer switch to life safety branch only.

Fuel cell drawing shows no transfer switch, or a 692.2 Interactive System tied in with utility, rather than a Stand-Alone System.

Except fuel-cell drawing is missing the inverter, & disconnects.

No all the branches have generator. ATSs show future generator. The snapshot is incomplete drawing being large but their is generator supplying the all ATSs.

So then one cannot figure out if its standalone since their is no transfer switch with utility.

Cannot the inverter be inside all together with fuel cell?

 

[ramsy]

No all the branches have generator. ATSs show future generator.

In post #3, you referred to 2 sources.

If counting EM generator thats 3 sources. Unless upper right side of plan is 4th source.

So then one cannot figure out if its standalone since their is no transfer switch with utility.

If fuel cell branch on load side of service xfmr operates in parallel with utility, its an Interactive System regardless of transfer switch.

Cannot the inverter be inside all together with fuel cell?

IMHO a utility-interactive inverter should be shown separately.

 

[hhsting]

In post #3, you referred to 2 sources.

If counting EM generator thats 3 sources. Unless upper right side of plan is 4th source.

If fuel cell branch on load side of service xfmr operates in parallel with utility, its an Interactive System regardless of transfer switch.

IMHO a utility-interactive inverter should be shown separately.

There are two sources utility and emergency generator that supply all ATSs. I am not talking about roll up generator thats separate.

I am just not sure if the fuel cell count as source that supply building or it is utility interactive that sends power back to utility.

 

[ramsy]

not sure if the fuel cell count as source that supply building or it is utility interactive that sends power back to utility.

Roger that, not enough info.