Handle tie hospital emergency circuit

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It appears to be an unintentional loop hole in the code. Receptacles on the same yoke have to have a common disconnect if there is more than one cicuit feeling it. I have seen where mutiwires branch circuits are forbidden in patients rooms because of the reason of turning off more than one circuit and all emergency circuits are forbidden from having shared neutrals too.

Is there a code to forbid handle ties for receptacles in patient rooms, because it defeats the intent of the code to for the common disco for hospitals and e circuits?
 

roger

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It appears to be an unintentional loop hole in the code. Receptacles on the same yoke have to have a common disconnect if there is more than one cicuit feeling it. I have seen where mutiwires branch circuits are forbidden in patients rooms because of the reason of turning off more than one circuit and all emergency circuits are forbidden from having shared neutrals too.

Is there a code to forbid handle ties for receptacles in patient rooms, because it defeats the intent of the code to for the common disco for hospitals and e circuits?

The reason the ROP (15-45 Log #1504 NEC-P15 ) was submitted was not for items in the same room being affected but the possibility of the MWBC serving other rooms.

In the case of multiple circuits on a single yoke the equipment would be in one room.

Roger
 
The reason the ROP (15-45 Log #1504 NEC-P15 ) was submitted was not for items in the same room being affected but the possibility of the MWBC serving other rooms.

In the case of multiple circuits on a single yoke the equipment would be in one room.

Roger

It was also the intent of limiting the risk and effects of the loss of power In patient rooms. If one circuit was tripped/shut off, it should not affect the other circuits in a patients rooms, both the same room and different rooms. This was to help reduce risk. Imagine a heart monitor or regulator plug into the top receptacle and a lung machine in the lower receptacle. A short happens on the top receptacle, in which it has the potential to take out the bottom receptacle because of the handle tie.

This is not a good design and should be prohibited.
 

mbrooke

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It was also the intent of limiting the risk and effects of the loss of power In patient rooms. If one circuit was tripped/shut off, it should not affect the other circuits in a patients rooms, both the same room and different rooms. This was to help reduce risk. Imagine a heart monitor or regulator plug into the top receptacle and a lung machine in the lower receptacle. A short happens on the top receptacle, in which it has the potential to take out the bottom receptacle because of the handle tie.

This is not a good design and should be prohibited.

Handle tie does not give common trip, so it will (usually;)) not take out the other pole.

IMO the biggest risk would be an open neutral. It would not look good when 3 times the equipment is effected while 1,2 or even 3 thirds of everything is damaged.
 

GoldDigger

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Handle tie does not give common trip, so it will (usually;)) not take out the other pole.

IMO the biggest risk would be an open neutral. It would not look good when 3 times the equipment is effected while 1,2 or even 3 thirds of everything is damaged.
But a handle tie does require you to turn off the second circuit momentarily to reset a trip on the first.
 

roger

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It was also the intent of limiting the risk and effects of the loss of power In patient rooms.
Did you read the ROP?

If one circuit was tripped/shut off, it should not affect the other circuits in a patients rooms, both the same room and different rooms.
And I agree with that.

Imagine a heart monitor or regulator plug into the top receptacle and a lung machine in the lower receptacle. A short happens on the top receptacle, in which it has the potential to take out the bottom receptacle because of the handle tie.
See Iwire's post

This is not a good design and should be prohibited.
Submit a PI for the 20 cycle.

Roger
 
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roger

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It was also the intent of limiting the risk and effects of the loss of power In patient rooms. If one circuit was tripped/shut off, it should not affect the other circuits in a patients rooms, both the same room and different rooms.

Here is the ROP I mentioned for prohibiting MWBC's in patient bed locations.


15-45 Log #1504 NEC-P15 Final Action: Accept(517.18(A) and 517.19(A))

Submitter:
Patrick J. Clancy, Clancy ElectricRecommendation:
Add new second paragraph to read as follows: 517.18(A) & 517.19(A): The branch circuit serving patient bed locationsshall not be part of a multi-wire branch circuit.

Substantiation:
The reason is because of the new requirements in 210.4 that required handle ties or 2 or 3 pole breakers to be used. This will cause more than one patient room to lose power. A problem that one room can shut off other patient room equipment, which will cause patients to not get the treatment needed. There are some pieces of equipment that operate from batteries, but the batteries have failed at times. The time it takes for a nurse to get to three could cause the patient to be injured or die.
Panel Meeting Action: Accept
Number Eligible to Vote: 12
Ballot Results: Affirmative: 11
Ballot Not Returned: 1 Lau, L.

Roger
 
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