Pad locks for temp construction power placed in handle mechanism vs switch base?

[Dale001289]

For temporary construction power, the electricians placed pad locks in the handle mechanism instead of the hasp at the base of the enclosure.
The switches are NEMA 3R, ranging from 30A to 100A, both fused and non-fused. They are all in the upward, “ON” energized position - not “OFF”.
Won’t this impede the handle movement downward into the “OFF” position if a quick disconnect is required?

 

[infinity]

Won’t this impede the handle movement downward into the “OFF” position if a quick disconnect is required?

Yes it would but where is the ability to quickly disconnect something required? According to the NEC locks do not render the switch as not being readily accessible.

 

[jim dungar]

Won’t this impede the handle movement downward into the “OFF” position if a quick disconnect is required?

Maybe.
Disconnects are not required, by the NEC, to be readily operable for 'quick' operation.

Are these disconnects locked in the On position, or are the locks just placed in a convenient hole?

 

[infinity]

Are these disconnects locked in the On position, or are the locks just placed in a convenient hole?

Sounds like they're locked in the ON or closed position so no one can turn them off without the key.

 

[Dale001289]

Sounds like they're locked in the ON or closed position so no one can turn them off without the key

Yes Infinity, they’re locked in the closed position - I.e., they’re ON.
it seems like the switch operation would be restricted by the padlock if there was an immediate need to open to the OFF position. However as you’ve noted by code definition locks are permitted - so I’m not sure if I should even flag this to the electricians given the fact also this is temp power which we all know, gets ‘abused’ all the time even though it’s supposed to follow NEC

 

[infinity]

Yes Infinity, they’re locked in the closed position - I.e., they’re ON.
it seems like the switch operation would be restricted by the padlock if there was an immediate need to open to the OFF position. However as you’ve noted by code definition locks are permitted - so I’m not sure if I should even flag this to the electricians given the fact also this is temp power which we all know, gets ‘abused’ all the time even though it’s supposed to follow NEC

There is no NEC issue with what you've described. The locks serve a purpose otherwise the electricians wouldn't install them. Unless you can cite some other code or standard IMO there is nothing to flag.

 

[Dale001289]

There is no NEC issue with what you've described. The locks serve a purpose otherwise the electricians wouldn't install them. Unless you can cite some other code or standard IMO there is nothing to flag.

Yes these locks would be used for LOTO.
I’d vastly prefer to see them ‘installed’ in the hasp at the base of the enclosure where there is no interference with the On/Off action of the handle
but I can’t enforce it if there’s no NEC issue

 

[jim dungar]

I’d vastly prefer to see them ‘installed’ in the hasp at the base of the enclosure where there is no interference with the On/Off action of the handle

There is a difference between locking an enclosure to prevent opening and locking the disconnect in the closed (On) position.

 

[retirede]

We had some equipment that you could really mess up if the control system’s shutdown sequence wasn’t allowed to complete. We had those disconnects locked in the “On” position.

 

[Dale001289]

We had some equipment that you could really mess up if the control system’s shutdown sequence wasn’t allowed to complete. We had those disconnects locked in the “On” position.

In this case it’s just temp Power

 

[Dale001289]

There is a difference between locking an enclosure to prevent opening and locking the disconnect in the closed (On) position.

Agreed but I don’t think in either case it would be considered a code violation

 

[jim dungar]

In this case it’s just temp Power

But what if the temp power was running fans for ventilation or humidity removal? I can think of many reasons to lock it on.

In a true emergency how long would it take to locate, get to, and operate this disconnect even if it is not locked?
For LOTO, the disconnect needs to be turned off. In this case removing a lock is just one more step in the procedure.

 

[Dale001289]

But what if the temp power was running fans for ventilation or humidity removal? I can think of many reasons to lock it on.

In a true emergency how long would it take to locate, get to, and operate this disconnect even if it is not locked?
For LOTO, the disconnect needs to be turned off. In this case removing a lock is just one more step in the procedure.

All of these disconnects are non-critical in nature. They also have several temp power Panelboards locked up with padlocks - the superintendent has the key but it would take him at least 20 Minutes to reach the circuit breakers in an emergency scenario.
Here again, if I can’t enforce it with NEC it’s pretty much a moot point.

 

[jim dungar]

Here again, if I can’t enforce it with NEC it’s pretty much a moot point.

The NEC is about installation safety. You need to look at other codes like OSHA and NFPA70E for operational safety.

 

[infinity]

In this case it’s just temp Power

In many places the electrician controls the temporary power. The installation and maintenance of the temp power is under the electricians license so it's not unreasonable for them to use locks on disconnect switches. The company I worked for had several lawsuits all from injuries that were allegedly caused by the temporary power and lighting.