Is it a violation of modern electrical standards for this lock to be on the circuit breaker handle for the heating system? Who makes the lock, and does Siemens approve of it?
Siemens does. It’s called a lock-off. It’s also upside down. When you flip it over, that prevents the breaker from being flipped because it’s down between the handle and the breaker body.
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No it is not a violation because a circuit breaker will still trip even if the handle is locked in the closed position. There are sections of the NEC that actually require the circuit breaker to be locked in the closed position. As Mark stated it’s not installed correctly.
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I now see how the lock-off is installed upside down. Thank you, @mroberts21 .
Why would anyone want to lock the breaker handle in place? Isn’t that a safety hazard? Shouldn’t we want the circuit to trip when it gets shorted in order to prevent a fire from occurring?
As I stated originally the circuit breaker will still trip even if locked in the on/closed position. Holding or locking the breaker handle will not stop it from tripping. A locking device is required by the NEC when you don’t want someone to inadvertently shutoff or open the breaker. Here’s an example:
700.12(I)(2)(3) The branch circuit feeding the unit equipment shall be one of the following:
a. The same branch circuit as that serving the normal lighting in the area and connected ahead of any local switches
b. Where the normal lighting circuit is served by one or more branch circuits, a separate branch circuit, provided with a lock-on feature, that originates from the same panelboard as the normal lighting circuits. The branch circuit disconnecting means for this branch circuit shall be provided with a lock-on feature.
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That’s interesting that people are claiming that the circuit breaker can still trip with the lock-on feature on there. You are more trusting of the component than I am. If It was my home I might have trouble trusting the circuit to trip with that lock on there. Now I understand what you are saying. Does that code apply to this circuit since it is only for a heating system blower and heat coil, and not for “normal lighting”? Thanks Robert!
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Good question. No it would not be required for this branch circuit. I only posted the code section to show that it can be required.
Robert, I think the OP is saying the circuit in his case is for a heating system. I’m thinking it is possible the lockout is in lieu of a service disconnect at the heating equipment.
It’s possible but what is shown in the photo is not a lock out it’s a lock-on device.
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I’m not familiar with this particular device, but can it not be reversed to lock off?
It could but in order for it to qualify as a lock out device (used in lieu of a disconnecting means) it would require provisions for a lock to be installed.
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Good point!
The OP may want to confirm if there is a service disconnect at the heating equipment, as that might change the narrative of his callout. If no disconnect, than the callout becomes “improper lockout device on heating equipment circuit breaker.” (Possibly, just throwing it out there as something to check).
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Unless the breaker panel is within sight of the heating equipment, than there is no service disconnect required at the heating unit, the breaker panel is compliant.
Note: a Service Disconnect is not required to have or act as a Lockout device!
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That’s why I added…
Not enough info to know at this point, just trying to figure out why someone might have the device on that circuit. 
Yeah, the lock on device is in the event the POCO tries to turn off the power for non payment. 
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Good point. One would hope that an HI would automatically check for a disconnecting means at the heating equipment. 
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The circuit breaker in the panel was the only means of disconnect for the heating system. The circuit breaker would have been within sight of the heating system if wasn’t for a door.
Then in my opinion, you have an improper lockout device. Whether installed correctly or not, it apparently is still improper as you cannot attach a lock to it. I figured there was a reason it was on that circuit, they just didn’t know all the “details” about what was needed, lol.
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