We have a disconnect ( 30 amp ) that feeds a small motor starter in a separate enclosure just below the disconnect . It has a indicator lamp to show when the motor is running . If a maintenance person is giving a WR to replace the indicator lamp or work on the start / stop control is a lock required on the disconnect just above it ???
As noted by others, you are missing some key details here. But if we make the assumption that the Pilot devices are in the cover of the motor starter (as per usual), there are still two more levels of your question:
... to replace the indicator lamp". If by that, you mean the bulb only, that depends on the style of indicators involved. Many can be replaced by unscrewing the lens from the outside and swapping out the bulb, never exposing the worker to line voltage potential. Those would be fine without locking out the disconnect.
If they have the type that requires access to the back side of the pilot light to be able to change it, and/or they are going to "...
work on the start / stop control .."which also means removing the starter cover, then they will be exposed to line voltage potential as well as whatever Arc Flash energy exists in the starter box if the disconnect is not open BEFORE the starter is opened. So for sure that will require the disconnect to be off, or for the electrician to suit up in the appropriate PPE and likely obtain a "Hot Work Permit" through whatever safety process the employer or owner has in place. If there is no process in place, that alone is an OSHA violation, potentially criminal for the managers/supervisors!
If what you meant was "the disconnect will be opened, but must he LOCK it open (LO/TO)?", that's not as clear given that they will be performing work right there. The problem with NOT locking it is that it then opens the issue for the electricians to "interpret" the rules; "Sometimes we lock it, sometimes we don't..." Having a procedure stating that the disconnect must ALWAYS be locked when working on something powered by electricity leads to people staying in the habit of it and working safely. That's a better plan in my opinion.
