With that said the answer is yes Right?
550.32 Service Equipment.
(A) Mobile Home Service Equipment. The mobile home service equipment shall be located adjacent to the mobile home and not mounted in or on the mobile home. The service equipment shall be located in sight from and not more than 9.0 m (30 ft) from the exterior wall of the mobile home it serves. The service equipment shall be permitted to be located elsewhere on the premises, provided that a disconnecting means suitable for use as service equipment is located within sight from and not more than 9.0 m (30 ft) from the exterior wall of the mobile home it serves and is rated not less than that required for service equipment per 550.32(C). Grounding at the disconnecting means shall be in accordance with 250.32.
They do not come with the disconnect attached around here. Around here job trailers are not required to be tied down (temp structures) so it depends on it its a mobile home or if its a manufactured home not being tied down
550.4 General Requirements.
(A) Mobile Home Not Intended as a Dwelling Unit. A mobile home not intended as a dwelling unit ? for example, those equipped for sleeping purposes only, contractor?s on-site offices, construction job dormitories, mobile studio dressing rooms, banks, clinics, mobile stores, or intended for the display or demonstration of merchandise or machinery ? shall not be required to meet the provisions of this article pertaining to the number or capacity of circuits required. It shall, however, meet all other applicable requirements of this article if provided with an electrical installation intended to be energized from a 120-volt or 120/240-volt ac power supply system. Where different voltage is required by either design or available power supply system, adjustment shall be made in accordance with other articles and sections for the voltage used.
Perhaps my eyes or my brain are not focusing this morning, but I seemed to have missed two points from the OP.
We are quoting Art 550, but is the "temporary trailer" a dwelling unit.550 only applies to dwelling trailers, I believe.
Secondly, are we talking about the panel being used as a utility service disconnect or is it a sub panel. If the utility is involved, most all POCOs that I know of won't feed a mobile structure directly.
I would say NO if it is a trailer or mobile home-- read 550.32
Would this apply if it was a feeder from another panel as on a large construction site?
Would this apply if it was a feeder from another panel as on a large construction site?
Does it really matter if it is a dwelling, construction office, temporary classroom/meeting room, it still must be fed by a feeder and not with a service attached to the structure.
550.4 A relieves the dwelling unit "provisions of this article pertaining to the number or capacity of circuits" requirements but otherwise all other requirements of 550 apply.
Poco will not land on anything with Wheels on it. Disconect on a pole then to the trailer. Office, dwelling or otherwise.