Shown is a fire alarm system connected to a general purpose receptacle in an electrical room with MC cable and a plug. This installation does not meet code and is a dangerous installation for both the electrical safety and for the life safety of the building occupants.
The installation violates the National Electrical Code, NFPA 70, 2005 edition. In addition to the cable not be supporting properly, I question if the installation meets article 330.12. In this article it states that MC cable shall not be installed where subject to physical damage. This was located in an electrical/storage room, where in my opinion would be subject to physical damage. Also, the installation violates 330.40 because the plug is not listed and identified for use with MC cable.
This installation also violates NFPA 72-2002, National Fire Alarm Code. Section 184.108.40.206.1 requires that the fire alarm system shall be connected to a dedicated branch circuit. The receptacle shown was connected to other receptacles in this same room. Also, Section 220.127.116.11.2.1 requires mechanical protection for the branch circuits and connections. As you can see there is no mechanical protection for the plug/receptacle. Also the branch circuits feeding the receptacles were not protected with a handle clamp to lock the breaker in the on position.
John E. Hudacek, PE, CET NICET Fire Alarm Systems Level II Electrical Engineer
Fire alarm panels here are normally hard-wired to their appropriate branch circuit.
Leaving the MC cable and specific code provisions aside, if this were going to be plug-and-receptacle connected I would have thought that a receptacle mounted right next to the panel would be the best approach.