Help with Power Schematic Acronyms/Labels

[ddspell]

I'm reviewing some documentation that was created years ago. There are some acronyms on a power schematic that I'm unsure what they are.

Please confirm or correct the following:

EHA - 

ELA - 

EMAC - 

EMDP - Emergency Mechanical Distribution Panel

MBS - Maintenance Bypass Switch

MSA - Measurement Systems Analysis? - Not sure if this is the right definition for a power schematic

PDU - Power Distribution Unit

TRSF - Abbreviation for TRanSFer?
TVSS - Transient Voltage Surge Suppressor

On the diagram, MSA is a square attached to a smaller TVSS square. A square labeled BLDG TRSF 1 is connected as input. The MSA leads to the ATS (Automatic Transfer Switch) square which leads to two adjacent EMDP squares. One of the EMDP squares has an arrow going to an EHA square, and an arrow going to a TRSF square that leads to two adjacent ELA squares.

The EHA and ELA squares may be some kind of location acronyms.

There's a bullet list for ELA which lists...
* CSR (Customer Service Reps) Cubes

* Fire Controls

* Guard Shacks

* Emergency Receptacles

EHA's bullet list only has one item for Emergency Lighting