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These documents will be prepared by the lead engineers for the electrical equipment, such as transformers, motor control centers (MCCs), VFDs, switchgear, etc. Revisions to these documents may follow the same procedures as identified for the drawings. Following a receipt of the tenders from the suppliers, the engineer prepares technical tender evaluations with appropriate conclusions, recommendations, and specific conditions for purchasing the equipment. As part of the award of contract, the specifications and data sheets are updated to match that of what was agreed on “as purchased” (see Chapter 24 for some specification details and data sheets).

A typical small or big project requires a number of specifications with data sheets to be written. The specifications define the equipment performance requirements and workmanship. The data sheets cover the specific equipment rating requirements. The specification for a particular piece of equipment can be updated from project to project with some minor changes. It is the data sheet that changes in a big way as the application and ratings may be completely different from project to project.

Hopefully, the new specifications will be similar to those of your previous projects. Often, one can change the project name and the spec number and then revise the data sheet to suit the equipment you need for your new project. Try not to repeat yourself in the documents. Sooner than you think, someone will call and ask you: “What do you want: 1000 A breaker written in the specification or 1200 A breaker listed in the Data Sheet.” If you want to talk about the breaker in the specification, just note: “For the ratings, refer to the Data Sheet.”

From project to project, try to maintain the same ID number for the same design product, if the project permits it. For instance:

 Specification and data sheet, respectively, for MCCs on project ABC: ABC – xxx – TS31 – DS31

 Specification and data sheet, respectively, for MCCs on project XYZ: XYZ – xxx – TS31 – DS31

Try to group the documents for the type of equipment and services. Leave some gaps as there are differences in scope from project to project. When you are dealing with equipment like MCCs located in various different parts of a plant, write a common spec with several data sheets added to it for different areas.

Here is a list of specifications from a recent project in Minnesota on a 55 MW power plant using turkey litter as fuel:

1 Electrical contribution to mechanical engineers' specifications.

TS01	Electrical requirements for mechanical equipment
TS02	Electrical requirements for 480 V motors up to 200 kW
TS03	Electrical requirements for medium voltage (MV) motors over 200 kW

1 Main power distribution

TS11	Switchyard equipment and hardware
TS13	Large transformers
TS14	Standby diesel generator
TS15	Relay protection panels
TS17	13.8 kV transformers
TS21	13.8 kV switchgear

1 Plant equipment

TS23	MV motor controllers
TS24	MV VFDs
TS31	480 V MCCs
TS32	480 V VFDs
TS33	Unit substations and low voltage (LV) switchgear
TS35	Station battery and chargers
TS36	Uninterruptible power supply (UPS) equipment and panels
TS37	Rigid bus ducts
TS38	Cable bus ducts
TS39	Lighting and distribution panels
TS40	Power and control cables
TS41	Plant heat tracing panels and hardware

1 Services and plant installation

TS43	Plant CCTV
TS44	Plant public address
TS45	Plant telephones and data
TS51	Plant fire detection and suppression system
TS52	Plant heat tracing
TS54	Overhead distribution lines
TS55	Switchyard installation
TS57	Plant installation