Specifications

PIP ELCGL01
Electrical Design Criteria November 2002
Page 16 of 20 Process Industry Practices
10.3 Specialty Receptacles
Receptacles for use at voltages other than nominal 120 or 480 volts shall be selected
according the application.
11. Wiring Methods
11.1 Cable Tray
11.1.1 Cable tray shall be heavy-duty-rated NEMA 20C and NRTL-listed and shall
be labeled as an equipment-grounding conductor unless specified otherwise
on the Data Sheet. The cable tray shall be secured with clips at every
support. The tray shall be sized for a minimum of 20% spare after
completion of project unless specified otherwise on the Data Sheet. Unless
specified otherwise on the Data Sheet, the tray shall be of the ladder type
with 9-inch rung spacing suitable for indoor or outdoor installations. The
cable tray shall have a minimum load safety factor of 1.5 based on the load
capacity as defined in NEMA VE1. The tray shall also be capable of a
200-pound static load located at mid-span. All bolts, nuts, and washers for
metallic trays shall be stainless steel. All bolts, nuts, and washers for use
with fiberglass tray systems shall be fiberglass.
11.1.2 Expansion joints shall be provided as required by NEMA VE1, Table 6-1, for
long, straight tray runs.
11.1.3 Cable tray shall be installed to allow a minimum of 12 inches of access
above the top of each tray.
11.1.4 Installation of cables in cable trays shall be in accordance with the NEC.
11.1.5 Cable tray systems shall be installed above or to the side of process lines
where possible and at least 12 inches from steam lines.
11.1.6 Cable trays shall not have covers unless specified otherwise on the Data
Sheet.
11.1.7 Separate trays shall be provided for each voltage class of cables unless
specified otherwise on the Data Sheet.
11.2 Aboveground Conduit and Fittings
11.2.1 Acceptable sizes, material, and construction of conduit systems shall be as
identified on the Data Sheet.
11.2.2 When specified on the Data Sheet, electrical metallic tubing (EMT) may be
used in indoor unclassified locations where the EMT will not be subject to
vibration, corrosion, or physical damage (e.g., office buildings,
administration buildings, guardhouses, change houses, etc.).
11.2.3 Flexible conduit shall be liquid-tight and suitable for the area classification
in which it is installed. Flexible conduit shall be used to connect vibrating
equipment to the conduit system. Flexible conduit shall be no more than
3 feet in length.