Rev. 13 November 1, 2016
Page | 73a. All wire and cable for power, lighting, control and signal circuits shall have copper conductors and shall be
insulated to 600 volts. Conductor sizes #12 AWG and smaller shall be solid; conductor sizes #10 AWG and
larger shall be stranded. All standard building wiring shall be THWN/THHN. Aluminum conductors are not
allowed.
b. In-line splices and taps for conductor sizes #8 AWG and smaller, shall use vinyl insulated spring connectors.
Connectors for conductors sizes #6 and larger shall be compression lug types.
c. Conductor identification-all circuits originating from 20 amp circuit breakers shall have the grounded
conductor identified by a colored tracer of the same color as the ungrounded conductor.
d. Color code conductors as follows:
i. 120/208V, 3PH, 4W: Phase A – Black; Phase B – Red; Phase C – Blue; Neutral – White; Ground –
Green.
ii. 277/480V, 3PH, 4W: Phase A – Brown; Phase B – Orange; Phase C – Yellow; Neutral – Grey;
Ground – Green.- Installation
a. All cable for major feeders shall be continuous from origin to termination. Splices in branch circuit wires
shall be made only in accessible junction boxes. Keep conductor splices to a minimum.
b. All po wer feeder cable shall be pulled with the use of approved pulling compound or powde r. Pull all
conductors into raceway at the same time.
c. Neatly arrange, label, and tie-wrap all wiring inside all cabine ts, pa nelboards, boxes, and other e nclos ur es.
26 05 26 Grounding and Bonding for Electrical Systems- General
a. All equi pment, lighting, devices, and metallic conduit systems shall be grounded per NEC 250, NEC 517,
and NFPA 99.
b. Maximum resistance of main service g rounds shall be 3 ohms.
c. In ne w service applications, the main electrical service ground shall be connected to the incoming water
service, a ne w grounding gr id, bu ildi ng steel, and steel reba r in the f oundations.
d. The grounding grid shall consist of ground rods spaced 10’-0” apa rt, connected with exothe rmic welds, in
addition to c on ductors installed in the transformer vault w alls. Coordinate m ain g rounding with t he Electrical
Distribution Department.
e. In the olde r portions of the facility (Boyd Tower, Gene ral Hospital, and South Wing), a sepa rate grounding
conductor is not always present in feeders and branch circuits. I n remodel projects w here existing panels are
reused, proper g rounding of that panel shall be obtained by bonding t he feeder conduit serving the panel at the
pa nel, all p ul l boxes, a nd the source pane l; or by r e-pulling a new f eeder with a sepa rate g rounding conductor
if the panel will serve sens iti ve electronic or diagnostic equipment. Branch circuit wiring with no grounding
conductor shall not be reused f or new circui ts.
f. Where ne w panels are adde d, the feeders to the source panel shall cont ain a grounding conductor.
The sou rce panel s hall be prope rly grounded back to the m ain electrical service if pr oper g rounding does not
cur rently exist.
g. A grounding electrode conductor shall be extended to all step-down transformers from the main
electrical service ground ba r. This shall be used to ground the seconda ry ne ut ral. The equipment
grounding conductor is NOT t he grounding electrode.
h. Isolated g round panels shall be used in a reas w ith sensitive equipment such as electronics, h ospital di agnostic
equipment, and computer equipment. A separate isolated grounding conductor (green with a yellow