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Unformatted text preview: tically and
immediately upon the failure of the normal supply.
12.17 Emergency circuit wiring shall be kept entirely independent of all other wiring and
equipment and shall not enter the same-raceway, box or cabinet with other wiring except:
a) In transfer switches, or
b) In exit or emergency lighting fixtures supplied from two (2) sources. 12.18 The switches installed in emergency lighting circuits shall be so arranged that only
authorized persons have control of emergency lighting, except:
a) Where two or more single throw switches are connected in parallel to control a single
circuit, at least one of those switches shall be accessible only to authorized persons.
b) Additional switches which act only to put emergency lights into operation but not to
disconnect them may be permitted.
Switches connected in series and three-and four-way switches shall not be allowed. 12.19 All manual switches for controlling emergency circuits shall be located at the most
accessible place to authorized persons responsible for their actuation. In places of
assembly, such as theaters, a switch for controlling emergency lighting systems shall be
located in the lobby or at a place conveniently accessible therefrom.
In no case shall a control switch for emergency lighting in a theater for motion picture
projection be placed in the projection booth or on the stage. However, where multiple
switches are provided, one such switch may be installed in such locations and so arranged
that it can energize but not disconnect for the circuit. 12.20 Lights on the exterior of the building which are not required for illumination when there
is sufficient daylight may be controlled by an automatic light-actuated device approved
for the purpose.
12.21 In hospital corridors, switching arrangements to transfer corridor lighting in patient areas
of hospitals from overhead fixtures to fixtures designed to provide night lighting may be
permitted, provided that the switching system is so designed that switches can only select
between two sets of fixtures but cannot extinguish both sets at the same time. 12.22 The branch-circuits over current devices in emergency circuits shall be accessible to
authorized person only. 12.23 Where permitted by the authority having jurisdiction, in lieu of other methods specified
elsewhere in this Section, individual unit equipment for emergency illumination shall
b) Battery charging means, when a storage battery is used.
c) One or more lamps, and
d) A relying device arranged to energize the lamps automatically upon failure of the
normal supply to the building. Unit equipment shall be permanently fixed in place (i.e. not portable) and shall have all
wiring to each unit installed in accordance with the requirements of any of the wiring methods discussed in Chapter II of the PEC. They shall not be connected by flexible
cord. The supply circuit between the unit equipment and the service, the feeders or the
branch circuit wiring shall be instal...
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- Fall '12