Montgomery County                           2821

(b)     Connect to source normally "ON". The fire alarm system
shall be connected to a source of electric current which is normally
"ON" at all times and not "switched" except by the service or meter
equipment.

(c)    Supplied through transformer. When the source of
supply for a fire alarm system is through a transformer, even though
low voltage, the wiring method and manner of installation shall con-
form to the provisions of this Article.

(d)    Voltage. Fire alarm circuits shall be operated at not
more than 125 volts.

83-42. Wiring method.

Rigid conduit or electrical metallic tubing shall be the wiring
method employed, except that armored cable may be used for con-
cealed finished work by special permission in existing buildings.

(a)    Hazardous locations. Wiring method and fire alarm
equipment to be installed in a hazardous location shall be subject
to special approval by the Director.

(b)     Outlets. Outlet and junction boxes on exposed work shall
be provided with threaded hubs.

(c)    Separate conduits. Fire alarm conductors or circuits
and associated annunciator wires shall not be installed in the same
outlet box, junction box, conduit, raceway, or armor, with conductors
of any other signal, light, or power system.

(d)     Conduits and conductors in elevator hoistways, etc., pro-
hibited. Fire alarm conduits, cables or conductors supplying, or a
part of, a fire alarm system shall not be installed in any flue, heating
or ventilating duct, incinerator, trash chute, garbage chute, laundry
chute, dumbwaiter, lift, elevator, or similar shaft, nor in any trash or
baling room, except for the connection of an automatic fire detector
located in such trash or baling room.

(e)    Separate circuits. Fire alarm circuits shall not supply
any lights, apparatus, or appliances not essential to, nor a part of, the
fire alarm equipment. No manual control device or switch shall be
inserted in a circuit or feeder serving a fire alarm system other
than the disconnecting means at the service or on the control panel
of a special current source.

(f)     Conductors. Conductors shall be not smaller than No. 14
and be of a type approved for general use. For more than nine con-
ductors in one conduit or tubing, Tables 1 and 3 will apply.

(g)    Overcurrent protection. Overcurrent protection shall
conform to the following: