Rev. 1 - 11/97
EMERGENCY CALL SWITCH
The Alpha Communications® SF118/3B Emergency
Switch is designed for emergency-call systems that need to
interface to a customer supplied smoke detector (form 'C')
relay output, and features a rugged, long-life, positive-
acting switch mounted on a durable ABS plastic faceplate.
Signaling an emergency requires just a short pull on the 6'
long nylon cord, in any direction. The signal cannot be
canceled except at the point of origin.
The SF118/3B provides the circuits to operate signaling
devices, such as a remote annunciator lamp, a corridor
dome lamp, floor bell(s), individual apartment electric
door openers, and smoke detector relay interfaces, as
A unique feature of the SF118/3B series pull cords is that
it has a mechanical indicator window that turns 'Red' when
the pull station is activated. This provides a 'call placed' or
'call assurance' capability without the need for any lamp
indicators, additional power supplies, or additional wiring.
The SF118/3B features a rugged, long-life, positive-acting
switch mounted on a flame retardant type ABS plastic
faceplate marked "EMERGENCY" that includes a red call-
placed LED., with a special diode network to allow for the
smoke detector relay interface.
Height: 4.50" (114mm) (less cord)
Width: 2.75" (70mm)
Depth: 1.50" (38mm) (into wall)
White ABS plastic.
SF118/3B - 4PDT with special diode
network for smoke detector interface
Positive screw terminals
Standard single-gang electrical box
"EMERGENCY" in Black Letters
Mechanical 'Red' window AND Red
call-placed L.E.D. indicator
Refer to system wiring diagram IL514 for more complete
Due to continuous product improvement, all colors, sizes, materials,
finishes and specifications are subject to change without notice.
ARCHITECTS' AND ENGINEERS'
The Emergency Call switch shall be