Figure 9-18.--IC/SM-50 alarm switchboard with 10 active modules in place.

Figure 9-18.--IC/SM-50 alarm switchboard with 10 active modules in place.

AUDIBLE VOLUME CONTROL.-- T h e

indicate an existing alarm condition. This switch is

audible volume control is used to adjust the volume of

normally left in the AUDIBLE position.

the speaker.

ALARM SILENCE INDICATOR.-- The alarm

silence indicator illuminates when the visual-audible

TONE GENERATOR.-- The tone generator is a

switch is in the VISUAL position.

type IC/E3D2 electronic signal unit. The tone generator

receives inputs from the alarm relays located in the

DIMMER CONTROL.-- The dimmer control

common board and, in turn, generates the appropriate

dims the alarm module display lamps in all conditions

audible signal over the speaker. A wailing tone is gen-

except flashing.

erated for an alarm condition. A steady tone is generated

SPEAKER.-- The speaker sounds an audible

for a supervisory failure (trouble condition), and a pul-

alarm when the visual-audible switch is set in the

sating tone is generated when there is a loss of power.

AUDIBLE position.

BATTERY.-- The battery supplies power to the

FUSE HOLDER.-- The fuse holder contains the

tone generator to generate the pulsating tone when

two main power fuses for the switchboard. If either fuse

primary power fails. The battery must be hooked

blows, the fuse holder will illuminate to indicate that

up for the switchboard to operate under normal

there is a blown fuse.

9-18