Federal Signal Corporation 2001SRNB, Installation And Operating Instructions Manual

Page: 16 / 19

9
4-3. CORRECTIVE MAINTENANCE.
This section includes illustrations that
may be helpful if the siren or rotator needs
repair.
WARNING
To prevent siren from sounding or
rotating, always turn off power at the
disconnect switch and disconnect
the 48VDC, 4AWG red wire in the
Control Unit before performing any
maintenance on the siren.
A. Drive Band Adjustment.
1. When the drive band requires
adjustment, tightening is almost always
necessary. To determine if a drive band
adjustment is required:
(a). Turn off power to the siren at
the disconnect switch. Remove the 48VDC,
4AWG red wire in the Control Unit.
(b). Attach a spring scale having a
capacity of at least 50 pounds (22kg.) to the
horn of the siren as shown in figure 4-1.
0 20
12
0
10
0
80 60 40
291301A
Figure 4-1. Spring Scale Attachment to Siren.
(c). Pull on the scale until the horn
begins to rotate. Continue to rotate the horn
by pulling on the scale while reading the
scale. The scale should indicate between 25
to 30 pounds (11 and 13kg.). It may require
more than 40 pounds of force to start the
horn moving. However, after the horn is
moving, the scale indication should decrease
to some force within the specified range. If
the scale does not indicate between 25 and
30 pounds (11 and 13kg.), the drive band
requires adjustment.
2. To adjust the drive band:
(a). Perform steps (a)., (b)., and (c).
in paragraph 4-3.A.1. (above) to determine if
a drive band adjustment is necessary.
(b). Ensure that power to the siren
is disconnected.
(c). Remove the panel opposite the
conduit fitting on the rotator housing.
(d). Tighten the cross bolt with the
spring one or two turns (see figure 4-2). DO
NOT tighten or loosen the cross bolt without
the spring. Attach the scale to the horn and
pull on the scale to rotate the horn. If the
scale does not indicate between 25 and 30
pounds (11 and 13kg.), repeat this step until
the scale indicates the proper force.
291300A
PINION GEAR SPUR GEAR
ROTATOR
GEARMOTOR
TERMINAL
BLOCK
SIDE
PANELS
291300A
PINION GEAR SPUR GEAR
ROTATOR
GEARMOTOR
TERMINAL
BLOCK
SIDE
PANELS
SPRING
Figure 4-2. Rotator Assembly Interior
CAUTION
If the cross bolt with the spring is
tightened so that more than 40
pounds (18kg.) of pull is necessary
to maintain manual horn rotation,
high winds may cause damage to
the rotator drive mechanism.
(e).
Replace the panel on the
rotator housing.