60
Step 13 —
Adjust Factory-Installed Options
SMOKE DETECTORS
Smoke detector(s) will be connected at the Integrated Staging
Control (ISC) board, at terminals marked “Smoke Shutdown”.
Remove jumper JMP 3 when ready to energize unit.
Step 14 —
Install Accessories
Available accessories include:
• Roof Curb (must be installed before unit)
• Thru-base connection kit (must be installed before unit is
set on curb)
• EconoMi$er
®
X (with control)
• Power Exhaust
• Outdoor enthalpy sensor
• Differential enthalpy sensor
• CO
2
sensor
• Temperature and Humidity sensors
• Louvered hail guard
• Phase monitor control
Refer to separate installation instructions for information on in
-
stalling these accessories. See Price Pages for a complete list of
field-installed accessories.
Step 15 —
Check Belt Tension
Measure the belt span length as shown in Fig. 76. Calculate the re
-
quired deflection by multiplying the belt span length by
1
/
64
. For
example, if the belt span length is 32 inches:
32 x
1
/
64
=
1
/
2
-in. deflection.
BELT FORCE — DEFLECTION METHOD
Check the belt tension with a spring-force belt force deflection
gage (available from drive belt manufacturer).
1. Place a straightedge along the belt between the two pul
-
leys. Measure the distance between the motor shaft and the
blower shaft.
2. Set the tension gage to the desired tension (see Table 1 in
Fig. 76). Place the large O-ring at that point.
3. Press the tension checker downward on the belt until the
large O-ring is at the bottom of the straightedge.
4. Adjust the belt tension as needed.
Adjust belt tension by loosing the motor mounting plate front bolts
and rear bolt (see Fig. 77) and slide the plate towards the fan (to
reduce tension) or away from the fan (to increase tension). Ensure
the blower shaft and motor shaft are parallel to each other (pulleys
aligned). Tighten all bolts securely when finished.
Fig. 76 —
V-Belt Force Label
BELT TENSION METHOD
Requires belt tension gage that measures tension in belt in units of
lbs force.
Fig. 77 —
Belt Drive Motor Mounting
TORQUE ALL SHEAVE SET SCREWS TO 110-130 in. lbs
SET
SCREW
SET
SCREW
STRAIGHT
EDGE
BELT SPAN
BELT DEFLECTION FORCE - SEE TABLE 1
DEFLECTION = BELT SPAN
64
Table 1
Table 2
BELT
CROSS
SECTION
SMALLEST
SHEAVE
DIAMETER
BELT DEFLECTION FORCE (LBS)
UNNOTCHED
BELTS
NOTCHED BELTS
USED
NEW
USED
NEW
A, AX
3.0-3.6
3.7
5.5
4.1
6.1
3.8-4.8
4.5
6.8
5.0
7.4
5.0-7.0
5.4
8.0
5.7
8.4
B, BX
3.4-4.2
—
—
4.9
7.2
4.4-5.6
5.3
7.9
7.1
10.5
5.8-8.6
6.3
9.4
8.5
12.6
BELT CONDITION
TENSION FORCE IN BELT (LBS)
New
100
Used
80
BLOWER PULLEY
V-BELT
MOTOR
PULLEY
MOTOR
MOTOR MOUNTING
PLATE
MOUNTING
BOLTS (4)
Summary of Contents for 48LC Series
Page 5: ...5 Fig 2 Unit Dimensional Drawing Size 08 Unit ...
Page 6: ...6 Fig 2 Unit Dimensional Drawing Size 08 Unit cont ...
Page 7: ...7 Fig 3 Unit Dimensional Drawing Size 09 and 12 Units ...
Page 8: ...8 Fig 3 Unit Dimensional Drawing Size 09 and 12 Units cont ...
Page 11: ...11 Fig 6 Roof Curb Details Size 08 12 Units ...
Page 21: ...21 Fig 34 48LC 08 12 Electro mechanical Control Wiring Diagram ...
Page 22: ...22 Fig 35 48LC 08 12 RTU Open Control Wiring Diagram ...
Page 23: ...23 Fig 36 48LC 08 12 SystemVu Control Wiring Diagram ...
Page 25: ...25 Fig 38 48LC 08 12 Typical Power Wiring Diagram SystemVu Control 208 230 v Unit Shown ...
Page 61: ......