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SSCBL-RPBL-IOM (10-22) 149159-C
Figure 44. Split Taper Bushing
Reversing Blower Rotation
Each blower housing is marked for proper rotation . Rotation may be changed on single-phase motors by rewiring in
the motor terminal box . Rotation may be changed on three-phase motors by interchanging two wires on the three-
phase supply connections .
Motor Load and Amp Adjustment
•
Amps may be adjusted downward by reducing blower RPM or by increasing duct system static pressure . Use an
ammeter to check blower motor amps .
•
See the motor rating plate for exact motor specifications . Do not exceed the amp rating on the motor nameplate .
•
Venter motor amps for a 115V or 575V unit = 1 .5A . Venter motor amps for a 208V, 230V, or 460V unit = 0 .8A .
•
, which lists the Full Load Amps (FLA) of blower motors (open) based on Horsepower (HP) and Voltage
(V), can be used for sizing line wiring but should not be interpreted as the exact motor amps .
CAPSCREW
PUSH-OFF HOLE
Table 30. FLA of Blower Motors (Open, Single-Speed, Average Values)
Voltage/Phase
HP
1
1-1/2
2
3
5
7-1/2
10
15
20
FLA
208V/1PH
7 .2
10 .1
11 .3
13 .7
28 .0
—
230V/1PH
6 .5
9 .1
10 .2
12 .4
26 .0
32 .0
38 .0
—
208V/3PH
3 .6
5 .8
7 .3
9 .3
14 .6
23 .2
28 .8
42 .0
55 .3
230V/3PH
3 .2
5 .2
6 .6
8 .4
13 .2
21 .0
26 .0
38 .0
50 .0
460V/3PH
1 .6
2 .6
3 .3
4 .2
6 .6
10 .5
13 .0
19 .0
25 .0
575V/3PH
1 .3
2 .1
2 .6
3 .4
5 .3
8 .4
10 .4
15 .2
20 .0
•
At final adjustment, amperes should not exceed motor nameplate amp rating . The installation must be adjusted
to obtain a temperature rise within the range specified on the furnace rating plate .
NOTE: Some blower pulleys require the use of a split taper bushing in the blower pulley. These
split taper bushings must be loosened in order to remove the pulley.
•
If it is necessay to remove a blower pulley, follow these instructions to loosen the bushing:
) . Remove three capscrews .
b . Insert two capscrews into two push-off holes and tighten evenly until pulley is loosened .
c . Pulley may now be removed from shaft .
