Document B8wVO7drjk7raGyer9VprOYpo
HEATINC VENTILATING AIR CONDITIONING GUIDE 1942
CURRENT
Table 1. Classification of Motors
Speed Ohara rv
Txanmcs
Full Voltage
Starting Torque
Starting Current
Hp
Range.
Ttpb op Application Sbe Footnote*
1. Shunt
Direct
2. Compound
3. Series
Constant Speed Drives Constant Medium Medium All
Constant High or Variable
Variable High
Medium All Medium Small
(a) Fans and (c) Centrifugal Pumps
V>) (e) (e) Recipro cating Pumps and fre quent or handstarting
(d) Fans direct connected
Poly
phase
4. Squirrel Cage Constant Normal High , All
General Purpose
6-8 Times
(o) Fans and
(e) Centrifugal Pumps
5. Squirrel Cage Constant Normal Medium Medium (a) Fans and
Medium Torque
5-6 Times Small. Centrifugal Pumps
6. Squirrel Cage High Torque
Constant High
Medium Medium (4) Reciprocating 5-6 Times Small Pumps
() and Compressors started loaded
7. Automatic Start Constant High High Torque
Low 3 Times
Medium
(6) Reciprocating Pumps
(e) and Compressors started loaded
8. Slip Ring
Constant High
Wound Rotor
Low
All
1 -3 Times
with sec
ondary
control
(a) and Hoists (4) Reciprocating Pumps (c) and Frequent (e) or Hand.Start
9. Synchronous ' High Speed
Constant Medium Medium Medium (n) Fans and Cen 5-7 Times Large trifugal Pumps
10, Synchronous Low Speed
Constant Low .
Low Medium (a) Reciprocating 3r4 Times Large Compressors start
ing unloaded
Single
phase
11. Capacitor
Constant High
Normal Medium (6) Pumps and Small Compressors
*Applications: ' , a. Drives having medium or low starting torque and inertia (FF*) such as fans and centrifugal pumps or reciprocating pumps and compressors started unloaded'. . . b. Drives having high starting torques, such as reciprocating pumps and compressors started loaded.
c. Similar to (a) except where frequent or hand starting (large WR?) requires a higher starting and accelerating torque.
d. Fans direct connected. . Stoker drives.
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CHARTER 36. MOTORS AND MOTOR CONTROLS
--
Cgbbsnt
Table X. Classification of Motors--(Continued)
Ttpb
Chaea<>
TERIETtCS
Full Voltage
Starting Torque
Starting Current
Hp Range
Ttpb op Application
See Footnote*
Single
phase
12. Capacitor Fan Constant High
Medium Medium (a) Fans--belted Small
13. Capacitor Fan Constant Low
Medium Medium (d) Fans--direct Small
14. Capacitor Start Constant Any Induction Run
Medium Medium (a) Fans Small (b) Pumps and Compressors
15. Repulsion Induction
Constant High
Medium Medium () Fans Small () Pumps and Compressors
16. Repulsion Start Constant High Induction Run
Medium Medium (a) Fans Small (5) Pumps and Compressors
17. Split Phase
Constant Medium Medium Frac and tional Adjust able
(a) Fans (4) Pumps and
Compressors
Adjustable Speed Drives
18. Shunt' Field Adjustment"
Constant Medium Medium All
Direct 19. Shunt Armature Variable Medium Medium All . Resistor
(a) Fans and (e) Centrifugal Pumps
(a) Fans arid " ' (e) Centrifugal Pumps
! . . .
Poly
phase
20! Squirrel Cage " Variable Medium Medium Medium (a) Fans'
High Slip,' ;
Small
. Tapped Winding
21. Squirrel'Cage , Variable High Slip, Trans-
; former Adjust-
ment
Medium
Medium
Medium Small
(a) Fans
22. Squirrel Cage Constant Medium Separate Wind- Multi- or High
' ing or Regrouped Speed
Poles
Low
All
(a) Fans (4) Pumps and
(c) Compressors i
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