4 – 8
Section 4 • Operation
VSS/VSR/VSM/VSH/VSSH Compressor • Installation, Operation and Service Manual • Emerson • 35391S
Compressor
Model
Command Shaft Rotation
No. of Turns/Rotation
Angle/Slide Travel
Capacity
Volume
Capacity
Volume
INC
DEC
INC
DEC
Turns
Degrees
Travel
Turns
Degrees
Travel
VSM 71
VSM 91
VSM 101
VSM 151
VSM 181
VSM 201
VSM 301
VSM 361
VSM 401
CW
CCW
CW
CCW
0.80
288
3.141”
0.45
162
1.767”
VSM 501
VSM 601
VSM 701
CCW
CW
CCW
CW
0.91
328
3.568”
0.52
187
2.045”
VSS/VSSH 291
VSS/VSSH 341
VSS/VSSH 451
VSS/VSSH 601
CW
CCW
CW
CCW
0.91
328
3.568”
0.52
187
2.045”
VSS 751
VSS 901
CCW
CW
CCW
CW
1.09
392
4.283”
0.63
227
2.473”
VSS/VSH 791
VSS/VSH 891
VSS/VSH 1051
VSS/VSH 1201
VSS/VSH 1301
CCW
CW
CCW
CW
1.22
439
4.777”
0.74
266
2.889”
VSS 1501
CCW
CW
CCW
CW
1.36
490
5.325”
0.82
295
3.200”
VSS 1551
CCW
CW
CCW
CW
1.48
533
5.823”
0.87
313
3.433”
VSS 1801
CCW
CW
CCW
CW
1.36
490
5.325”
0.82
295
3.200”
VSS 1851
VSS 2101
CCW
CW
CCW
CW
1.48
533
5.823”
0.87
313
3.433”
VSS 2401
VSS 2601
VSS 2801
VSS 3001
CCW
CW
CCW
CW
1.80
648
7.072”
1.36
490
5.341”
Table 4-1. Command Shaft Rotation Specifications*
*The large gear on the command shaft has 50 teeth. The teeth are counted when moving the command shaft from the
minimum stop position to the maximum stop position.
The manual operating shaft on the gear motor should be turned the opposite direction of the desired command shaft
rotation.
The capacity and volume control motors are equipped with a brake, if it is necessary to operate the control motors manu-
ally, the brake must be disengaged. The brake can be disengaged by pushing on the motor shaft on the cone end. The shaft
should be centered in its travel. Do not use excessive force manually operating the motor or damage may result.