NEMA Gearhead: Sample Gearhead Inertia

NEMA 17 Planetary Gear Head
Ratio	Stage	Efficiency %	Inertia Reflected Back to Motor Pinion (oz-in-sec^2)
3:1	Single	90	0.000171
4:1	Single	90	0.000123
5.5:1	Single	90	0.0000767
7:1	Single	90	0.0000513
10:1	Single	90	0.0000272
16:1	Double	85	0.000117
22:1	Double	85	0.000113
28:1	Double	85	0.000111
40:1	Double	85	0.0000245
49:1	Double	85	0.0000448
55:1	Double	85	0.0000238
70:1	Double	85	0.0000235
100:1	Double	85	0.0000233

NEMA 23 Planetary Gear Head
Ratio	Stage	Efficiency %	Inertia Reflected Back to Motor Pinion (oz-in-sec^2)
3:1	Single	90	0.00053
4:1	Single	90	0.00035
5.5:1	Single	90	0.000212
7:1	Single	90	0.00014
10:1	Single	90	0.0000735
16:1	Double	85	0.0000412
22:1	Double	85	0.000399
28:1	Double	85	0.000394
40:1	Double	85	0.000789
49:1	Double	85	0.000148
55:1	Double	85	0.000077
70:1	Double	85	0.0000762
100:1	Double	85	0.0000755

NEMA 34 Planetary Gear Head
Ratio	Stage	Efficiency %	Inertia Reflected Back to Motor Pinion (oz-in-sec^2)
3:1	Single	90	0.00432
4:1	Single	90	0.00267
5.5:1	Single	90	0.00149
7:1	Single	90	0.000951
10:1	Single	90	0.00048
16:1	Double	85	0.00227
22:1	Double	85	0.00217
28:1	Double	85	0.00213
40:1	Double	85	0.000404
49:1	Double	85	0.000755
55:1	Double	85	0.000387
70:1	Double	85	0.000381
100:1	Double	85	0.000376

NEMA 42 Planetary Gear Head
Ratio	Stage	Efficiency %	Inertia Reflected Back to Motor Pinion (oz-in-sec^2)
3:1	Single	90	0.0142
4:1	Single	90	0.00846
5.5:1	Single	90	0.0046
7:1	Single	90	0.00287
10:1	Single	90	0.00142
16:1	Double	85	0.00855
22:1	Double	85	0.00823
28:1	Double	85	0.00811
40:1	Double	85	0.00143
49:1	Double	85	0.00274
55:1	Double	85	0.00137
70:1	Double	85	0.00136
100:1	Double	85	0.00134