Design Features

Standard NEMA frame sizes
Rare-earth magnets maximize performance
Skewed stator design minimizes torque ripple and cogging for smooth velocity control over a wide speed range
Optional IP65-level construction allows use in harsh environments
Optional brake, front shaft seal, and precision gear reducers
Follows the 2011/65/EU RoHS 2 Directive

High-Performance Design

The BM series consists of Aerotech's high-performance brushless permanent magnet rotary servomotors. The motors feature rare-earth magnets for maximum torque and acceleration in a small package. A skewed stator design provides low torque ripple and smooth velocity. Unlike DC brush-type servomotors, the BM series are brushless and maintenance free. This makes them ideal for critical applications where downtime cannot be tolerated.

In addition, the BM series motors have very high power density resulting in high torque in a compact package. Optional IP65 sealing make these motors ideal for harsh environments such as machine tool.

Wide Torque Range

The BM motor series covers a wide range of torque and package sizes. Continuous output torque ranges from 0.16 N·m (22.5 oz·in) to 31.6 N·m (280 lb·in), with peak torques to 94.9 N·m (840 lb·in). Standard frame sizes include NEMA 17, 23, 34, 42 and 56. This makes it easy to mount any motor to Aerotech’s gearbox line with no adapter plates. These motors are well-suited to general purpose and high-end servo applications.

Application Flexibility

The standard motor has a 1000-line encoder (4000-line count after quadrature), RS-422 line driver output with Hall effect device outputs for commutation, and MS connectors. Options include increased encoder resolution, sealing for IP65 level protection, brakes, and gearboxes. Standard models can be delivered from stock and custom variations can be engineered to your requirements with minimal lead time.

Need help sizing your motor? Try Aerotech's Motor Sizer software to specify the ideal motor for your application.

Specifications

BM Series Specifications

Motor Model	Units	BM22	BM75	BM130	BM200
Performance Specifications^(1,2)
Stall Torque, Continuous⁽³⁾	N·m	0.16	0.51	1.02	1.45
Stall Torque, Continuous⁽³⁾	oz·in	22.5	72	144	205
Peak Torque⁽⁴⁾	N·m	0.48	1.3	2.5	3.6
Peak Torque⁽⁴⁾	oz·in	68	181	361	512
Rated Speed	rpm	3000	4000	4000	4000
Rated Power Output, Continuous	W	50	192	333	455
Electrical Specifications⁽²⁾
BEMF Constant (Line-Line, Max)	V_pk/krpm	3.9	9	19	18
Continuous Current, Stall⁽³⁾	A_pk	4.9	9.0	6.9	10.3
Continuous Current, Stall⁽³⁾	A_rms	3.5	6.4	4.9	7.3
Peak Current, Stall⁽⁴⁾	A_pk	14.7	22.5	17.3	25.8
Peak Current, Stall⁽⁴⁾	A_rms	10.4	15.9	12.2	18.2
Torque Constant⁽⁵⁾	N·m/A_pk	0.032	0.06	0.15	0.14
	oz·in/A_pk	4.5	8.0	20.9	19.9
	N·m/A_rms	0.045	0.08	0.21	0.20
	oz·in/A_rms	6.4	11.4	29.6	28.1
Motor Constant^{(3, 5)}	N·m/√W	0.038	0.055	0.101	0.131
Motor Constant^{(3, 5)}	oz·in/√W	5.41	7.84	14.30	18.54
Resistance, 25°C (Line-Line)	Ω	0.67	1.0	2.0	1.1
Inductance (Line-Line)	mH	0.73	1.42	3.52	2.18
Maximum Bus Voltage	VDC	80	340	340	340
Thermal Resistance	°C/W	4.56	1.18	1.04	0.81
Number of Poles	-	8	8	8	8
Mechanical Specifications
Frame Size	NEMA	17	23	23	23
Motor Weight	kg	0.4	1.1	1.5	2.0
Motor Weight	lb	0.88	2.42	3.30	4.40
Rotor Moment of Inertia	kg·m²	2.00x10^-6	5.20x10^-6	9.20x10^-6	1.30x10^-5
Rotor Moment of Inertia	oz·in·s²	0.00028	0.0007	0.0013	0.0018
Max Radial Load	N	78	89	89	89
Max Radial Load	lb	18	20	20	20
Max Axial Load	N	39	89	89	89
Max Axial Load	lb	9	20	20	20
Standards		2011/65/EU RoHS 2 Directive

Performance is dependent upon heat sink configuration, system cooling conditions, and ambient temperature.
All performance and electrical specifications ±10%.
Values shown @ 105°C rise above a 25°C ambient temperature, with motor mounted to a 250 mm x 250 mm x 6 mm aluminum heat sink.
Peak torque assumes correct rms current; consult Aerotech.
Torque constant and motor constant specified at stall.

Motor Model	Units	BM250	BM500
Performance Specifications^(1,2)
Stall Torque, Continuous⁽³⁾	N·m	2.3	3.6
Stall Torque, Continuous⁽³⁾	oz·in	322	515
Peak Torque⁽⁴⁾	N·m	5.7	9.1
Peak Torque⁽⁴⁾	oz·in	805	1286
Rated Speed	rpm	4000	4000
Rated Power Output, Continuous	W	739	1065
Electrical Specifications⁽²⁾
BEMF Constant (Line-Line, Max)	V_pk/krpm	28	29
Continuous Current, Stall⁽³⁾	A_pk	10.3	17.5
Continuous Current, Stall⁽³⁾	A_rms	7.2	12.4
Peak Current, Stall⁽⁴⁾	A_pk	25.6	43.8
Peak Current, Stall⁽⁴⁾	A_rms	18.1	30.9
Torque Constant⁽⁵⁾	N·m/A_pk	0.22	0.21
	oz·in/A_pk	31.4	29.4
	N·m/A_rms	0.31	0.29
	oz·in/A_rms	44.4	41.6
Motor Constant^(3,5)	N·m/√W	0.206	0.287
Motor Constant^(3,5)	oz·in/√W	29.22	40.69
Resistance, 25°C (Line-Line)	Ω	1.1	0.5
Inductance (Line-Line)	mH	2.74	1.42
Maximum Bus Voltage	VDC	340	340
Thermal Resistance	°C/W	0.82	0.74
Number of Poles	-	8	8
Mechanical Specifications
Frame Size	NEMA	34	34
Motor Weight	kg	3.6	5.0
Motor Weight	lb	7.92	11.0
Rotor Moment of Inertia	kg·m²	7.85x10^-5	1.39x10^-4
Rotor Moment of Inertia	oz·in·s²	0.0111	0.0197
Max Radial Load	N	178	178
Max Radial Load	lb	40	40
Max Axial Load	N	89	89
Max Axial Load	lb	20	20
Standards		2011/65/EU RoHS 2 Directive

Performance is dependent upon heat sink configuration, system cooling conditions, and ambient temperature.
All performance and electrical specifications ±10%.
Values shown @ 105°C rise above a 25°C ambient temperature, with motor mounted to a 250 mm x 250 mm x 6 mm aluminum heat sink.
Peak torque assumes correct rms current; consult Aerotech.
Torque constant and motor constant specified at stall.

Motor Model	Units	BM800	BM1400
Electrical Specifications^(1,2)
Stall Torque, Continuous⁽³⁾	N·m	6.1	11.0
	oz·in	866	1562
Peak Torque⁽⁴⁾	N·m	15.3	27.6
	oz·in	2166	3905
Rated Speed	rpm	3000	3000
Rated Power Output, Continuous	W	1446	2529
Electrical Specifications⁽²⁾
BEMF Constant (Line-Line, Max)	V_pk/krpm	69	69
Continuous Current, Stall⁽³⁾	A_pk	11.9	20.5
Continuous Current, Stall⁽³⁾	A_rms	8.4	14.5
Peak Current, Stall⁽⁴⁾	A_pk	29.8	51.3
Peak Current, Stall⁽⁴⁾	A_rms	21.0	36.2
Torque Constant⁽⁵⁾	N·m/A_pk	0.51	0.54
	oz·in/A_pk	72.8	76.2
	N·m/A_rms	0.73	0.76
	oz·in/A_rms	103	107.8
Motor Constant^(3,5)	N·m/√W	0.451	0.745
Motor Constant^(3,5)	oz·in/√W	63.86	105.47
Resistance, 25°C (Line-Line)	Ω	1.2	0.5
Inductance (Line-Line)	mH	3.8	1.7
Maximum Bus Voltage	VDC	340	340
Thermal Resistance	°C/W	0.60	0.54
Number of Poles	-	8	8
Mechanical Specifications
Frame Size	NEMA	42	42
Motor Weight	kg	6.6	10.7
Motor Weight	lb	14.52	23.54
Rotor Moment of Inertia	kg·m²	3.00x10^-4	5.60x10^-4
Rotor Moment of Inertia	oz·in·s²	0.0425	0.0793
Max Radial Load	N	222	222
Max Radial Load	lb	50	50
Max Axial Load	N	89	89
Max Axial Load	lb	20	20
Standards		2011/65/EU RoHS 2 Directive

Performance is dependent upon heat sink configuration, system cooling conditions, and ambient temperature.
All performance and electrical specifications ±10%.
Values shown @ 105°C rise above a 25°C ambient temperature, with motor mounted to a 300 mm x 300 mm x 13 mm aluminum heat sink.
Peak torque assumes correct rms current; consult Aerotech.
Torque constant and motor constant specified at stall.

Motor Model	Units	BM2000	BM3400	BM4500
Performance Specifications^(1,2)
Stall Torque, Continuous⁽³⁾	N·m	14.7	23.7	31.6
Stall Torque, Continuous⁽³⁾	oz·in	2080	3360	4480
Peak Torque⁽⁴⁾	N·m	44.1	71.2	94.9
Peak Torque⁽⁴⁾	oz·in	6240	10080	13440
Rated Speed	rpm	2400	2400	2400
Rated Power Output, Continuous	W	3267	5077	6761
Electrical Specifications⁽²⁾
BEMF Constant (Line-Line, Max)	V_pk/krpm	99.0	99.0	99.0
Continuous Current, Stall⁽³⁾	A_pk	16.5	26.7	35.4
Continuous Current, Stall⁽³⁾	A_rms	11.7	18.9	25.0
Peak Current, Stall⁽⁴⁾	A_pk	49.7	80.3	106.1
Peak Current, Stall⁽⁴⁾	A_rms	35.1	56.7	75.0
Torque Constant⁽⁵⁾	N·m/A_pk	0.89	0.89	0.89
	lb·in/A_pk	7.9	7.9	7.9
	N·m/A_rms	1.25	1.25	1.27
	lb·in/A_rms	11.1	11.1	11.2
Motor Constant^(3,5)	N·m/√W lb-in/√W	1.030 9.10	1.720 15.20	2.320 20.50
Resistance, 25°C (Line-Line)	Ω	0.66	0.24	0.13
Inductance (Line-Line)	mH	4.7	2.0	1.4
Maximum Bus Voltage	VDC	340	340	340
Thermal Resistance	°C/W	0.64	0.68	0.70
Number of Poles	-	6	6	6
Mechanical Specifications
Frame Size	NEMA	56	56	56
Motor Weight	kg	15	23	30
Motor Weight	lb	33.0	49.9	66.9
Rotor Moment of Inertia	kg·m²	1.25x10^-3	2.23x10^-3	3.24x10^-3
Rotor Moment of Inertia	lb·in·s²	0.0111	0.0197	0.0287
Max Radial Load	N	668	668	668
Max Radial Load	lb	150	150	150
Max Axial Load	N	223	223	223
Max Axial Load	lb	50	50	50
Standards		2011/65/EU RoHS 2 Directive

Performance is dependent upon heat sink configuration, system cooling conditions, and ambient temperature.
All performance and electrical specifications ±10%.
Values shown @ 130°C rise above a 25°C ambient temperature, with motor mounted to a 305 mm x 305 mm x 12.7 mm aluminum heat sink.
Peak torque assumes correct rms current; consult Aerotech.
Torque constant and motor constant specified at stall.

Torque Speed Curves 1
Torque Speed Curves 2

Ordering Information

Ordering Options

Series	Connectors	Feedback	Brake	Cable Type	Cable Length	Shaft Seal
BM22 BM75 BM130 BM200 BM250 BM500 BM800 BM1400 BM2000 BM3400 BM4500	-MS -D25 -D25-9D -D25-FLB -D25-5DU -D25-9D-CMS -D25-4TS	-E1000H -E2000H -E2500H -E5000H -E1000ASH	-BK	-HF	-xx	-NS

NEMA Brushless Rotary Servomotors

Option	Description
BM22	NEMA 17 brushless rotary servomotor
BM75	NEMA 23 brushless rotary servomotor
BM130	NEMA 23 brushless rotary servomotor
BM200	NEMA 23 brushless rotary servomotor
BM250	NEMA 34 brushless rotary servomotor
BM500	NEMA 34 brushless rotary servomotor
BM800	NEMA 42 brushless rotary servomotor
BM1400	NEMA 42 brushless rotary servomotor
BM2000	NEMA 56 brushless rotary servomotor
BM3400	NEMA 56 brushless rotary servomotor
BM4500	NEMA 56 brushless rotary servomotor

Connectors (Required)

Option	Description
-MS	Integral cable w/MS connector for Fbk and Mtr (-MS); not available for BM22
-D25	Integral cable w/D25 Fbk and 4D Mtr (-D25); only available on BM22, BM75, BM130, and BM200
-D25-9D	Integral cable w/D25 Fbk, 4D Mtr, and 9D Limit (-D25-9D); only available on BM75, BM130, and BM200
-D25-FLB	Integral cable w/D25 Fbk, Fly Leads for Mtr, and 9D Limit (-D25-FLB); only available on BM75, BM130, and BM200
-D25-5DU	Integral cable w/D25 Fbk, 5D Mtr, and 9D Limit (-D25-5DU); only available on BM75, BM130, and BM200
-D25-9D-CMS	Integral cable w/D25 Fbk, 4D Mtr, and 9D Limit - CMS Only (-D25-9D-CMS); only available on BM75, BM130, and BM200
-D25-4TS	Integral cable w/D25 Fbk, 4TS Mtr, and 9D Limit (-D25-4TS); only available on BM75, BM130, and BM200

Feedback (Required)

Option	Description
-E1000H	1000 lines/rev TTL incremental encoder w/Hall tracks (-E1000H); not available for BM22
-E2000H	2000 lines/rev TTL incremental encoder w/Hall tracks (-E2000H); not available for BM3400 or BM4500
-E2500H	2500 lines/rev TTL incremental encoder w/Hall tracks (-E2500H); not available for BM22
-E5000H	5000 lines/rev TTL incremental encoder w/Hall tracks (-E5000H); not available for BM22
-E1000ASH	1000 lines/rev 1 Vpp incremental encoder w/Hall tracks (-E1000ASH); not available for BM22, BM2000, BM3400 or BM4500

Brake (Optional)

Option	Description
-BK	Holding brake (-BK); not available on BM4500

Cable Type (Optional)

Option	Description
-HF	High flex cable; only available on BM75, BM130, and BM200

Cable Length (dm) (Optional)

Option	Description
-xx	Cable length in decimeters (3.8 dm is default); only available on BM75, BM130, and BM200

Shaft Seal (Optional)

Option	Description
-NS	Nitrile front shaft seal; only available on BM250, BM500, BM800 and BM1400

Vacuum Preparation (Optional)

Option	Description
-VAC6	Vacuum preparation to 10^-6 Torr

Accessories (Optional)

Option	Description
MC-HPD25-M	Connector; HPD motor power mate
MC-DB25-F	Connector; DB25 motor feedback mate
MCM1-3	Connector; MS motor power mate (BM2000, BM3400, BM4500)
MCM-3	Connector; MS motor power mate (BM75, BM130, BM200, BM250, BM500, BM800, BM1400)
MCF-3	Connector; MS motor feedback mate

Note: Accessories are ordered as separate line items.