BLMH Series Linear Motors
The BLMH series “U-channel” brushless linear servomotors offer over 70% greater continuous output force (in the same physical envelope) than other manufacturers’ similar models. BLMH series motors feature a high-efficiency magnetic circuit design that provides continuous force ratings to 548.8 N (123.4 lb) and peak forces to 2195 N (493.5 lb). Enhance this extremely high level of performance with special magnet options that increase force and lower heat generation.
- Description
- Specifications
- Dimensions
- Ordering Info
- Downloads
Design Features
- 70% greater continuous output force in the same physical envelope than competitive models
- Continuous forces up to 548.8 N (123.4 lb); peak forces to 2195 N (493.5 lb)
- Special magnet options available for increased force output
- 114.1 mm high x 50.8 mm wide cross section
- CE approved, follows the EU 2015/863 RoHS 3 directive
BLMH series linear motors are direct drive and consist of a noncontact forcer assembly with Hall-effect devices, a thermal sensor, and “U-channel” magnet track. This design eliminates magnetic attraction to allow for extremely smooth motion and very tight velocity and position control. In addition, backlash, windup, wear and maintenance issues associated with ball screws, belts, and rack and pinions are eliminated.
The BLMH series nonmagnetic forcer eliminates cogging and magnetic attraction to allow for extremely smooth motion and very tight velocity and position control. These linear motors are ideal for any application that requires high speeds with high loads. BLMH series linear motors are forgiving to align, easy to assemble, and keep the magnetic field well-contained. Magnet tracks are stackable for any travel length. They are also suited for industrial usage.
The BLMH can be driven using standard Aerotech brushless amplifiers and controllers to provide a complete, integrated system.
BLMH Performance Specifications
| BLMH-142-A | BLMH-142-B | BLMH-262-A | BLMH-262-B | BLMH-382-A | BLMH-382-B | |
|---|---|---|---|---|---|---|
| Continuous Force, 1.4 bar, 20 psi(1)(2)(5) | 270.7 N | 437.1 N | 435.8 N | 548.8 N | ||
| Continuous Force, No Forced Cooling(1)(2)(4) | 150.0 N | 266.2 N | 357.9 N | |||
| Peak Force(1)(3)(4) | 1082.7 N | 1748.6 N | 2195.0 N | |||
- Performance is dependent upon heat sink configuration, system cooling conditions, and ambient temperature.
- Values shown @ 100°C rise above a 25°C ambient temperature, with the motor mounted to the specified aluminum heat sink.
- Peak force assumes correct rms current; consult Aerotech.
- All performance and electrical specifications ±10%.
BLMH Electrical Specifications
| BLMH-142-A | BLMH-142-B | BLMH-262-A | BLMH-262-B | BLMH-382-A | BLMH-382-B | |
|---|---|---|---|---|---|---|
| BEMF Constant (Line-Line, Max)(5) | 32.11 V/(m/s) | 64.22 V/(m/s) | 64.42 V/(m/s) | 128.85 V/(m/s) | 45.71 V/(m/s) | 91.42 V/(m/s) |
| Continuous Current, 1.4 bar, 20 psi (Apk )(1)(5) | 9.69 Apk | 4.85 Apk | 7.80 Apk | 3.90 Apk | 10.96 Apk | 6.90 Apk |
| Continuous Current, 1.4 bar, 20 psi (Arms )(1)(5) | 6.85 Arms | 3.43 Arms | 5.52 Arms | 2.76 Arms | 7.75 Arms | 4.88 Arms |
| Continuous Current, No Forced Cooling (Apk )(1)(5) | 5.37 Apk | 2.69 Apk | 4.75 Apk | 2.38 Apk | 9.00 Apk | 4.50 Apk |
| Continuous Current, No Forced Cooling (Arms )(1)(5) | 3.80 Arms | 1.90 Arms | 3.36 Arms | 1.68 Arms | 6.36 Arms | 3.18 Arms |
| Peak Current, Stall (Apk )(2)(5) | 38.76 Apk | 19.38 Apk | 31.20 Apk | 15.60 Apk | 55.20 Apk | 27.60 Apk |
| Peak Current, Stall (Arms )(2)(5) | 27.41 Arms | 13.70 Arms | 22.06 Arms | 11.03 Arms | 39.03 Arms | 19.52 Arms |
| Force Constant, Sine Drive-N/Apk (3)(4)(5) | 27.93 N/Apk | 55.87 N/Apk | 56.04 N/Apk | 112.09 N/Apk | 39.77 N/Apk | 79.53 N/Apk |
| Force Constant, Sine Drive-N/Arms (3)(4)(5) | 39.50 N/Arms | 79.01 N/Arms | 79.26 N/Arms | 158.52 N/Arms | 56.24 N/Arms | 112.47 N/Arms |
| Motor Constant(1)(3)(5) | 14.17 N/√W | 20.24 N/√W | 23.19 N/√W | |||
| Resistance, 25°C (Line-Line)(4) | 3.7 Ω | 14.8 Ω | 7.3 Ω | 29.2 Ω | 2.8 Ω | 11.2 Ω |
| Inductance (Line-Line)(4) | 2.40 mH | 9.60 mH | 4.60 mH | 18.40mH | 1.80 mH | 7.20 mH |
| Thermal Resistance, 1.4 bar, 20 psi(4) | 0.27 °C/W | 0.21 °C/W | 0.18 °C/W | |||
| Thermal Resistance, No Forced Cooling(4) | 0.89 °C/W | 0.58 °C/W | 0.42 °C/W | |||
| Maximum Bus Voltage(4) | 340 VDC | |||||
BLMH Specifications
| BLMH-142-A | BLMH-142-B | BLMH-262-A | BLMH-262-B | BLMH-382-A | BLMH-382-B | |
|---|---|---|---|---|---|---|
| Air Flow (20 psi) | 2.5x10-3 m 3/s /m5.3 SCFM | 2.8x10-3 m 3/s 5.9 SCFM | 2.7x10-3 m 3/s 5.8 SCFM | |||
| Coil Weight | 1.10 kg | 2.10 kg | 3.10 kg | |||
| Coil Length | 142.0 mm | 262.0 mm | 382.0 mm | |||
| Heat Sink | 250x250x25 mm | 250x400x25 mm | ||||
| Magnet Track Weight | 20.4 kg/m | |||||
| Magnetic Pole Pitch | 30.00 mm | |||||
| Standards | EU 2015/863 RoHS 3 directive | |||||

BLMH Brushless Linear Servomotor
| Option | Description |
|---|---|
| BLMH-142 | Linear motor forcer with thermistor; 142 mm long |
| BLMH-262 | Linear motor forcer with thermistor; 262 mm long |
| BLMH-382 | Linear motor forcer with thermistor; 382 mm long |
Winding Designation (Required)
| Option | Description |
|---|---|
| -A | 76 cm (2.5 ft) flying leads (standard) |
- Contact factory to inquire about or check availability of alternate winding options.
Air Cooling (Required)
| Option | Description |
|---|---|
| -NC | No air cooling fitting is installed |
| -AC | Included air cooling fitting |
Hall Effect Sensors (Required)
| Option | Description |
|---|---|
| -H | Hall effect sensors included |
| -NH | No Hall effect sensors included |
Preparations (Required)
| Option | Description |
|---|---|
| -S | Standard |
| -V | Vacuum preparation for 10-6 Torr |
| -UHV | Ultra-high vacuum preparation; contact factory |
Magnet Tracks (Optional)
| Option | Description |
|---|---|
| MTH180P | "U" channel magnet track for use with BLMH-series forcers; 180 mm long |
| MTH210P | "U" channel magnet track for use with BLMH-series forcers; 210 mm long |
| MTH240P | "U" channel magnet track for use with BLMH-series forcers; 240 mm long |
| MTH300P | "U" channel magnet track for use with BLMH-series forcers; 300 mm long |
| MTH330P | "U" channel magnet track for use with BLMH-series forcers; 330 mm long |
| MTH360P | "U" channel magnet track for use with BLMH-series forcers; 360 mm long |
| MTH480P | "U" channel magnet track for use with BLMH-series forcers; 480 mm long |
| MTH600P | "U" channel magnet track for use with BLMH-series forcers; 600 mm long |
| MTH720P | "U" channel magnet track for use with BLMH-series forcers; 720 mm long |
| MTHxP | “U” channel magnet track for use with BLMH-series forcers; custom length |
- Magnet tracks are ordered as separate line items. Magnet track part numbers ending in "P" are high performance grade, including magnets on both sides of the track.
Integrated (Required)
| Option | Description |
|---|---|
| -TAS | Integration - Test as system Testing, integration, and documentation of a group of components as a complete system that will be used together (ex: drive, controller, and stage). This includes parameter file generation, system tuning, and documentation of the system configuration. |
| -TAC | Integration - Test as components Testing and integration of individual items as discrete components that ship together. This is typically used for spare parts, replacement parts, or items that will not be used together. These components may or may not be part of a larger system. |










