The BLH-S1 is a low power brushless linear servo amplifier in a 3E Edge Mount format. It is ideally suited to high precision positioning applications or if electrical noise and excess motor heating cannot be tolerated, or when low inertia/low inductance loads must be driven. This amplifier can be configured for External Sinusoidal commutation or for self commutation using Digital Hall effect sensors. Look to the BLH-S3 if analog hall sensors are required. 

The BLH-S1 is a single card unit with a small plug in Personality Component Carrier to allow customized component changes for the peak current, gain, and integration factors. Hall effect commutation or external sinusoidal commutation is jumper selectable. When using external sinusoidal commutation, the amplifier recieves two  120 out of phase sinusoidal command inputs. The optimal third phase is derived by the amplifier. This eliminates "cogging" and greatly enhances low speed operation. An optional backplane is available to allow quick and easy access to motor, power, control and other I/O signals.


  • 3E Edge Mount Format
  • Accepts Digital Hall Effect Sensors
  • Two Commutation Modes: Hall Effect and External Sinusoidal Input
  • Zero Electrical Noise
  • Travel Limits and Amp Enable Inputs
  • Personality Component Carrier allows Custom Current Loop and Peak Current Configurations
  • Bus Voltage: 20 - 40 VDC
  • Continuous Current: 2 or 4 Amperes
  • Excellent for use with Precision Positioning Systems
  • Hall Power generated from Bus Voltage
  • Designed for Three-Phase Wye or Delta Wound Motors
  • Advanced Design, Superior Quality and High Reliability
  • One Year Parts and Labor Warranty


Standard Models: 4/8 4/15
Bus Voltage 20 to 40  VDC 20 to 40 VDC
Peak Output Current* 8 A for .5 Sec 15 A for .5 Sec
Continuous Output Current* 2 A RMS 4 A RMS
Command Input Voltage:

     Hall Commutation

     Sinusoidal Commutation


0 to 10V

0 to 5V


0 to 10V

0 to 5V

Command Input Impedance 40 kOhm 40 kOhm
Minimum Load Inductance 0 H 0 H
Torque Gain:

     Hall Mode

     Sinusoidal Mode


0.8 A/V

1.6 A/V


1.5 A/V

3.0 A/V

Bandwidth 20 KHz 20 KHz
Weight 0.45 Lb (204 g)
Recommended Chassis EPS, LDP

*All ratings with forced air cooling to maintain 40C heat sink temperature. Failure to keep constant air flow to the heat sink will reduce the output current capacity and may result in damage to the unit.

Ordering Information

Product Order Number
BLH-S1-4/8 Amplifier 40 VDC/8A Peak WS-001-0001
BLH-S1-4/15 Amplifier 40 VDC/15A Peak WS-001-0002

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