Motor Technology - BHL series
spares parts request brushless servo drives up to 8kW
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The compact design of the BHL drives suite a wide range of motors and are available in 5 sizes, up to 8 KW for motors with tacho generator and Hall effect position sensors.


Easy installation and set-up connections on the front side and built-in power supply.


Supply voltage 220 Vac 3-phase, fully protected opto isolated IGBT power stage, high frequency PWM modulation gives very high efficiency.




BHL can be used in industrial automation, in mobile robots, in textile machines, in packaging machines and in all special machines where full custom turn-key solutions at high ratio performance/price are requested.




Power supply
Three phase 220 Vac (+10%, -15%) with internal supply derived from DC bus.
Optional 110/220 Vac auxiliary input for the internal power supply.

Output ratings
310 Vdc nominal bus voltage (98% max output voltage)
Continous output current : 5/8/12/20/27 A
Peak output current: 12/20/30/50/55 A
(Peak output current can last 10s with the motor rotating, or 0,7s at stall)

Ballast resistor
Ballast short circuit protected
Internal resistor for Pd < 50W (option)
External resistor connection

Braking system
Dynamic braking function with pre-settable current Direct control of electromagnetic brake
Internal supply for 24 Vdc brake (0.8 A max)
Provision for external safety series contact

Tachogenerator interface
Interface for three-phase brushless
tacho-generator with 4 sensitive ranges, up to 15 Vdc power supply
Selectable coding 60° / 120 °

Input/output signals
Power Enable digital input (optocoupled)
Reference Enable digital input (optocoupled)
Reference analog input ±10V(differential)
Current limit analog input 0-10 V (option)
Drive OK output (relay contact)
±15V 50mA power supply output

Functional characteristics
Speed control or current control, user selectable
Ramp generation function (option)

Protection functions
Short circuit of motor output terminals
Drive overcurrent
Drive overtemperature
Hall sensor and tachogenerator connection error
Motor overtemperature
Ixt circuit
Protection intervention is signalled by a red LED on front panel. On protection intervention the ‘Drive OK’ contact is opened.

Parameters personalization via plug-in board on front panel :
Max motor current
Continous motor current
Tachogenerator input range and gain
P.I. regulator of current loop
P.I. regulator of speed loop
Dynamic braking current
Protection intervention thresholds

BHL series servo amplifiers take in different sensor interfaces
commonly mounted on brushless motors.

At present two version are available :

· Programmable Resolver interface 12-14-16 bit resolution
· Encoder simulation output A,B,Z (RS422 differential)
with programmable resolution from 128 to 16384 pulse/revolution
· Customization of motor poles number (2,4,6,8,12)
· Resolver connection error
· Resolver 12 KHZ excitation (settable amplitude 3,5 ÷ 7 Vrms)
· Input voltage SIN,COS signals 2 Vrms
· Trimmer compensation of REF to SIN, COS phasing error

· Three-phase brushless tacho-generator interface
with 4 sensitivity ranges up to 50 Vmax
· DC brushed tacho-generator interface
· Position sensor (HALL sensor) with 15 Vdc supply
· Selectable coding 60° / 120°
· HALL sensor and tacho-generator connection error