Brushless DC-Servomotors Series 2250 ... BX4

4 Pole Technology

Key Features

Nominal voltage:

12 ... 24 V

Rated torque up to:

26.2 mNm

No-load speed up to:

6400 min⁻¹

Stall torque up to:

152 mNm

Diameter:

22 mm

Length:

51.8 mm

Advantages

High torque and speed rigidity thanks to 4-pole technology

Position control in extremely confined installation spaces thanks to optional analogue Hall sensors

Modular, diameter-compliant mounting concept for high-resolution magnetic and optical encoders

Versions with integrated Speed or Motion Controllers available

High reliability and long service life

Dynamically balanced rotor, quiet running

Variants:

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	12 V
Terminal resistance, phase-phase	R	1.55 Ω
Efficiency, max.	η_max.	76 %
No-load speed	n₀	6000 min⁻¹
No-load current	I₀	0.128 A
Stall torque	M_H	147 mNm
Friction torque, static	C₀	0.8 mNm
Friction torque, dynamic	C_V	2.6 ·10⁻⁴ mNm/min⁻¹
Speed constant	k_n	502 min⁻¹/V
Back-EMF constant	k_E	1.994 mV/min⁻¹
Torque constant	k_M	19 mNm/A
Current constant	k_I	0.053 A/mNm
Slope of n-M curve	Δn/ΔM	40.8 min⁻¹/mNm
Terminal inductance, phase-phase	L	62.8 µH
Mechanical time constant	τ_m	4.3 ms
Rotor inertia	J	10 gcm²
Angular acceleration	α_max.	147 ·10³rad/s²
Thermal resistance	R_th1/R_th2	3.5 / 15 K/W
Thermal time constant	τ_w1/τ_w2	12 / 660 s
Operating temperature range		-40 ... 100 °C
Winding temperature, max.		125 °C
Housing material		stainless steel
Mass		105 g
Direction of rotation		electronically reversible
Speed up to	n_max.	20000 min⁻¹
Number of pole pairs		2
Hall sensors		digital
Magnet material		NdFeB

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	12 V
Terminal resistance, phase-phase	R	1.55 Ω
Efficiency, max.	η_max.	76 %
No-load speed	n₀	6000 min⁻¹
No-load current	I₀	0.128 A
Stall torque	M_H	147 mNm
Friction torque, static	C₀	0.8 mNm
Friction torque, dynamic	C_V	2.6 ·10⁻⁴ mNm/min⁻¹
Speed constant	k_n	502 min⁻¹/V
Back-EMF constant	k_E	1.994 mV/min⁻¹
Torque constant	k_M	19 mNm/A
Current constant	k_I	0.053 A/mNm
Slope of n-M curve	Δn/ΔM	40.8 min⁻¹/mNm
Terminal inductance, phase-phase	L	62.8 µH
Mechanical time constant	τ_m	4.3 ms
Rotor inertia	J	10 gcm²
Angular acceleration	α_max.	147 ·10³rad/s²
Thermal resistance	R_th1/R_th2	3.5 / 15 K/W
Thermal time constant	τ_w1/τ_w2	12 / 660 s
Operating temperature range		-40 ... 100 °C
Winding temperature, max.		125 °C
Housing material		stainless steel
Mass		105 g
Direction of rotation		electronically reversible
Speed up to	n_max.	20000 min⁻¹
Number of pole pairs		2
Hall sensors		digital
Magnet material		NdFeB

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	18 V
Terminal resistance, phase-phase	R	3.17 Ω
Efficiency, max.	η_max.	76 %
No-load speed	n₀	6400 min⁻¹
No-load current	I₀	0.094 A
Stall torque	M_H	152 mNm
Friction torque, static	C₀	0.8 mNm
Friction torque, dynamic	C_V	2.6 ·10⁻⁴ mNm/min⁻¹
Speed constant	k_n	354 min⁻¹/V
Back-EMF constant	k_E	2.825 mV/min⁻¹
Torque constant	k_M	27 mNm/A
Current constant	k_I	0.037 A/mNm
Slope of n-M curve	Δn/ΔM	41.6 min⁻¹/mNm
Terminal inductance, phase-phase	L	126 µH
Mechanical time constant	τ_m	4.3 ms
Rotor inertia	J	10 gcm²
Angular acceleration	α_max.	152 ·10³rad/s²
Thermal resistance	R_th1/R_th2	3.5 / 15 K/W
Thermal time constant	τ_w1/τ_w2	12 / 660 s
Operating temperature range		-40 ... 100 °C
Winding temperature, max.		125 °C
Housing material		stainless steel
Mass		105 g
Direction of rotation		electronically reversible
Speed up to	n_max.	20000 min⁻¹
Number of pole pairs		2
Hall sensors		digital
Magnet material		NdFeB

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	18 V
Terminal resistance, phase-phase	R	3.17 Ω
Efficiency, max.	η_max.	76 %
No-load speed	n₀	6400 min⁻¹
No-load current	I₀	0.094 A
Stall torque	M_H	152 mNm
Friction torque, static	C₀	0.8 mNm
Friction torque, dynamic	C_V	2.6 ·10⁻⁴ mNm/min⁻¹
Speed constant	k_n	354 min⁻¹/V
Back-EMF constant	k_E	2.825 mV/min⁻¹
Torque constant	k_M	27 mNm/A
Current constant	k_I	0.037 A/mNm
Slope of n-M curve	Δn/ΔM	41.6 min⁻¹/mNm
Terminal inductance, phase-phase	L	126 µH
Mechanical time constant	τ_m	4.3 ms
Rotor inertia	J	10 gcm²
Angular acceleration	α_max.	152 ·10³rad/s²
Thermal resistance	R_th1/R_th2	3.5 / 15 K/W
Thermal time constant	τ_w1/τ_w2	12 / 660 s
Operating temperature range		-40 ... 100 °C
Winding temperature, max.		125 °C
Housing material		stainless steel
Mass		105 g
Direction of rotation		electronically reversible
Speed up to	n_max.	20000 min⁻¹
Number of pole pairs		2
Hall sensors		digital
Magnet material		NdFeB

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	24 V
Terminal resistance, phase-phase	R	5.9 Ω
Efficiency, max.	η_max.	77 %
No-load speed	n₀	6200 min⁻¹
No-load current	I₀	0.066 A
Stall torque	M_H	151 mNm
Friction torque, static	C₀	0.8 mNm
Friction torque, dynamic	C_V	2.6 ·10⁻⁴ mNm/min⁻¹
Speed constant	k_n	255 min⁻¹/V
Back-EMF constant	k_E	3.927 mV/min⁻¹
Torque constant	k_M	37.5 mNm/A
Current constant	k_I	0.027 A/mNm
Slope of n-M curve	Δn/ΔM	40.3 min⁻¹/mNm
Terminal inductance, phase-phase	L	250 µH
Mechanical time constant	τ_m	4.2 ms
Rotor inertia	J	10 gcm²
Angular acceleration	α_max.	151 ·10³rad/s²
Thermal resistance	R_th1/R_th2	3.5 / 15 K/W
Thermal time constant	τ_w1/τ_w2	12 / 660 s
Operating temperature range		-40 ... 100 °C
Winding temperature, max.		125 °C
Housing material		stainless steel
Mass		105 g
Direction of rotation		electronically reversible
Speed up to	n_max.	20000 min⁻¹
Number of pole pairs		2
Hall sensors		digital
Magnet material		NdFeB

Values at 22° and nominal voltage		Value
Nominal voltage	U_N	24 V
Terminal resistance, phase-phase	R	5.9 Ω
Efficiency, max.	η_max.	77 %
No-load speed	n₀	6200 min⁻¹
No-load current	I₀	0.066 A
Stall torque	M_H	151 mNm
Friction torque, static	C₀	0.8 mNm
Friction torque, dynamic	C_V	2.6 ·10⁻⁴ mNm/min⁻¹
Speed constant	k_n	255 min⁻¹/V
Back-EMF constant	k_E	3.927 mV/min⁻¹
Torque constant	k_M	37.5 mNm/A
Current constant	k_I	0.027 A/mNm
Slope of n-M curve	Δn/ΔM	40.3 min⁻¹/mNm
Terminal inductance, phase-phase	L	250 µH
Mechanical time constant	τ_m	4.2 ms
Rotor inertia	J	10 gcm²
Angular acceleration	α_max.	151 ·10³rad/s²
Thermal resistance	R_th1/R_th2	3.5 / 15 K/W
Thermal time constant	τ_w1/τ_w2	12 / 660 s
Operating temperature range		-40 ... 100 °C
Winding temperature, max.		125 °C
Housing material		stainless steel
Mass		105 g
Direction of rotation		electronically reversible
Speed up to	n_max.	20000 min⁻¹
Number of pole pairs		2
Hall sensors		digital
Magnet material		NdFeB

Operating Area

Recommended operation areas at nominal voltage 12 V

The diagram indicates the recommended speed in relation to the available torque at the output shaft for a given ambient temperature of 22°C.

The diagram shows the motor in a completely insulated as well as thermally coupled condition (R_th2 50% reduced).

The nominal voltage (U_N) curve shows the operating point at nominal voltage in the insulated and thermally coupled condition. Any points of operation above the curve at nominal voltage will require a higher operating voltage. Any points below the nominal voltage curve will require less voltage.

Characteristic curves of motor