Glossary for Frameless Motor

Term	Symbol	Unit	Explanation
Continuous torque	MS1	Nm	Continuous torque of the motor.
Continuous power	PS1	W	Continuous power of the motor.
DC bus voltage	UDC	V	Voltage at DC bus.
Torque constant	km	Nm/A	Torque constant calculated from the torque and the RMS current.
Voltage constant	ke	Vs	Voltage constant calculated from the peak value of the induced voltage between two terminals and the rotation speed for the externally driven motor:
Motor constant	kmot	Nm/√W	Factor of efficiency calculated from torque and power losses.
Ambient temperature	ϑu	°C	Maximum allowed ambient temperature (with liquid cooling, maximum inlet temperature of the cooling liquid) without derating.
Maximum winding temperature	ϑmax	°C	Maximum allowed winding temperature.
Thermal resistance	Rth	K/W	Heat transmission resistance must not be exceeded for the dissipation of the thermal losses.
Thermal time constant	t/th	min	Time in which 63% of the final value of the warming at rated loading is reached.
Thermal overload factor	kth	A²s/K	Linearized factor to determine the remaining on-time depending on the current and temperature rise.
Minimal flow rate	Q	l/min	Minimum flow rate of the coolant water.
Maximum power	Pmax	W	Maximum power in short time operation.
Maximum torque	Mmax	Nm	Maximum torque with maximum current Imax.
Maximum current	Imax	A	Maximum current rms value.
Continuous stall torque	M0	Nm	Continuous torque at standstill of the motor.
Continuous stall current	I0 .	A	Continuous current (rms value) which leads to the allowed heating of the winding
No-load speed	n0	min-1	Maximum no-load speed which will be reached without field weakening at operation with UDC.
Rated power	Pn	W	Continuous power at speed nn
Rated torque	Mn	Nm	Continuous torque at speed nn
Rated current	In	A	Continuous current (rms value) at speed nn
Rated speed	nn	min-1	Speed up to which Mn is produced continuously.
Cogging torque	Mcog	Nm	The cogging torque is defined as the maximum peak-to-peak value of two consecutive significant extrema of the cogging torque over one complete revolution
Motor terminal resistance	Rtt	Ω	Resistance between two terminals at 20°C.
Motor terminal inductance	Ltt	mH	Inductance between two terminals at 20°C.
Motor terminal inductance (d-axis)	Lttd	mH	Direct-axis inductance between two terminals at 20°C.
Motor terminal inductance (q-axis)	Lttq	mH	Quadrature-axis inductance between two terminals at 20°C.
Electrical time constant = Ltt / Rtt	te	ms	Electrical time constant, derived from: Te=Ltt/Rtt
Number of pole pairs	p	-	Number of the pole pairs of the motor.
Inertia of motor	J	kgm²	Inertia of the motor without brake.
Inertia active part	J	kgm²	Inertia of the rotor.
Mass of motor	m	kg	Mass of the motor without brake.
Mass active part	m	kg	Mass of the rotor and the stator.

All specified values are liable to specific variabilities due to the tolerances of material properties and dimensions.

The specified values are mean values at which a tolerance of +/-10% of torque, current, inductance, resistance, and speed is allowed.

In addition, the terminal inductance can alternate depending on the angle between the rotor and stator.

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Glossary for Frameless Motor

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Model	OD(mm)	ID(mm)	Height(mm)	Rated Torque(Nm)	Rated Power(W)	Rated Speed(rpm)
U25 Series	25	11.6	10.8~23.4	0.025~0.075	10.48~31.44	4000
U38 Series	38	18	15.3~34.3	0.1~0.35	31.4~110.0	3000
U50 Series	50	28	19.8~37.9	0.27~0.7	84.89~220.08	3000
U60 Series	60	33	17.7~35.8	0.45~0.96	141.48~301.82	3000
U68 Series	68	37	18.3~36.4	0.63~1.54	198.07~484.18	3000
U76 Series	76	42	18.6~36.7	0.89~2.06	279.82~647.66	3000
U85 Series	85	47	19.3~37.4	1.21~2.69	380.42~845.74	3000
U94 Series	94	51	19.7~37.8	1.58~3.67	496.75~576.92	1500~3000
U115 Series	115	65	26.3~44.4	3~6.1	943.2~958.92	1500~3000
U130 Series	130	84	25.9~60.9	5~18	419.2~754.56	400~800
U160 Series	160	106	25.9~60.9	9~32	471.6~670.72	200~500
U200 Series	200	140	25.9~60.9	13~50	408.72~524	100~300

Mode	OD(mm)	ID(mm)	Height(mm)	Rated Torque(Nm)	Rated Power(W)	Rated Speed(rpm)	Voltage(V)
FI-40 Series	40	6.5	48~65	0.25	7.9	300	220
FI-60 Series	60	15	60~80	0.5	15.7	300	220
FE-80 Series	80	15	47~67	1	21	200	220
FI-80 Series	80	12	50	0.9	28.3	300	220
FE-112 Series	112	19	65~95	3	62.9	200	220
FI-120 Series	120	42	64	2.4	37.7	150	220
FE-140 Series	140	30	50~80	6	188.6	300	220
FI-140 Series	140	28	85~188	10.5	220.1	200	220
FE-170 Series	170	42	50~155	4.5	117.9	250	220
FI-170 Series	170	50	50~100	5.4	141.5	250	220
FI-180 Series	180	50	55~125	14	220.1	150	220
FI-220 Series	220	30	123~208	50.6	530.3	100	220
FE-224 Series	224	50	42~62	14.1	295.5	200	220
FI-224 Series	224	50	42	9.9	155.6	150	220
FE-263 Series	263	88	113~188	95	796.5	80	220
FI-280 Series	280	60	95~145	45	565.9	120	220
FI-300 Series	300	150	75	35	330.1	90	220
FI-375 Series	375	88	150~200	200	1257.6	60	220

Series	Types	RotorID	StatorOD	Stator installation pitch circle	Stator shieldOD	Overall thickness
10	Standard Compact	8/10 8/10	36 27	25 23	20	7
15	Standard Compact	12/13/15 12/13/15	40 32	30 28	25	7
20	Standard Standard Compact	6/8/10 15/18/20 18/20	45 45 37	36 36 33	30	7
25	Standard Compact	23/25	50 42	40 38	35	7
30	Standard Compact	28/30	55 47	45 43	40	7
35	Standard Compact	33/35	60 52	50 48	45	7
40	Standard Compact	38/40	65 57	55 53	50	7
45	Standard Compact	43/45	70 62	60 58	55	7
50	Standard Compact	48/50	75 67	65 63	60	7
55	Standard Compact	53/55	80 72	70 68	65	7

Series	Model	Inner rotorThread	Inner rotorMatch ID (H7)	Outer rotor Thread	Outer rotorMatch ID (H7)	StatorMatch ID (H7)
10-15-25	T-10-15-25	M10x0.4mm	9	M15x0.4mm	14	25
15-20-30	T-15-20-30	M15x0.4mm	14	M20x0.4mm	19	30
20-25-35	T-20-25-35	M20x0.4mm	19	M25x0.4mm	24	35
25-30-40	T-25-30-40	M25x0.4mm	24	M30x0.4mm	29	40
30-35-45	T-30-35-45	M30x0.4mm	29	M35x0.4mm	34	45