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Motor Selection Guide

Basic DATA for Calculation

Total weight of table & work	W =	kgf
Total mass of table & work	m =	kg
Table External Diameter	D₀ =	cm
Table Inner Diameter	D₁ =	cm
Table Turning(Rotation) Angle	Θ =	˚
Positioning Time	t₀ =	sec
Time of Acc/Dec	t₁ =	sec
Gravitational acceleration	g =	m/sec²

External Force	F_E =	kgf
External Force Action Angle	a =	˚
Radius to point of application of external force	r_E =	cm
Gear Ratio	R =	Without Gearbox R=1
Gear Efficiency	_ηR =	90%(without Gearbox _ηR=1)
Safety Ratio	S =
Bearing Coefficient of Friction	μ =

If you enter values in the yellow fields, the rest of the values are calculated automatically.

Refresh Calculate

Operation Speed and Acceleration Calculation

Index Table Rotaion Angular Velocity ω_T = (Θ × π / 180) / (t₀-t₁) = rad/sec
Index Table Rotaion Velocity ω_T = {(Θ / 360) / (t₀-t₁) } × 60 = rpm
Operation Motor Revolution Angular Velocity ω_M = ω_M × R = rad/sec
Operation Motor Rotaion Velocity = ω_M = (ω_M × R) / 2π × 60 = rpm
Operating Motor Resolution Angular Acceleration = ω =	ω	=		= rad/sec²
	t₁

Motor Selection


Just consider Rotor's Inertia Moment as J₀ = 0,
Motor Operation Torque	T_M =	so, from FASTEH Motor Torque curves
Operating motor revolution velocity	ω₈ =	rpm at
Operating Torque is	T_M =	Select motor offers over N.m from curves

See Torque Curves of Selected Motor

Verify validation of selected motor


From selected motor spec, need to file out inertia moment J₀
J₀ = gcm² = kgcm² = kgm²
Motor's operating Torque re-calculation with consideration of motor inertia moment
T_M = × J₀ + kgf·cm
= × + = kgf·cm
= N·m

[ Verify validation of selected motor ]
From selected motor's torque curve
Selected motor's revolution velocity	ω₈ =	rpm at
Selected motor's torque is	T_M =	is over : OK.
Selected motor's torque is	T_M =	is less than : NG.
Repeat step 6. (Motor selection) and Step 7. (Verify Validation) width increasing motor's length or size

Refresh Calculate

Verify validation of selected motor


K =	J_L	=		=
	J₀ × R²		× ²

If Load's intertia moment ratio is less than 30, result is OK.
Can operate but motor's inappropriate opation (vibrating at Acc/Dec) can be happened So, please input enough Acc/Dec and need to decrease operation speed If you can't control Acc/Dec and need to decrease operation speed, please increase one level of motor's length or size, We would like to recommend to choose bigger motor has higher inertia moment. In case of using reducer, even selected motor's operation torque is enough but load inertia moment ratio "K" is not satisfied, We would like to recomment to choose incrased ration of reducer.