Key to the mechanical project planning procedures

Formula symbol	Unit	Description	Source
a_Bmax	m × s^-2	Maximum typical deceleration when braking
d₀	mm	Diameter of the output shaft transmission element	Application
cdf	%	Relative cyclic duration factor	Motor project planning
f_out	–	Application factor for checking the brake functions "Hold" and "Brake"	Braking torques Application factor fA
f_{Brake, output}	–	Design-dependent output factor	Design-dependent output factor fbrake,output Output factor fbrake,output
f_Mmax	–	Transmission element factor, braking torque, determination in relation to the used load range for braking work	Load ranges for horizontal and vertical applications Load range-dependent calculation coefficients fv, fMmin, fMmax
f_Mmin	–	Braking torque reduction factor, determination in relation to the used load range for braking work	Load ranges for horizontal and vertical applications Load range-dependent calculation coefficients fv, fMmin, fMmax
f_Notaus	–	Factor for determining M_aNotaus depending on the gear unit	Design-dependent output factor fbrake,output
F_R,Brems	N	Resulting gear unit load due to the radial load generated
F_Ra	N	Permitted overhung load on the output end for M_amax. Applies when the point of force application is at the center of the shaft end, or at the face end in the case of hollow shafts#	Product documentation
F_RaNotaus	N	Maximum permitted emergency off overhung load of the output shaft in combination with brake/BE.. safety brake. Applies when the point of force application is at the center of the shaft end, or at the face end in the case of hollow shafts.	Product documentation Design-dependent output factor fbrake,output
F_RP	N	Emergency off lateral force	Design-dependent output factor fbrake,output
f_V	–	Wear factor; determined based on the applied load range for braking work	Load ranges for horizontal and vertical applications Load range-dependent calculation coefficients fv, fMmin, fMmax
f_Z	–	Transmission element factor for the overhung load	Product documentation
i	–	Gear unit ratio	Product documentation
J_M	kgm²	Mass moment of inertia of the motor (incl. mount-on components), based on the motor shaft	Product documentation
J_G	kgm²	Mass moment of inertia of the gear unit, based on the motor shaft	Product documentation
J_L	kgm²	Mass moment of inertia of the application, based on the motor shaft	Application
K_J	–	Factor for external mass moment of inertia	Product documentation
K_M	–	Factor for load torque	Product documentation
K_P	–	Factor for static power and relative cyclic duration factor	Product documentation
L_B	h	Brake service life
M_amax	Nm	Limit value of the gear unit load capacity: maximum permitted output torque	Product documentation
M_aNotaus	Nm	Limit value of the gear unit load capacity: maximum permitted emergency stop torque in combination with BE.. brake/safety brake	Product documentation
M_B	Nm	Nominal braking torque for the BE.. brake/safety brake.	Product documentation
M_{brake, output}	Nm	Resulting gear unit load from the braking torque, based on gear unit output shaft	Product documentation
M_L	Nm	Static load torque at the motor shaft. • Horizontal + vertical upward: The efficiency of the application and the gear unit are taken into account as unfavorable factors. • Vertical downwards: The efficiency of the application and the gear unit are taken into account as favorable factors.
M_L,a	Nm	Static load torque value at the output shaft, efficiency not considered	Application
M_n	Nm	Nominal motor torque	Product documentation
M_P	Nm	Emergency off torque	Design-dependent output factor fbrake,output
N_B1	–	Number of cycles until brake maintenance in working brake operation
N_B2	–	Number of permitted emergency-stop braking operations until brake maintenance
N_B2max	–	Number of permitted emergency stop braking operations until end of service life	Consideration of mechanical service life limits
n_Brake	min^-1	For testing the relevant, real brake application speed
n_D	min^-1	Change in motor speed until brake application
n_m	min^-1	Relevant speed of the application referenced to the motor shaft	Application
n_max,0	min^-1	Maximum permitted operating speed of the brakemotor	Limit speeds for brakes Limit speeds nmax,0 and nmax,1
n_max,1	min^-1	Maximum permitted speed for brake application depending on application	Limit speeds for brakes Limit speeds nmax,0 and nmax,1
n_Nothalt	min^-1	Real emergency stop speed relevant for check
η_G	–	Gear unit efficiency	Product documentation
η_G'	–	Back-driving gear unit efficiency (for gear units with η_G < 90%)
η_L	–	Efficiency of the application	Application
P_N	kW	Nominal power	Product documentation
P_stat	kW	Static power	Motor project planning
s_Amax	m	Maximum typical stopping distance	Definition of terms
s_Bmax	m	Maximum typical braking distance	Definition of terms
t₂	s	Brake application time. Depending on the brake connection type, use t_2,I or t_2,II.	Pulse frequencies Pulse frequencies of the brakes
t_2,I	s	Brake application time for cut-off in the AC circuit (AC shutdown)	Pulse frequencies Pulse frequencies of the brakes
t_2,II	s	Brake application time for cut-off in the DC and AC circuit (AC/DC shutdown) as well as for DC-side disconnection (DC shutdown)	Pulse frequencies Pulse frequencies of the brakes
t_Bmax	s	Maximum typical braking time
t_Bmin	s	Minimum typical braking time
t_Signal	s	System signal propagation time	Application
t_cycle	s	Cycle time	Application
v_L	m × s^-1	Relevant speed of the load or application at the point in time when the emergency stop is requested	Application
v_Brake	m × s^-1	Real speed of the load or application when the service braking operation begins
v_Nothalt	m × s^-1	Real speed of the load or application when the emergency stop begins
W₁	J	Maximum occurring braking work during emergency stop
W_tot	J	Total braking work from all braking operations within the travel cycle
W_insp	J	Permitted work until brake inspection	Establishing the maintenance intervals Permitted braking work until maintenance
W_max	J	Maximum braking work W_n from all braking operations (in cycles n = 1, 2, 3, ..., n)
W_n	J	Occurring braking work in normal braking operations (in cycles n = 1, 2, 3, … , n)
W_per,n	J	Maximum permitted braking work for emergency stop depending on the emergency stop speed	Permitted emergency stop braking work Wper, n
W_per,Z	J	Permitted braking work depending on the number of braking operations per hour	Permitted braking work for service braking operations Wper,Z
X_B	–	Repeat accuracy of the braking and stopping distance in line operation	Load range-dependent calculation coefficients fv, fMmin, fMmax
Z	h^-1	Required cycle switching frequency	Application
Z₀	h^-1	No-load starting frequency of the motor	Product documentation
Z_B0	h^-1	Maximum permitted no-load starting frequency of the brake (without considering the motor)	No-load starting frequency for holding brakes No-load starting frequency and switching intervals for holding brakes
Z_B1max	h^-1	Maximum permitted emergency stop frequency of the brake in the selected load range	Limit speeds for brakes
Z_M	h^-1	Permitted switching frequency of the motor
Z_M,n	h^-1	Permitted switching frequencies of the individual acceleration phases
Z_M,cycle,per	h^-1	Permitted cycle switching frequency