Selection Of The Braking Resistor - HEIDENHAIN TNC 410 M Technical Manual

3.5 Selection of the Braking Resistor

Procedure
Mathematical
formulas for
calculation
Data
Braking power P
Br
Braking energy E
Br
Mean value of the
braking power with a
specified alternation
of load P
M
Selection of the
braking resistor
April 2007
Calculation of braking power
Calculation of braking power with a specified alternation of load
Calculation of braking energy
Selection of the braking resistor according to
• Peak performance of the braking resistor
• Reliable mean value of the braking power
• Maximum braking energy of the braking resistor
Formulas
⋅ π ⋅ ⋅
2
M
Br
P = ------------------------------------------------- -
Br 60
⎛
2
⋅ ⋅ π ⋅
2
E = J
⎝
Br
t
1
⋅
--- -
P = P
M Br
T
≤
P P
Br max
≤
P P
M Mzul
≤
E E
Br max
Selection of the Braking Resistor
Variable
M : Braking moment [Nm]
Br
n
max
n
max
occurs [rpm]
J: Moment of inertia, including the motor
[kgm
n : Desired speed of the brakes [rpm]
2
n : Desired speed after braking [rpm]
1
2 2
n n
⎞ ⎛ ⎞
2 1
----- - ----- -
–
⎠ ⎝ ⎠
60 60
P : Braking power [W]
Br
t : Load time [s]
1
T: Cycle duration [s]
P
max
resistor [W]
P
Mzul
braking performance according to the
diagram as a function of E
example on page 3 – 16)
E
max
braking resistor [Ws]
: Maximum speed at which braking
2
]
: Peak performance of the braking
: Permissible mean value of the
: Maximum braking energy of the
[W] (see
Br
3 – 11