maxon motor
1-Q-EC Amplifier DEC 50/5
Operating Instructions
5.1.5 “/Brake”
function
If the input is not wired or the applied voltage is greater than 2.4 V, the /brake
function is deactivated.
If the input is placed at Gnd-potential or the applied voltage is lower than 0.8 V,
the /brake function is activated and the motor shaft slows down to a halt, short-
circuiting the motor windings. The motor windings remain short-circuited until
the /brake function is deactivated.
The /brake function is also used with an active /disable function.
The “/Brake” input is protected against overvoltage.
Input voltage range
0 ... +5 V
Input
impedance
33 k
Ω
pull-up resistor at +5 V
Continuous overvoltage protection
-50 ... +50 V
Max. brake current
30 A
Delay time
approx. 12 ms
“/Brake” inactive
Input open or
input voltage > 2.4 V
“/Brake” active
Set input to Gnd or
input voltage < 0.8 V.
The maximum permitted brake speed is limited by the maximum permitted
short-circuit current and maximum kinetic energy:
•
I <= 30 A
•
W
k
<= 20 Ws
the values can be calculated as follows:
max. permitted brake
speed limited by brake
current
(I = 30 A)
The maximum permitted brake speed can be calculated from the
motor data:
(
)
]
[
05
.
0
30
max
rpm
R
k
A
n
Ph
Ph
n
Ω
+
⋅
⋅
=
−
k
n
= Speed constant [rpm/V]
R
Ph-Ph
= Terminal resistance phase-phase [
Ω
]
max. permitted brake
speed limited by kinetic
energy (W
k
= 20 Ws)
With the given moment of inertia, the maximum speed can be determined
using the following formula:
]
[
000
10
365
max
rpm
J
J
n
L
R
⋅
+
=
J
R
= Rotor inertia [g
•
cm
2
]
J
L
= Load inertia [g
•
cm
2
]
10
maxon motor control
October 2008 Edition / Doc.No. 544910-06 / subject to change
