maxon motor control
9
maxon motor
Operating Instructions
1-Q-EC Amplifier DEC Module 24/2
April 2015 Edition / document number 1002422_PDF_E - 04 / subject to change
Adjusting set values via PWM control
Instead of an analog voltage, a PWM signal with a fixed frequency and ampli-
tude can be used to adjust the speed set value.
The desired change in the set value is achieved by variation of the duty cycle
in the range 0…100%. Both the amplitude and the duty cycle have an influ-
ence on the resulting speed. The mean value of the applied PWM voltage
corresponds to the analog input signal for the speed set value.
Nominal value amplitude PWM set value 0…5 V
Max. value amplitude PWM set value
-28…+28 V
Frequency range PWM set value
500 Hz…20 kHz
Modulation PWM set value
0…100%
Continuous overvoltage protection
-28…+28 V
Examples:
motor type: 1 pole pair
speed range: 500...20‘000 min
-1
> @
> @
min
min
max
9
.
4
1
.
0
n
n
n
V
V
V
n
set
»
¼
º
«
¬
ª
PWM cycle 1: 33 % PWM @ 0 V … 12 V
à
4.0 V
à
16'020 rpm
t [µs]
Voltage [V]
0
2.5
5
7.5
10
12.5
-2.5
20
40
60
80
100
120
140
160
180
200
220
240
260
280
300
PWM cycle 1
PWM cycle 2
PWM cycle 3
PWM cycle 4
PWM cycle 5
PWM cycle 2: 60 % PWM @ 0 V … 10 V
à
6 V limited to 5 V (max. set value voltage)
à
20'000 rpm
PWM cycle 5: 90 % PWM @ 0 V … 2.5 V
à
2.25 V
à
9'056 rpm
PWM cycle 4: 50 % PWM @ 0 V … 5 V
à
2.5 V
à
10'051 rpm
PWM cycle 3: 75 % PWM @ -2.5 V … 7.5 V
à
5.0 V
à
20'000 rpm
