ABB ACS55, User Manual

Page: 20 / 270

20 EN
Speed controlling
The analogue input gives the speed (frequency) reference for ACS55. The correspondence between the analogue input and the
reference depends on the settings of the DIP switches as shown below. Output frequency follows the reference changes as defined by
the ACC/DEC potentiometer.
High frequency mode OFF (default) High frequency mode ON
DIP switch settings:
HI FREQ = OFF
AI OFFSET = OFF (curve a) or ON** (curve b)
MOTOR NOM FREQ = 50 or 60 Hz DIP switch settings:
HI FREQ = ON
AI OFFSET = OFF (curve a) or ON** (curve b)
MOTOR NOM FREQ = 50 or 60 Hz
The output frequency is limited to the selected
nominal frequency of the motor. Actual output frequency is limited to a value between f
N
and f
N
+ 70 Hz by the
HI FREQ potentiometer. The potentiometer does not affect the scaling of the
analogue input.
* Use AI jumper to select voltage or current signal. See page 18 .
** To protect the drive against analogue input signal loss, the drive trips if the signal value is below 2 V (4 mA).
f
Input*
10 V
f
N
[V, mA]
0
2 V
4 mA
a
b
20 mA
f
Input*
10 V
[V, mA]
0
f
N
+ 70 Hz
frequency reference
f
N
output frequency limit
2 V
4 mA
a
b
20 mA