User manual

User Manual SCA-SS-70-10
7.3 Analog Inputs
+Set value –Set value: Inputs for Set Values
An external +10/-10 V analog signal for speed or for current is entered using +Set value and
–Set value inputs. If the effective voltage is 0V, the motor stops. If the effective voltage is
positive, the motor moves in one direction. If the input is negative, the motor consequently
will be move in the opposite direction.
These inputs are given in form of a differential amplifier, so each of them can be related to
ground. This offers the possibility to preset the level control in only one direction.
Additional information about the schematic refer chapter 3.2.
Range of Input Voltage -10 V to +10 V
Input Impedance 20 kOhm
Permanent Input Protection -30 V to +30 V
Remark:
To use the internal Offset potentiometer as Set value source set jumper J4 and
open jumper J5.
As an alternative, the set value can be entered using an external potentiometer (10 kOhm).
For this purpose, connect the slide resistance to +Set value, the left stop to -15V and the
right stop to +15V. This procedure requires the -Set value input to be bridged to GND.
The admissible range for the set value is limited by the programmed n max speed value. In
this case, the desired maximum speed can be selected according to the maximum input
voltage. If the motor does not stop at input voltage = 0 V, fine tuning has to be performed
using Offset potentiometer.
ElectroCraft
®
E-Mail: [e-mail] www.electrocraft.com May 2009
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