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commands). In function generator mode the modulation input is permanently switched off.
monitor output: MON
With a special command, many different signals can be shown. The voltage range of
0…+10 V is
available at this socket and can be monitored by using an oscilloscope. Pay attention to the inner
resistance of the monitor output.
Command
Description
Display
Value
MON
monitor output
(default = 0)
Umes/CL
Udes
Uact
Uerr
Uerrabs
Uout
Umes/OL
0 = position in closed loop
1 = reference input
2 = PID command voltage
3 = closed loop deviation including sign
4 = absolute closed loop deviation
5 = actuator voltage
6 = position in open loop
table 2: monitor
0 (Umes/CL) position voltage in closed loop, it means an actuator with 80
μm in closed loop
generates 0...+10 V (= 8
μm/V or 0.125 V/μm)
1 (Udes)
the reference input, sum of the analog signal applied to the MOD input, the digital
value by the OFFSET potentiometer, and the digital value from the EDS2 via
CAN-Bus
2 (Uact)
output of the controller, set value for the power amplifier
3 (Uerr)
closed loop control deviation including sign: the value can be positive or negative:
Uerr = Ucom
– Umes
Ucom = 0...+10V
Umes = 0...+10V
Uerr = -10V...+10V
To generate an output of 0...+10 V the control deviation is divided by 2 and +5 V is added. To
calculate the control deviation back from the measured monitor voltage, take the following formula:
Uerr = (Umon
– 5V) * 2
Uerr = -10V...+10V
Umon = 0...+10V
If the controller is properly adjusted the value is +5 V.
4 (Uerrabs) absolute closed loop control deviation:
|Uerr| = Ucom
– Umes
|Uerr| = 0...+10V
5 (Uout)
the actuator voltage -20 V...+130 V converts to 0...+10 V; to calculate the actuator
voltage back from the measured monitor voltage, take the following formula:
Uactuator = (Umon*15)
– 20V
6 (Umes/OL) The position voltage in open loop (OL) is greater than in closed loop. The monitor
voltage would be smaller than 0 V and greater than +10 V. The value gets adjusted.
To calculate the open loop position voltage back from the measured monitor
voltage, use the following formula:
Umes(OL) = (Umon
– 2.5V) * 2
