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53
command
Parameter
internal variable
monsrc
0 = position in closed loop
1 = reference input
2 = PID command voltage
3 = closed loop deviation including sign
4 = absolute closed loop deviation
5 = position in open loop
6 = actuator voltage
7 = actuator current
8 = actuator voltage NanoX
9 = actuator current NanoX
Upos[CL]
Uset
Uact
Uerr
Uerrabs
Upos[OL]
Upa1
Ipa1
Upa2
Ipa2
table 1: monitor source
! Please note the internal resistance of the monitor output. The electrical characteristics are shown
in chapter 16
0 (Upos[CL]) position voltage in closed loop, it means an actuator with 80
μm in closed loop
generates 0 to +10 V (= 8
μm/V or 0.125 V/μm)
1 (Uset)
the reference input, sum of the analog signal applied to the MOD input and the
digital value via set command
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 = Uset
– Upos
Uset = 0 to +10V
Upos = 0 to +10V
Uerr = -10V to +10V
To generate an output of 0 to +10 V the control deviation is divided by 2 and added by +5 V. To
calculate the control deviation back from the measured monitor voltage, take the following formula:
Uerr = (Umon
– 5V) * 2
Uerr = -10V to +10V
Umon = 0 to +10V
If the controller is properly adjusted the value is +5 V.
4 (Uerrabs) absolute closed loop control deviation:
|Uerr| = Uset
– Upos
|Uerr| = 0 to +10V
5 (Upos[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:
Upos(OL) = (Umon
– 2.5V) * 2
6 (Upa1)
the actuator voltage -20 V to +130 V of amplifier 1 converts to 0 to +10 V; to
calculate the actuator voltage 1 back from the measured monitor voltage, take the
following formula:
Upa1 = (Umon * 15)
– 20V
