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example 2:
This example shows the sequence of the commands to move the actuator with the NPC120
from the minimal position 0µm to 35,46µm:
command
response
content
[Enter]
NPC120SG
after pressing the [Enter] key on the computer keyboard the
prompt shows “NPC120SG>” in the HYPER TERMINAL
program
setk,1
none
activates the remote control
cloop,1
none
switches to closed loop mode
set,35.46
none
set the actuator to 35.46µm
rk
rk,35.460
displays the set value
chart 4: example for remote control NPC120[SG]
8.3.5 Calibration of Encoder
The encoder of NPC3 [SG] e.g. NPC120 [SG] is used for the calibration of the attached
actuator in open and closed loop. The encoder has a resolution of 30 detent / rotation.
With each step of the encoder an internal counter (
EncIncre
) within the scanning interval (
SI
),
will be incremented or decremented, depending on the direction of rotation. After scanning
interval the NPC3[SG] calculates a new stroke (
) or voltage (
deltaValue
), depending on the
mode (
EM
). The actuator will be charged with this calculated value.
EncIncre
will be clear the
encoder and the procedure start again.
The values of the encoder can be analyzed by 3 different modes (
EM
):
normal with acceleration (
EM0
)
calculation deltaValue:
deltaValue = EncIncr
EncExponent
adjustable interval (
EM1
)
calculation deltaValue:
deltaValue = EncStep
adjustable interval with acceleration (
EM2
) calculation deltaValue:
deltaValue = EncIncr * EncStep
encoder commands generally:
call: encmode,<0 to 2>
example: encmode,1
answer: none
the mode of encoders is set to EM1
(adjustable interval)
call: enctime,<0 to 255>
example: enctime,2
answer: none
scanning interval (SI) is set to 0.04 sec
Scanning interval (
SI)
can be adjusted in a range between 0 and 5.1sec with a step size of
0.02 sec. The evaluation of the encoder will be done in this time period. In each interval only
one encoder can be evaluated!
This means, if you have 3 active channels and an adjusted
interval of 1 sec. the encoder will be scanned in an interval of 3 seconds.
call: enclim,<1...65535>
example: enclim,10000
answer: none
the step limitation is set to 10000
If the absolute value of
deltaValue
is higher than enclim,
deltaValue
will set to enclim with the
same prefix.
The above-named commands are valid for all modes.
