ADLINK Technology cPCI-8168, Руководство пользователя

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Operation Theory 71
4.4.1 Original or home signal
cPCI-8168 provides one original or home signal per axis. This sig-
nal is used for defining the axes zero position. The logic of this sig-
nal must be set properly before performing a home procedure.
Please refer to the home mode section for details.
4.4.2 End-Limit switch signal
The end-limit switches are usually installed on both ends of an
axis. Plus EL must be installed at the positive position of the axis
and minus EL at the negative position of the axis. If the moving
part of a motor touches one of the end-limit switch signals, the
motion controller will stop sending pulses and will output an ERC
signal. The purpose of these two switch signals is to prevent the
machine from crashing during misoperation. If switches are
installed reversely, the protection will be invalid.
4.4.3 Slow down switch
The slow down signals can be used to force the command pulse to
decelerate to the starting velocity. This signal helps protect a
mechanical part moving at high speed from exceeding the mecha-
nism’s limit. The SD signal is effective for both plus and minus
directions.
4.4.4 Positioning Start switch
The positioning start switch is used to move from a specific posi-
tion when the machine is turned on. The function is demonstrated
in the diagram below.