MRMC MRMC-2118-00, Быстрый старт

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Round Rail Quick Start Guide
28
Mounting the Limit Switch and Datum Switch
magnets on the rack
About track limits
In a track-mounted rig there are typically three devices for limiting
movement along the track to prevent the rig going off the end of the
track:

Soft limits - You configure these in the Flair Motion Control
Software that controls the rig. When the system is working
correctly the soft limits act as a barrier to other parts of the
software such as programmed moves or live commands, so that
no part of the software can move the rig beyond the soft limits.

Limit and Datum Switches - The Limit Switch consists of a
magnetic sensor located on the track motor pinch wheel on the
underside of the rig, and two magnets which you mount at
each end of the rack. The position of the magnets along the
rack defines the ultimate limits, along the track, for the rig
electronics. You define the soft limits within the range of the
Limit Switch magnets, so that if the soft limits fail for some
reason and the rig reaches one of the Limit Switch magnets, the
system electronics automatically shut down any further
movement and apply the brakes. A similar switch called the
Datum Switch is used in combination with a single Datum
magnet which you also mount on the rack but at a different
distance from it. The Datum Switch defines a fixed reference
point on the track for the electronics. The Flair software can
then use this position as the home position or zero point, from
which all movements and soft limits along the track are
measured.

Buffers - These are steel plates that physically prevent the rig
from going off the end of the track if the previous two limits
fail. Spring-loaded bumpers on the rig help to prevent damage
to the rig or track, but you should never intentionally use the
buffers to stop the rig.
Mounting the magnets
Although you can mount the magnets for the Limit Switch and Datum
Switch on the rack at any time, you ordinarily do this after mounting the