SIXpack 2 – Manual (V1.10 / January 29
th
, 2010)
17
5.5.1
Types of reference point definitions
The SIXpack 2 provides two completely different types to define the reference point:
Mechanical stopper for reference point (linear axis only)
At start point or end point a stopper for the mechanic of the axis is build in. At reference search the
SIXpack 2 moves the respective axis in direction of the stopper (defined by the flag MT_NULLLEFT, SQPack-
tab: “Reference search”, CMD $15) for a distance of
Poslimit
* 5/4. The multiplication with 5/4 causes the
SIXpack 2 to reach the stopper before end of the reference search. The motor is mechanically stopped,
reference point is reached.
Electrical reference point
At any point of the positioning scale of the axis an electrical switch is implemented which is activated by
the passing motor. The SIXpack 2 catches this for reference point.
A reference switch attached one end of a linear axis can be used as end switch. At activation of the switch
the motor stops.
5.5.2
Hardware installation
5.5.2.1
Connection of electrical reference switch
The reference switch is connected to the pins „Ref_In“ and „GND“. Optionally a series resistance of about 2.2kOhms
can be inserted to match EMC demands. In general using an opener, i.e. a normally closed switch is advisable. So
broken cables can be detected. The reference input is equipped with a Schmitt-trigger.
SIXpack 2
Ref_in
GND
opener switch
2k2 Resistor
(optional)
Figure 5.8: Connecting reference switch
