Omron TJ1-MC04 - PROGRAMMING 1 Programming Manual page 254

Examples and tips
The figure shows a general origin search scenario. This simple
origin search sequence has 3 steps:
1. Search for a signal.
2. Search for another signal.
3. Move the axis to a predefined position.
For safety reasons, limit switches are normally closed.
For this reason, in this figure and in the following figures
in this section, the low signal level is indicated as ON, and
the high signal level is indicated as OFF.
It is important to note that, before any homing procedure is
executed, it is necessary to set the axis parameters UNITS,
REP_DIST and REP_OPTION, and Servo Driver parameters
Pn202, Pn203 and Pn205 properly and in accordance with the
mechanical system and desired measurement units used in
programming. Those parameters have influence to the origin
search, especially if an absolute encoder is used. For more
information on setting these parameters, see section 6.1.2.
PROGRAMMING MANUAL
fig. 25
OFF ON OFF origin limit switch
moving part
min. limit switch ON OFF OFF ON
encoder
max. limit switch
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