SMC Networks LECSB2-T Series User Manual

12. ABSOLUTE POSITION DETECTION SYSTEM
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12. ABSOLUTE POSITION DETECTION SYSTEM
CAUTION
If [AL. 25 Absolute position erased] or [AL. E3 Absolute position counter warning]
has occurred, always perform home position setting again. Otherwise, it may
cause an unexpected operation.
If [AL. 25], [AL. 92], or [AL. 9F] occurs due to such as short circuit of the battery,
the battery can become hot. Use the battery with case to prevent getting burnt.
POINT
Refer to section 12.9 for the replacement procedure of the battery.
When absolute position data is erased from the encoder, always execute home
position setting before operation. The absolute position data of the encoder will
be erased in the followings. Additionally, when the battery is used out of
specification, the absolute position data can be erased.
The encoder cable was disconnected.
The battery was replaced when the control circuit power supply was off.
If the following parameters are changed, the home position will be erased at the
next power-on. Execute the home position return again after power-on.
[Pr. PA06 Electronic gear numerator (command pulse multiplication
numerator)]
[Pr. PA07 Electronic gear denominator (command pulse multiplication
denominator)]
[Pr. PA14 Rotation direction selection/travel direction selection]
[Pr. PT08 Home position return position data]
[Pr. PT28 Number of stations per rotation]
12.1 Summary
12.1.1 Features
For normal operation, as shown below, the encoder consists of a detector designed to detect a position
within one revolution and a cumulative revolution counter designed to detect the number of revolutions.
The absolute position detection system always detects the absolute position of the machine and keeps it
battery-backed, independently of whether the servo system PC or PLC...etc power is on or off.
Therefore, once home position return is made at the time of machine installation, home position return is
not needed when power is switched on thereafter.
Even at a power failure or a malfunction, the system can be easily restored.
12.1.2 Restrictions
The system cannot be configured under the following conditions. Additionally, test operation cannot be
performed in the absolute position detection system. To perform test operation, select incremental
system in [Pr. PA03].
(1) Speed control mode and torque control mode
(2) Control switch-over mode (position/speed, speed/torque, and torque/position)
(3) Stroke-less coordinate system, e.g. rotary shaft, infinitely long positioning
(4) Changing electronic gear after home position setting.
(5) Using alarm code output.
(6) Using incremental value command method ([Pr. PT01] = "_ _ _ 1").

SMC Networks LECSB2-T Series Specifications

General

Brand	SMC Networks
Model	LECSB2-T Series
Category	DC Drives
Language	English