NSD Varlimit VS-212DN User Manual

4-1
4. Function List
As shown below, the VS-212DN functions are divided into 2 groups consisting of 'main functions' and
'auxiliary functions'. The main functions are used by the VS-212DN for actual system control, and the
auxiliary functions are used to support the main function operations.
Function
Description
Main
Functions
Current position
detection function
The machine position is detected by the ABSOCODER sensor.
Limit switch output
function
The machine position which has been detected by the ABSOCODER
sensor is compared to the pre-
designated limit switch position, with
ON/OFF signal outputs being executed accordingly.
Positioning function
The machine position which has been detected by the ABSOCODER
sensor is compared to the pre-designated target stop position, with motor
control signals being output accordingly until the machine has been
positioned at the target stop position.
Auxiliary
Functions
Current position preset
function
When a misalignment occurs between the machine's actual position and
the designated current position value, this function is used to execute an
external signal input which automatically corrects the machine's position
according to a preset position value.
Current position hold
function
This function is used to store and read the current position value in the
buffer memory by detecting the leading edge of current position preset
input 1 or preset input 2 signal.
“Excessive current
position change”
detection function
Position detection is executed by the ABSOCODER sensor every 20ms,
and the difference between the previously detected current position value
and the present value is computed. The 'excessive current position
change' detection function is used to determine whether this difference is
within the permissible range prescribed by the parameter setting. If the
permissible range is exceeded, the error code “24” will occur.
“Excessive correction
amount” detection
function
When the 'current position preset' signal input occurs, the difference
between the machine's current position (which is to be corrected) and the
preset position value is computed. This function detects that difference
to determine whether it is within the permissible current position change
amount designated by the parameter setting. If the permissible range is
exceeded, the error code “23” will occur
“Upper limit over travel”
detection function
This function detects the current position detected by the ABSOCODER
sensor to determine whether it has exceeded the upper limit value (upper
limit of travel range) which has been designated by the parameter setting.
If the upper limit has been exceeded, the error code “20” will occur.
“Lower limit over travel”
detection function
This function detects the current position detected by the ABSOCODER
sensor to determine whether it has exceeded the lower limit value (lower
limit of travel range) which has been designated by the parameter setting.
If the lower limit has been exceeded, the error code “21” will occur.
Protected channel
function
This 'protected channel' function is used to prevent the setting data which
designates the limit switch output ON/OFF positions from being accidentally
changes during the course of normal operation.
The protected channel function can be canceled by setting the 'number of
protected channels' parameter to '0'. Data setting, change, and deletion
will then be possible in the same manner for all channels.
Speed detection function
This function is used to read rotation speed (r/min.) based on the current
position detected by the ABSOCODER sensor via DeviceNet.
Simple learning function
This function is used to enhance positioning accuracy by automatically
correcting the stop zone according to the discrepancy between the target
stop position and the cur
rent position upon completion of the previous
positioning.

NSD Varlimit VS-212DN Specifications

General

Brand	NSD
Model	Varlimit VS-212DN
Category	Controller
Language	English