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5.1.3 General attributes of the Position Sensor
Object
Attribute41:
Measurement status (Operating Status)
This attribute contains information on the various statuses
of the encoder.
Bit0 shows the current direction of movement. If the bit is
0 (FALSE), the position value is moving in a positive
counting direction. If it is 1 (TRUE), it is moving in a
negative counting direction.
Bit1 shows whether scaling is active. If this bit is deleted,
scaling is deactivated and BTL7-V50D-… outputs raw
values in this case. Scaling is activated if the bit is set.
Attribute42:
Measurement steps (Physical Resolution Span)
This attribute can only be read and it returns the number
ofphysical measurement counts over the nominal length
(inµm).
Attribute43:
Number of turns (Number of Spans)
The number of turns is shown here because the Position
Sensor Object is also valid for rotary encoders. For the
BTL7-V50D-…, the return value is always 1. The attribute
can only be read.
Attribute44:
Alarms (Alarms)
The attribute Alarms shows whether there is a malfunction
disturbing determination of the position value. The alarm
remains active until the error is rectified and the device
supplies a valid position value again. The only active bit
is the Flag Position Error. It is set if position determination
is not possible. This is the case, for example, if the
corresponding magnet is no longer in the measurement
range.
In the Flexible Magnet Mode all positions for a defined time
are invalid if the number of magnets changes. In this case,
the Position Error is also set.
5
Configuration and parameterization (continued)
5.2 Attributes of the device configuration object
General sensor settings are made in the device
configuration object. This is a manufacturer-specific object
with only one instance.
See Attributes of the device configuration object (class
100 (0x64)) in the appendix on page34 for an overview
of attributes.
5.2.1 Settings for synchronous operation
The BTL7-V50D-… can work in synchronous operation in
which internal measurements are triggered with clocked
synchronization. The time parameters must be set for this.
Activate CIP-Sync (Synchronous Mode)
If this BOOL is set to TRUE (1), the BTL7-V50D-… works
in synchronous mode. The parameters Synchronous
Period, Synchronous Shifttime and Synchronous Offset
must be correctly set for this, and control take place in the
correct timing from the point of view of the control system.
Synchronous Period, Synchronous Shifttime and
Synchronous Offset
Fig. 5-1: Timing synchronization
So-called Sync0 impulses are generated by an internal
timer for timing synchronization using CIP Sync. For
cyclical, timing synchronous operation, the BTL7-V50D-…
must know the expected Synchronous Period
(seeFig. 5-1).
Attribute4 Synchronous Offset can be used to move the
start of the internal measurement procedure in relation to
the Sync0 time. A further delay can be set in the internal
measurement process using Synchronous Shifttime.
Detection of the position takes place at this time.
In conjunction with the time for measurement
value processing and output, this results in the
Minumum Cycle Time.
The values of attributes 2 to 5 have the unit
nanoseconds (ns).
BTL7-V50D-…
Configuration Manual