Absolute Quadrature Interface - Balluff BML-S1G0-7-M5E-0 Serie Manual De Instrucciones

BML-S1G0-_7_ _-M5E_-_0-_ _
Absolute Magnetically Coded Position Measuring System
6
Interfaces (continued)
6.3

Absolute quadrature interface

The absolute quadrature interface is a digital A/B/Z
interface that is compatible with an incremental interface.
The inputs/outputs/parameters have the following data:
Inputs Name in the
interface document
+VH Req
–VH Req
Preset
Tab. 6-8: Inputs
Outputs Name in the
interface document
+A, –A
+B, –B
+Z / +VH Busy, Z / VH Busy
–Z/–VH Busy
Tab. 6-9: Outputs
Can be configured with the BML Configuration Tool BAE PD-ML-010-03
1)
(section 10.5). If the VHReq input is used, the customer circuitry must
ensure that the input is not incorrectly activated. Therefore the input may
not float.
The input should also not bounce.
In case of an error, the BML outputs become high impedance. The
2)
controller may interpret this as a cable break.
For the relationship between the min. edge
separation, resolution and max. speed see
Tab. 6-15 and Tab. 6-16 on page 20.
Times
Designation Value
t 0.1 ms
VHstart_delay
The edges can occur with the minimum edge separation.
Resolution and minimum edge separation must be
specified when ordering (see section Type code on
page 31).
Both values can be set with the BML Configuration Tool
(see sec. 10.5).
If the sensor is supplied with voltage that is
isolated from the processing electronics, the
GND for this voltage must be connected to the
GND of the processing electronics.
18 english
Physical
layer
VH Req RS422
Preset 0/5...28 V
Physical
layer
A RS422/
RS485
B RS422/
RS485
RS422/
RS485
Explanation
Time between the low-
impedance state of the
outputs and the start of the
virtual reference run
The absolute quadrature interface is described
in the document Interfaces for BML
Magnetically Coded Position Measuring
System (Doc. No. 929191). The document is
part of this guide and must be used.
Shown in interface Configurable/
document as high factory default
+VH Req > –VH Req Yes / not active
24 V No / activated
Error value Configurable/
2)
factory default
Tristate No/activated
Tristate No/activated
Tristate
Input VH Req is implemented as a differential input (RS422)
in the sensor head (BML). If a controller (PLC) does not
support this output, an RS422 converter should be used. If
this is not possible, a circuit which simulates a differential
signal for the sensor head can be used. Since it would not
be an actual differential signal, the circuit must be more
sensitive to EMC interference. This must be taken into
account in cable routing, cable length etc.
Dig Out
24 V/0 V
24 V
GND
FLC
Fig. 6-1: Suggested circuit for 24 V – RS422 adaptation
The following resistances should be selected:
R1 = 42 kOhm
Reduces for +VH Req the 24 V/0 V to
4.6 V/0 V.
R4 = 10 kOhm
R2 = 91 kOhm
Reduces for –VH Req the 24 V to
2.4 V.
R3 = 10 kOhm
Duration for high
1)
100 µs < t
VH
> 0.5 s
1)
Yes / Z
R1 5 V/0 V +VH Req
R2 2.5 V –VH Req
BML
< 1 s