Balluff BML-S1G0 Serie Notice D'utilisation D'origine page 56

BML-S1G0-_7_ _-M5E_-_0-_ _
Absolute Magnetically Coded Position Measuring System
7
Diagnose (continued)
If the BEF number declines significantly anywhere in the
measuring range, the magnetic tape and sensor head
should be inspected at this position (mounting tolerances,
magnetizable material, see section 4.1.1).
Error Possible cause
BEF number too Leaving the valid working range,
low over a range gap Z, offset Y, angle
Magnetic tape damaged
Magnetic or magnetizable material nearby
Tab. 7-1: Possible causes/elimination for a lowered BEF number
The BEF number can be used as a setup aid during
startup or for maintenance work using the BML
Configuration Tool (see section 10.5 on page 30). In
addition, the number can be monitored permanently by the
controller. Then, changes to the system can be detected
immediately (preventive maintenance).
The BEF value is transferred in the diagnostic data with 4
bits of an 8-bit word (see Tab. 7-1).
Bit 7 Bit 6
Diag MSB
BEF3 BEF2
BEF MSB
BEF number
Tab. 7-2: Structure of the diagnostic data
These optional values are transferred via the SSI and
BiSS interface. Nevertheless, both interfaces are
compatible with the standard SSI interface and BiSS-C
interface. The controller can query and evaluate the value.
In the following, it has been assumed that n data bits and
8 diagnosis bits are transferred. The parameter n is defined
in the BML. With SSI, it can assume different values and is
selected via the order code.
22 english
Troubleshooting
Adjust the sensor head (see sec. 4 starting page 9).
Exchange magnetic tape.
Note the restricted area for magnetizable material (see sec. 4
starting page 9). Identify and replace this material.
Bit 5 Bit 4
BEF1 BEF0
BEF LSB
Bit 3 Bit 2
X X
not relevant
Bit 1 Bit 0
Diag LSB
X X