Interfaces - Balluff BML-S1A-Q/A-M-0-S184/KA Serie Manual De Instrucciones

BML-S1A_-Q/A_ _ _-M_ _ _-_0-S184/KA_ _
Linear Position Encoder
5 Wiring (cont.)
5.4

Interfaces

Analog incremental measuring
system
The sensor sends the measured
variable to the controller as an ana-
log sine-cosine differential signal
with an amplitude of approx. 1 Vpp
(peak-to-peak value) in the nominal
range. The period is 1 mm. The
signals remain low-frequency even
during rapid movement. To ensure
noise-free transmission, the
permissible maximum cable length
is 20 m.
Signal period 360° el.
Fig. 5-3: Analog output signals
A channel
B channel
Reference
channel
Fig. 5-4: Following electronics
circuit for analog output
12
english
Digital incremental system
The sensor transmits the measured
variable to the controller as a digital
differential voltage signal (RS422).
The edge separation A/B
corresponds to the resolution of the
sensing head.
Fig. 5-5: Digital output signals
Reference
mark
el.
Fig. 5-6: Following electronics
circuit for digital output
Signal period 360° el.
Edge separation
Reference pulse
el.
A channel
B channel
Reference
channel
Fig. 5-8: Limit switch circuit
Fig. 5-9: Limit switch signals
Circuit for reference position
Depending on the model, the
sensor sends either no reference
signal, a pole-periodic reference
signal, a single reference signal, a
fixed periodic or a distance coded
reference signal. The width of
the reference signal for the digital
BML-S1A_-Q is always one
increment. With the analog
BML-S1A_-A the width of the
reference signal is approx. 1/2 a
period, i.e. 0.5 mm.
For periodic reference points an
external reference switch must be
installed at the selected reference
point position.. The controller must
link both signals as shown in
Fig. 5-7. The accuracy requirements
of this switch are not especially
high.
Note: The reference signals from the
limit switch area are not allowed to
be processed.
External switch
Fig. 5-7: Ref. position circuit
Circuit for limit switches front and
back
The opposite poled permanent
magnets at the ends of the
measuring range are each sensed
by a limit switch sensor.
The sensors have a normally closed
function to GND, so that cable
break can be detected.
Rear limit switch
Front limit switch
Reference
signal
for the
controller
Controller
Front limit
switch
Rear limit
switch