Function; Reference Point Function; Error Signal Bml-S2C0 - Balluff BML-S2C0-Q-M6-0-KA/KF Serie Manual De Instrucciones

BML-S2C0-Q _ _ _ -M6 _ _ - _ 0-KA _ _ /KF _ _ /KA _ _-S284
Incremental Magnetic Linear Encoder
3
Construction and function (continued)
3.2

Function

The BML is a magnetically coded, non-contact,
incremental position measuring system consisting of a
sensor head and magnetic tape. The sensor head and
magnetic tape are mounted on the machine. The magnetic
tape contains alternating north and south poles.
The two incremental sensors in the sensor head measure
the magnetic alternating field. Moving without any contact
over the magnetic tape, the two incremental sensors in the
sensor head sense the magnetic periods, allowing the
controller to detect the travel range.
– To function correctly, the bottom of the
sensor head must always be above the
magnetic tape (see Distances and tolerances
on page 9).
– For a complete technical description and
assembly instructions for magnetic tapes,
please see the magnetic tape user's guide at
www.balluff.com/downloads-bml.
The system is available in several variants:
– With or without pole-periodic reference point signal
– With or without error signal
Not all variants cover the illustrated functions
and deviations from the illustrations shown may
occur.
3.3

Reference point function

For every incremental position measuring system, the
reference position is the indispensable starting point for
counting.
The way the reference position is detected depends on the
sensor head, the magnetic tape, and the controller.
LED: red
Sensor head
out of range
Fig. 3-3: Error signal BML-S2C0-...-M6_4-...
8 english
No or pole-periodic reference signal:
System consisting of:
– BML-S2C...-M60_-... (none) or
BML-S2C...-M62_-... (pole-periodic)
– BML-M...-I6_-...-R0000 magnetic tape
The sensor head detects the magnetic periods using the
incremental sensors. The magnetic tape contains a track
with magnetic north and south poles. The position is
detected by the controller by adding up the counted
increments.
With the pole-periodic reference point signal, a reference
point signal is output with each magnetic pole, i.e. every
10 mm. In this case, an external reference switch must be
set at the selected reference point signal. The controller
evaluates the reference position at the moment when the
switch and the reference point signal from the sensor head
are active.
3.4 Error signal BML-S2C0-...-M6_4-...
The sensor head is equipped with additional amplitude
monitoring. As long as the sensor head is within its
function range, the error signal (Nerror) is HIGH. If the
sensor head is not on the magnetic tape or considerably
outside of its function range, then the error signal is LOW.
LED
Green
Red
LED: green
Normal function
Sensor head within the function range.
Error signal (Nerror)
Sensor head is located outside the
function range.
LED: red
Distance too great (outside the
function range)