Elgo EMAL Series, Operating Manual

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Product Features
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5 Product Features
The series EMAX / EMAL is an absolute length measuring system. Sensor and translator and interpolation unit
are together in the same compact housing. The magnetic tape of series EMAB is paste up to a plain area. The
EMAX / EMAL encoders can be mounted with a maximum distance of 1.5 mm to the magnetic tape. With a
reduced measuring accuracy the sensor distance can be up to 2.0 mm.
The only difference between EMAX and EMAL is the maximum measuring length:
 EMAX up to 10 m
 EMAL up to 20 m
SSI, CAN, RS232, RS422 and IO-Link are available as interfaces for the EMAX / EMAL sensors.
For more information about the interfaces see section
 8.
Typical applications are handling systems, conveyor and storage technology, hydraulic presses, stamping ma-
chines, casting machines, linear slides, linear drives and pick and place systems.
Two different designs are possible as sensor housings:
1. sensor housing with fixed cable outlet (see

6.2)
2. sensor housing with M9 round connector (see

6.3)
For versions with fixed cable outlet, a guide carriage and a guide rail are available (see accessories

12.2).
Overview of features:

no referencing required

direct wear free and contactless measurement

allowed distance range between sensor and magnetic tape: 0.1 ... 1.5 mm

Distance not ok = red LED on

measuring length up to 10 m (EMAX) resp. 20 m (EMAL)

high resolution 10 µm

repeat ac/- 1 increment

very resistant against dirt
5.1 Functional principle
A Hall sensor and a magneto-resistive impedance measuring bridge are guided over a two-track magnetic tape
with a fine-interpolation trace and an absolute track. Together with the sensor line the absolute track provides
an absolute value and the fine-interpolation trace provides together with the interpolation electronic the measur-
ing systems high resolution.
The fine interpolation track encloses alternately north- and south-pole tracks with a distance of 5 mm. These are
scanned with resistance bridges and provide a resolution of 0.01 mm. The absolute value provides the sensor
line with 16 single Hall sensors; these sensors are scanning the code sections of the north and south poles. The
absolute value on the magnetic tape recurs every 10 m with an EMAX resp. every 20 m with an EMAL system.
Figure 1: Coding of the magnetic tape
fine interpolation track
non-magnetized area
absolute track
N
S N S N S
N N N N S S S S N N N N S S S S N N S S
S N S N S
Magnetic tape EMAX / EMAL Cable outlet
fine interpolation track
non-magnetized area
absolute track
N S N S N S
N N N N S S S S N N N N S S S S N N S S
S N S N S
Magnetic tape EMAX / EMAL Round connector
Sensor with cable outlet:
Sensor with M9 round connector: