3.1 Type code
Solid shaft
Type
S Solid shaft
Mechanical design
1
Servo flange, M4 thread, solid shaft Ø6 × 10 mm with face
D
Servo flange, M4 thread, solid shaft Ø6 × 10 mm with feather key
F
Servo flange, M3 thread, solid shaft Ø6 × 10 mm with face
G
Servo flange, M3 thread, solid shaft Ø6 × 10 mm with feather key
4
Face mount flange, M4 thread, solid shaft Ø10 × 19 mm with face
E
Face mount flange, M4 thread, solid shaft Ø10 × 19 mm with feather key
H
Face mount flange, M3 thread, solid shaft Ø10 × 19 mm with face
J
Face mount flange, M3 thread, solid shaft Ø10 × 19 mm with feather key
Electrical interface
O 4.5 … 32 V, SIN/COS
Connection type
Resolution
A M23 male connector, 12-pin, radial
B M23 male connector, 12-pin, axial
C M12 male connector, 8-pin, radial
D M12 male connector, 8-pin, axial
J Cable, 8-wire universal, 0.5 m
1)
K Cable, 8-wire universal, 1.5 m
1)
L Cable, 8-wire, universal, 3 m
1)
M Cable, 8-wire, universal, 5 m
1)
N Cable, 8-wire, universal, 10 m
1)
Periods per revolution
1
0
2
4
0
S
0
1
Stator coupling,
long (only with types B, T)
Resolution, 1,024 periods
D
F
S
6
0
S
-
S
O
0
1) The universal cable outlet is positioned so that it is possible to lay it
without bends in a radial or axial direction. UL approval not available.
Hollow shaft
Type
B Blind hollow shaft
T Through hollow shaft
Mechanical design
A Hollow shaft Ø6 mm with feather key groove
B Hollow shaft Ø8 mm with feather key groove
C Hollow shaft Ø3/8” with feather key groove
D Hollow shaft Ø10 mm with feather key groove
E Hollow shaft Ø12 mm with feather key groove
F Hollow shaft Ø1/2” with feather key groove
G Hollow shaft Ø14 mm with feather key groove
H Hollow shaft Ø15 mm with feather key groove
J Hollow shaft Ø5/8” with feather key groove
Electrical interface
O 4.5 … 32 V, SIN/COS
Connection type
Resolution
A M23 male connector, 12-pin, radial
C M12 male connector, 8-pin, radial
J Cable, 8-wire universal, 0.5 m
1)
K Cable, 8-wire universal, 1.5 m
1)
L Cable, 8-wire, universal, 3 m
1)
M Cable, 8-wire, universal, 5 m
1)
N Cable, 8-wire, universal, 10 m
1)
Periods per revolution
1
0
2
4
0
S
0
1
Resolution, 1,024 periods
Stator coupling,
long (only with types B, T)
D
F
S
6
0
S
-
0
0
0
1) The universal cable outlet is positioned so that it is possible to lay it
without bends in a radial or axial direction. UL approval not available.
4
Project planning
4.1 Requirements for signal evaluation
To determine the speed with the correct sign, as well as the correct incremental
position, both the sine signal and the cosine signal must be evaluated. This must
be carried out using a suitable safety architecture. Typically, the signal is evalu‐
ated on two separate channels, the results of which are compared with one
another during the process safety time
18
. The extent of the permitted deviation
must be selected to allow static errors to be detected in the evaluation.
18
Process safety time: Period of time between the point at which a failure that
could cause a hazard occurs, and the point by which the reaction must be
complete in order to avoid this hazard.
NOTE
Deviations can arise as a result of:
•
Pairing tolerances in switching thresholds:
± 1 increment
•
Pairing tolerances of sampling times: Number of increments in time dif‐
ference at maximum speed
The differential signals must always be used to evaluate the signals (see
).
Square-wave signals must be formed from the differential signals using suitable
switching elements (e.g., comparators). These square-wave signals are used for
counting by means of appropriate methods (e.g., a quadrature decoder).
The switching thresholds must be selected so that the lower limit of the vector
length monitoring (see
) is not exceeded. Accordingly, the upper
switching threshold – including tolerance – must be a maximum of 150 mV above
the center of the signal (see
) and the lower switching threshold –
including tolerance – must be a maximum of 150 mV below the center of the sig‐
nal.
WARNING
If the switching thresholds are not dimensioned appropriately and hysteresis
occurs during signal evaluation, this can cause additional signal edges to be
detected incorrectly or an incorrect failure to detect signal edges. This can
lead to the direction of rotation, position, or speed being determined incor‐
rectly, for example.
Using the counter, it is possible to achieve a resolution of 4,096 steps per rotation
(i.e., 4 steps per signal period or 1 step per quadrant of each signal period).
The diagnostic degree of coverage (DC) must be at least 99% to enable error
detection in the encoder signals. To achieve this, the diagnostic requirements
from
must be fulfilled. Diagnosis must be carried out within the
process safety time
18
.
4.2 Diagnostic requirements and error detection
In accordance with IEC 61800-5-2, the downstream evaluation system should
ensure the following diagnostic requirements are met and error detection is pro‐
vided; this is based on the error assumptions that the standard lists in relation to
the use of motion and position feedback sensors.
If an error is detected during one of the diagnostic processes listed below, an
error response must be initiated to bring the application into a safe state.
In the event of an error, the application must be brought into a safe state before a
hazardous situation can arise. The sum of the maximum time required for error
detection and the time for responding to errors must therefore be less than the
process safety time
18
.
The maximum time required for error detection is the interval during which the
diagnostic measures listed below are repeated in full.
4.2.1
Analog sine/cosine signal faults
To detect all impermissible level changes in the relationship between sine and
cosine, the underlying mathematical relationship between sine and cosine signals
is used.
By finding the variable
k
using the following mathematical formula
k² = k
1
² × sin²
α
+ k
2
² × cos²
α
or another suitable mathematical process, it is possible to determine the common
DC voltage level of both the sine and cosine signals. Comparing this with the cor‐
responding maximum and minimum limits enables impermissible deviations to be
detected quickly and precisely, regardless of the current angular position
α
.
The signals available can be used to determine
k
on the basis of the following cal‐
culation:
k² = (SIN+ – SIN–)² + (COS+ – COS–)²
This relationship between the useful signals can be illustrated clearly using a two-
dimensional model (Lissajous diagram). In this case, the useful signals form a
useful signal ring.
Where the signal
k
is concerned, a tolerance of ± 50% is permitted on either side
of the nominal position. A deviation that is greater than this indicates a violation
of the vector length limits. The evaluation system must respond to the error
accordingly.
To avoid false triggering, we recommend that you do not make the limits too
restrictive.
4.2.2
Loss of the encoder housing mechanical coupling or displacement of
the mechanical coupling during downtime or operation
In accordance with IEC 61 800-5-2, this error assumption can be ruled out if the
stator coupling or the face mount flange/servo flange has been mounted correctly
4.2.3
Loss of the encoder shaft/drive shaft mechanical coupling during down‐
time or operation
In accordance with IEC 61 800-5-2, this error assumption can be ruled out if the
encoder has been mounted correctly on the drive shaft (see
).
4.2.4
Sine/cosine signal downtime due to electrical defects
This error assumption can be ruled out as sine/cosine signals are detected and
processed in a purely analog manner, and the design does not provide for any
memory structures for analog voltages.
4.2.5
Measuring element (code disk) damage, contamination, or dissolving
Damage to or contamination on the measuring element can lead to the following
situations:
18
Process safety time: Period of time between the point at which a failure that
could cause a hazard occurs, and the point by which the reaction must be
complete in order to avoid this hazard.
8016866/12N8/2019-01-31/de, en, es, fr, it
DFS60S Pro | SICK
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