A loss of sender masking will result in the maximum signal level being reached on
both channels. This can be detected in accordance with
.
If the code disk is not aligned correctly in relation to the optical scanner or if cont‐
amination is present, this will also result in a signal level on the sine and cosine
channels, which can be diagnosed according to
.
In accordance with EN ISO 13 849-1 and EN ISO 13 849-2, errors that occur as a
result of the measuring element dissolving can be ruled out due to the mechani‐
cal over-dimensioning.
4.2.6
Oscillation of one or more outputs
Oscillation at the signal outputs can be detected as follows:
If the oscillation leads to impermissible signal levels in one or both channels, then
error detection as per
can be used.
During downtime, and when using a suitable phase discriminator for generating
counting pulses in the evaluation system, oscillation of an input signal will result
in counting up and down for an increment. The error resulting from this corre‐
sponds to the angular value of one increment.
Oscillation of both signals (sine and cosine) in the phase or of an individual signal
while the motor is running will lead to impermissible signal levels which are
detected using measures in accordance with
4.2.7
Swapping of the sine and cosine output signals
This error can be ruled out as the sine/cosine signals are detected and processed
separately.
The encoder does not use any multiplexers for these signals.
4.2.8
Monitoring the encoder supply voltage output by the evaluation system
Impermissible encoder supply voltage levels are detected using the measures
described in
Analog sine/cosine signal faults
. The lower limit for the vector length
specified there is particularly useful for undervoltage monitoring.
To contain errors from common causes and enable early error detection, the sup‐
ply voltage of the encoder must be monitored to ensure that it complies with the
limits specified in the technical data.
4.2.9
Operating the encoder system outside the permissible temperature
ranges
If it is not possible to ensure that the encoder system will be operated within the
permissible temperature range, the system operator must take suitable measures
to ensure that the specified temperature range is complied with.
Errors resulting from operation at impermissible temperatures are detected using
the measures described in
.
4.3 Requirements for the mechanical shaft connection
4.3.1
Hollow shaft encoder
The drive unit must be connected to the hollow shaft encoder using a high force
clamp connection or a form-fit and a high force clamp connection. Using a feather
key will prevent the encoder from being twisted radially.
A feather key must be used for drive shafts with a diameter of 6 mm, 8 mm, and
3/8”. This ensures that the over-dimensioning required to rule out errors caused
by the loss of the shaft connection.
To find out the requirements for mounting the feather key on the drive shaft,
refer to the dimensional drawings at the end of the operating instructions on
the language-neutral supplementary sheet.
4.3.2
Face mount flange encoder and servo flange encoder
The shaft coupling is part of the safety-related function chain and must be dimen‐
sioned and validated accordingly by the user. It is not an integral part of the safety
assessment carried out by SICK STEGMANN.
Connect the encoder and the drive system using a flexible coupling.
Use a coupling that is suitable for the application. Couplings must comply
with the requirements specified in IEC 61 800-5-2:2008 (see
Observe the technical data and mounting instructions of the coupling used.
The following mechanical designs are available for a positive connection (see
dimensional drawings at the end of the operating instructions (on the language-
neutral supplementary sheet)):
•
Solid shaft with feather key
•
Solid shaft with face
5
Mounting
This chapter describes how to prepare and mount the DFS60S Pro.
Switch off the power of all affected machines/systems during the mounting
process.
Avoid any blows or impact to the shaft to prevent damage to the ball bear‐
ings.
Never pull or push on the encoder.
5.1 Mounting material
You will need the following screws:
•
For the stator coupling:
–
4 × M3 cheese-head screws in accordance with ISO 4762 (or equiva‐
lent screw types with even connecting surface)
–
Washers
•
For flange variants F, G, H, J
–
3 × M3 screws
•
For flange variants 1, D, 4, E
–
3 × M4 screws
•
For mounting the servo flange
–
Large servo clamp accessory set
(part no. 2029166)
–
3 × M4 screws
The property class of the screws must be at least 8.8. Select the length of the
screws in accordance with the installation conditions.
5.2 Preparation for mounting
Ensure that the mounting parts are free from lubricant and contamination.
Look out for any damage that may be present.
In the case of stator coupling variants, only rigid shaft connections may be
used, they must not be elastic (such as bellows couplings).
5.2.1
Generally applicable notes
Connect the DFS60S Pro to the flanging supplied by the customer in a way that
prevents it from rotating.
All dimensions and tolerances specified in the technical drawings and the mount‐
ing instructions must be complied with.
The more precise the centering for the DFS60S Pro, the lower the angle and shaft
offset during mounting and the lower the load on the bearings of the DFS60S Pro.
All screw connections must be secured against loosening with liquid screw adhe‐
sive (LOCTITE 243, for example).
NOTE
Spring washers and toothed washers are not sufficient for securing screws.
For variants with a stator coupling, it may not be possible to hold the torque
wrench perpendicular to the screw. An angle of inclination of up to 20° is included
in the tightening torque tolerance. Loosening or securing the screw at an angle on
a regular basis can cause damage to the screw (see
).
5.2.2
Mounting a hollow shaft encoder with a stator coupling
If necessary, mount the feather key (1) supplied on the drive shaft (2) pro‐
vided by the customer (observe
).
Block the customer's drive shaft (2).
Apply screw adhesive (observe
) to the thread of the clamping
ring (3) or the Torx T20 screw (4) supplied.
Insert the Torx T20 screw (4) in the clamping ring (3) and secure it loosely;
do not tighten it at this stage.
Push the encoder onto the customer drive shaft (2), aligning it with the
feather key (1). Ensure that you take the distance between the stator cou‐
pling (5) and the mounting surface (6) into account when it comes to the
length of the screws (7).
Secure the screws (7) and the washers (8) loosely and apply screw adhesive
(observe
) to each thread at the same time.
Screw in the screws (7) until the encoder can be fully pushed on and the sta‐
tor coupling (5) is resting against the mounting surface (6).
Tighten the screws (7); tightening torque: 1.2 ± 0.1 Nm.
Tighten the Torx T20 screw (4); tightening torque: 3.5 ± 0.1 Nm.
Figure 1: Mounting a blind hollow shaft encoder
8016866/12N8/2019-01-31/de, en, es, fr, it
DFS60S Pro | SICK
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