SICK MOC3ZA Notice D'instructions page 65

Operating instructions
MOC3ZA
Notes

WARNING
8014608/1DS0/2022-02-16
Subject to change without notice
Commissioning and test notes
➢ Start the motor.
The OUT LED changes its color to  Yellow.
The output circuit switches off.
In case of DC motors, after 2 s the ERR LED flashes  Red with error code 2
(see Fig. 10) and the semiconductor output ERR switches on.
➢ Shut down the motor and leave it to coast down. Only on renewed standstill of the
motor may the OUT LED illuminate  Green again and the output circuit be enabled.
 The standstill time (delay between the voltage dropping below the voltage threshold and
the switching on of the safety-related output relay) can be set using the rotary switch t
 In case or uneven and very slow coasting down, it may be necessary to set the standstill
time t to a larger value to prevent alternating switching on and off of the output relay.
s
To avoid this effect, the voltage threshold U
a renewed safety assessment should be undertaken taking into account the higher
voltage threshold U .
an
 If the enable is only to be provided at very low motor rotational speeds, then set U
the minimum value. Possible alternating switching on and off of the output relay can be
avoided with a higher setting of t
you can also ensure that the safety relay is only switched when the motor is at an
absolute standstill, depending on the coasting down behavior of the motor. This
statement applies in particular for motors that generate a relatively low remanence
voltage.
 In case of slow coasting down, in some circumstances a simultaneity error (see section
8.3 "Error monitoring" on page 67) may occur if the voltage drops below the voltage
threshold U only slowly and not simultaneously on both measurement channels within
an
2.5 s. The measures that can be taken to rectify this problem are as follows:
– Connect the measurement inputs in a single-phase configuration such that all
measurement channels receive as far as possible the same signals (pay attention to
safety assessment).
– Increase the voltage threshold U
 If the time the motor takes to coast down is short, then set t
(0.2 s). This setting is advantageous for shortening machine cycles in automatic
systems.
Ensure people and material are not placed at risk!
Set U and t such that the standstill enable is only provided once a hazard for people and
an s
material due to the rotation of the motor is excluded.
➢ Document the values for U
machine.
➢ Secure the values set for U
cabinet.
© SICK AG • Industrial Safety Systems • Germany • All rights reserved
can also be set a little higher. In this case
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. With a longer delay until the output relay is enabled,
s
.
an
and t determined and set during the commissioning of the
on s
and t against tampering, e.g. by means of a locked control
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Chapter 7
.
s
to
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to the minimum value
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