Operating instructions Chapter 5
MOC3ZA
8014608/YT32/2016-03-15 © SICK AG • Industrial Safety Systems • Germany • All rights reserved 59
Subject to change without notice
Electrical installation
en
5 Electrical installation
Switch the power supply off!
The machine/system could unintentionally start up while you are connecting the devices.
⋅ Ensure that the entire machine/system is disconnected during the electrical
installation.
• Please pay attention to the notes and regulations in chapter 4 “Mounting” on page 57.
• The Standstill Monitor MOC3ZA is to be wired as per the examples in chapter 6
“Application examples and connection diagrams” on page 61. DC motors are connected
in the same way as single-phase AC motors.
• The MOC3ZA corresponds to class B according to EN 55 011.
• On laying out the control cabinet it is in general to be ensured that physical separation
is maintained between power components (electrical drives, valve controllers, power
regeneration devices, etc.) and control components (PLC, auxiliary relays, etc.).
• To meet the requirements of the relevant product standards (e.g. IEC 61 496-1), the
external voltage supply for the devices must be able to bridge a brief mains failure of
20 ms. Suitable power supplies are available as accessories from SICK.
• For the voltage supply to DC devices (A1/A2) and to the terminals A3/A4, the
regulations for low voltage with safe separation as per EN 60 664 and EN 50 178
(Electronic equipment for use in power installations) must be met.
• The supply voltage (A1/A2) must be connected as per the voltage information on the
type label and limited by means of an external fuse.
• On the usage of the non-safety semiconductor application diagnostics outputs a supply
voltage must be connected to A3/A4 and protected by means of an external fuse.
• If the outputs are connected to a capacitive or inductive load, then the load connected
must have an adequate suppressor for protection against overloading of the switching
contacts.
• To protect the safety outputs, it is recommended to also protect the safety contacts. In
order to increase the service time, external loads must be equipped with e.g. varistors
or RC circuits. Please note that the response times can be increased depending on the
type of the suppressor. On this topic, see also chapter 9 “Technical specifications” on
page 72.
Connection of the measurement inputs L1/L2/L3
⋅ Connect the measurement inputs L1/L2/L3 directly to the windings on the motor to be
monitored for standstill (that is not e.g. via transformers) so that continuous monitoring
of the windings and the cable for wire break is ensured.
⋅ Do not disconnect the motor windings from the measurement input cables by means of
motor contactors or the like, as otherwise a wire break error will be triggered and
standstill monitoring will not be possible.
⋅ Prevent the coupling of interference onto the measurement input cables, as otherwise
in certain circumstance the MOC3ZA may not be able to detect standstill.
⋅ Lay the measurement input cables separately or screen if possible. The screen can be
connected to the motor.
WARNING
Notes