SIEMENS
5/39
Siemens IK PI · 2015
IO-Link
SIRIUS 3RR24 monitoring relays for mounting onto 3RT2 contactors for IO-Link
Current and active current monitoring
5
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Overview
SIRIUS 3RR2441 and 3RR2442 current monitoring relay
The SIRIUS 3RR24 current monitoring relays for IO-Link are
suitable for the load monitoring of motors or other loads. In three
phases they monitor the rms value of AC currents for over-
shooting or undershooting of set threshold values.
Whereas apparent current monitoring is used above all in con-
nection with the rated torque or in case of overload, the active
current monitoring option, which is also selectable, can be used
to observe and evaluate the load factor over a motor's entire
torque range.
The 3RR24 current monitoring relays for IO-Link can be inte-
grated directly in the feeder by mounting onto the 3RT2 contac-
tor; separate wiring of the main circuit is therefore superfluous.
No separate transformers are required.
For a line-oriented configuration or simultaneous use of an
overload relay, terminal supports for stand-alone installation
are available for separate standard rail mounting.
The SIRIUS 3RR24 current monitoring relays for IO-Link also
offer many other options based upon the monitoring functions of
the conventional SIRIUS 3RR2 monitoring relays:
•
Measured value transmission to a controller, including resolu-
tion and unit, may be parameterizable as to which value is
cyclically transmitted
•
Transmission of alarm flags to a controller
•
Full diagnosis capability by inquiry as to the cause of the fault
in the diagnosis data record
•
Remote parameterization is also possible, in addition to or
instead of local parameterization
•
Rapid parameterization of the same devices by duplication of
the parameterization in the controller
•
Parameter transmission by upload to a controller by IO-Link
call or by parameter server (if IO-Link master from IO-Link
Specification V 1.1 and higher is used)
•
Consistent central data storage in the event of parameter
change locally or via a controller
•
Automatic reparameterizing when devices are exchanged
•
Blocking of local parameterization via IO-Link possible
•
Faults are saved in parameterizable and non-volatile fashion
to prevent an automatic start-up after voltage failure and to
make sure diagnostics data is not lost
•
By integration into the automation level the option exists of
parameterizing the monitoring relay at any time via a display
unit or displaying the measured values in a control room or
locally at the machine/control cabinet.
Even without communication via IO-Link the devices continue to
function fully autonomously:
•
Parameterization can take place locally at the device,
independently of a controller.
•
In the event of failure or before the controller becomes avail-
able the monitoring relays work as long as the control supply
voltage (24 V DC) is present.
•
If the monitoring relays are operated without the controller, the
3RR24 monitoring relays for IO-Link have, thanks to the inte-
grated SIO mode, an additional semiconductor output, which
switches when the adjustable warning threshold is exceeded.
Thanks to the combination of autonomous monitoring relay func-
tion and integrated IO-Link communication, redundant sensors
and/or analog signal converters – which previously took over the
transmission of measured values to a controller, leading to con-
siderable extra cost and wiring outlay – are no longer needed.
Because the output relays are still present, the monitoring relays
increase the functional reliability of the system, since the control-
ler can only fulfill the control tasks if the current measured values
are available, whereas the output relays can also be used for the
disconnection of the system if limit values that cannot be
reached during operation are exceeded.
For further information on the IO-Link communication system,
see page 5/2 onwards.
© Siemens AG 2014