10.5.2
Automatic reset
Automatic reset
If the slide switch on the device is set to "AUTO", a tripping operation (current-dependent or
temperature-dependent protection) is acknowledged as soon as the recovery time has elapsed
or the temperature measured by the thermistor has dropped below the reclosing value.
WARNING
Automatic restart!
Can result in death, serious injury, or property damage.
The motor switches on again when all the following conditions are met:
• Automatic reset is set
• The cause of the fault message is no longer active
• The overload relay is in automatic mode and an ON command is active
Automatic reset must not be used in applications where there is a risk of serious injury to
persons or substantial damage to property if the motor starts up again unexpectedly.
Make sure that the machine danger zone is kept clear of people at the time of restarting.
Recovery time
The time between tripping and resetting is determined by the recovery time.
The recovery time depends on the tripping method:
1. Recovery time after current-dependent tripping:
On the 3RB24 solid-state overload relay for IO‑Link, the recovery time following current-
dependent tripping is approximately three minutes regardless of the reset mode set. The
recovery time gives the load a chance to cool down.
2. Recovery time following temperature-dependent tripping:
If temperature-dependent tripping takes place through a connected PTC thermistor sensor
circuit, the device can only be reset manually or automatically when the winding
temperature at the installation location of the cold conductor has cooled down to 5 Kelvin
below its response temperature.
3. Recovery time following other faults:
With all other faults, the overload relay is capable of reclosing as soon as the fault has been
removed.
Operation
10.5 Performing a reset
SIRIUS 3RB24 electronic overload relay for IO-Link
Equipment Manual, 07/2022, NEB969165602000/RS-AA/003
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