DANGER - Blemo

Thermal protection
Soft starter thermal protection
The thermal protection is provided by the temperature sensor installed on the heatsink.
Motor thermal protection
Standard IEC 60947-4-2 defines the protection classes giving the starting capacities of the motor (warm or cold start) without thermal faults.
Different protection classes are given for a COLD state (corresponding to a stabilized motor thermal state, switched off) and for a WARM
state (corresponding to a stabilized motor thermal state, at nominal power).
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• The soft starter is factory set to protection class 10.
• This protection class can be modified using tHP parameter in SEt menu.
• The motor thermal state is stored in memory. No estimate of motor cooling is calculated while power of the control part is off.
• An overload alarm is activated if motor thermal state exceeds 110%.
• A thermal trip OLF stops the motor if motor thermal state exceeds 125%.
• If the thermal protection has not been disabled, the thermal trip can be indicated by a relay depending on output assignment.
• After the motor has stopped or the soft starter has been switched off, the thermal state is saved. At next start or switch on, the thermal
protection value is restored.
• If a special motor is used (explosion proof, submersible, etc.), the thermal protection should be provided by PTC probes.
RISK OF DAMAGE TO THE MOTOR
See Motor thermal protection with PTC probes, page 25.
CAUTION
The use of external overload protection is required under the following conditions:
• Running multiple motors
• Running motors rated at less than 40% of the nominal soft starter current
• Using motor switching
• Using special motor (explosion proof, submersible, etc...)
Failure to follow these instructions can result in equipment damage.