WIRING DIAGRAMS
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Instructions for resetting the circuit-breaker after tripping
2. Electrical resetting under the operator's responsibility To be wired (by the customer): contact SO1, SO2, contact SY/1 and the auxiliary relay KO (only for MOD). Opening of the circuit-breaker is allowed by means of the contact S02. Such contact shall be protected to avoid unwanted activation and can be used only if the information received by the operator make it possible to exclude tripping due to a short-circuit, or if the causes of the short-circuit have been removed. 3. Electrical resetting always allowed To be wired (by the customer): contact SO1, SO2, contact SY/1 and the auxiliary relay KO (only for MOD). Opening is always allowed by means of contact S02. NB: If the magnetic, thermal magnetic or electronic trip unit is present, it is necessary to find the causes which led to the circuit-breaker being in the tripped position so as to prevent reclosing under short-circuit conditions. In all cases, manual reset- ting is always allowed.
Selection of the type of circuit-breaker resetting depends on design requirements and on service conditions. Resetting can take place following tripping of the following releases: • overcurrent;
• undervoltage; • shunt opening.
The following three possibilities are suggested (see diagrams in the following page): 1. Only manual resetting To be wired (by the customer): contact SO1, contact SY/1 and the auxiliary relay KO (only for MOD). Opening is prevented until the circuit-breaker is in the tripped position. To reset the circuit-breaker it is necessary to activate the special lever on the front of the motor until the circuit-breaker goes into the open position.
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