EN / ACS800-31/U31 Hardware Manual - Simark Controls

482) Circuit breakers which have been tested by ABB with the ACS800 can be used. Fuses must be usedwith other circuit breakers. Contact your local ABB representative for approved breaker types andsupply network characteristics.The protective characteristics of circuit breakers depend on the type, construction and settings of thebreakers. There are also limitations pertaining to the short-circuit capacity of the supply network.WARNING! Due to the inherent operating principle and construction of circuit breakers,independent of the manufacturer, hot ionized gases may escape from the breakerenclosure in case of a short-circuit. To ensure safe use, special attention must be paid tothe installation and placement of the breakers. Follow the manufacturer’s instructions.Note: Circuit breakers without fuses are not recommended in the USA.3) Size the fuses according to local safety regulations, appropriate input voltage and the rated current ofthe drive (see Technical data).4) ACS800-07/U7 units and ACS800-02/U2 units with enclosure extension are equipped with standard gG(US: T/L) or optional aR fuses listed in Technical data. The fuses restrict drive damage and preventdamage to adjoining equipment in case of a short-circuit inside the drive.Check that the operating time of the fuse is below 0.5 seconds. The operating time depends on thefuse type (gG or aR), supply network impedance and the cross-sectional area, material and length ofthe supply cable. In case the 0.5 seconds operating time is exceeded with gG fuses (US: CC/T/L),ultrarapid (aR) fuses will in most cases reduce the operating time to an acceptable level. The US fusesmust be of the “non-time delay” type.For fuse ratings, see Technical data.Planning the electrical installation