2005-09-15 - The first eVM1 circuit-breaker was installed on 4th August 2005 at the primary substation of Tremosine, belonging to the ASM Brescia S.p.A. electricity utility. The primary substation of Tremosine distributes electric power in the western top area of Lake Garda and the eVM1 supplies one of the overhead outgoing feeder lines.
eVM1 are integrated medium voltage circuit-breakers with highly innovative functions. They are built with a bistable drive with permanent magnets and incorporate the current measurement sensors and protection and control electronics.
“Integration of these parts in a single product considerably reduces cabling and accelerates construction of switchgear” explains Carlo Cereda, Product Manager for medium voltage apparatus. “The reduced number of moving parts – a typical feature of circuit-breakers with magnetic drive – and the electrical interfacing connections with the switchgear have, furthermore, the merit of increasing overall reliability of the system”.
Compared with a conventional medium voltage circuit-breaker, the integrated eVM1 circuit-breaker offers considerable advantages both at the installation stage and during service, such as factory-testing of all the functions, simplification of ordering procedures, more rapid installation and putting into service of the substation, improvement of service safety and reliability, drastic reduction in cabling, monitoring of all trip functions, as well as a wide range of auxiliary power supply in direct and alternating current.
“The ABB offer for OEMs is enlarged with the eVM1 circuit-breakers. Using such an innovative product provides numerous benefits and simplifies the work of switchgear experts” states Antonio Marinoni, Product Marketing Manager of medium voltage apparatus. “Furthermore, the eVM1 circuit-breaker is a highly advantageous solution in the case of retrofitting operations, just because a single product takes the place of the circuit-breaker, sensors and protections”.
With a standard solution, the eVM1 circuit-breakers realise the concept of an automatic medium voltage circuit-breaker for primary distribution. A user interface fitted with an ammeter, which can be applied onto the auxiliary circuit compartment door of the switchgear, allows control of the device.
The protection functions are in accordance with IEC 60255-3 and IEC 60255-8 Standards: overcurrent and earth fault as standard and, in addition to these, in the full-option version: motor start-up protection, number of start-ups, locked rotor, thermal overload, and unbalanced load.
The eVM1 circuit-breakers have recently completed the validation tests, including the special tests for verifying sturdiness of the electronics in environments with high electromagnetic interference, and fully comply with the specifications for electromagnetic compatibility.