Aerco and Lucy Switchgear, part of the W. Lucy Group, have completed a new joint development programme to design a bespoke solenoid system to be used in a new generation of secondary switchgear products. Engineers at Lucy Switchgear decided to specify solenoids for a new generation of Direct Acting Trip mechanisms that provide earth fault and over current protection for new secondary switchgear circuit breakers.
They contacted the Aerco DESIGNSUPPORT team when it was evident that there was no commercially available, standard solenoid that met the demanding specification. Although Aerco stocks and supplies a wide range of standard solenoids from Mechetronics and BLP it was confirmed that there was not a standard solenoid that would meet this application in terms of coil rating and construction.
The Aerco DESIGNSUPPORT team worked with the design departments of both Mechetronics and Lucy Switchgear to provide a complete new assembly with a back plate and three solenoids, one each for the red and blue phases and one for earth fault. Standard Mechetronics frame solenoids type SD137 were used but these were fitted with special coil windings. A special calibrated plunger thrust rod was also fitted and the normal residual springs replaced with specially designed return springs.
The mechanism is manufactured by Mechetronics and Aerco holds stock of the complete assembly with a two-day delivery to Lucy Switchgear in Oxford from where it is shipped to Dubai for final assembly.