The operating element of the 3A20 Series is based on the well proven 6R heavy duty attracted armature control relay. The DC version of this relay is inherently immune to AC voltages & the addition of an AC filter circuit & copper shield over the core of the receive relay greatly enhances this attribute while maintaining high sensitivity to DC voltages.
A mechanical flag indicator is provided on both the send & receive elements which drops on pick up. Manual & self reset version available.
The 3A201 send element is used to apply a DC control voltage to the pilot wire which will be detected by the 3A200 receive element & the auxiliary contacts picked up.
The 3A202 version combines a 3A201 send & a 3A200 receive element in a single case (2KV & 5KV versions only).
The 3A203 version combines 2x 3A200 receive elements in a single case (2KV & 5KV versions only).
Alstom: MVAW11, MVAW21
Reyrolle: Type GF, B22