we77WE77Ex-2 115V; WE77Ex-2 115V Switch Amplifier. Key Benefits at a Glance . 2-channel; Control circuit EEx ia IIC; 115 V AC supply voltage; Reversible mode of operation; LeadWE77Ex-1 230V 1-channel Control circuit EEx ia IIC 230 V AC supply voltage Reversible mode of operation Lead breakage (LB) monitoring 1 relay contact output (change-over