Siemens 6EP4448-7FB00-3CX0 SITOP SEL1200 48 V 10 A Selectivity Module. Siemens 6EP4448-7FB00-3CX0 Power Supply Accessory - SITOP SEL1200 48 V 10 A selectivity module 4-channel with switching characteristic input: 48 V DC/40 A output: 48 V DC/4x 10 A threshold value adjustable 1-10 A with monitoring interface. Input: 48 V DC/40 A, Output: 48 V DC/4x 10 A threshold value adjustable 1-10 A with monitoring interface.