Siemens 6EP1961-2BA51 SITOP PSE200U 4x3A NEC Class 2 Common Signal Selectivity Module

The Siemens 6EP1961-2BA51 is a SITOP PSE200U selectivity module that splits a 24 V DC/12 A input into four individually protected 3 A NEC Class 2 outputs, with a common signal contact reporting a fault on any channel. Each output trips independently at an adjustable 0.5-3 A threshold set via potentiometer, isolating a faulted branch without taking down the other three.

Certifications & Standards

• CE
• UKCA
• EAC
• CB
• Shipbuilding
• ABS
• DNV
• EPD

Selection Notes

The common signal contact reports one combined fault status for all four channels - pick the 2BA51 variant when the upstream PLC only needs a single alarm input tied to selectivity module health, rather than per-output diagnostics. The 0.5-3 A adjustable threshold lets the same module protect mixed loads from 500 mA sensors up to 3 A field devices without oversizing the whole branch to the highest-current channel. At 97% efficiency and 9 W typical power loss, thermal derating above 60 degC ambient is the main design constraint, not the DIN-rail footprint.

Applications

Deployed downstream of a 24 V DC/12 A SITOP power supply to give each of four load groups - sensors, actuators, remote I/O, HMI - its own current-limited, individually resettable output, so a short on one branch does not pull down the other three or the upstream supply.