8 NAMUR channels, SIL 3, end-of-life
The Siemens 6ES7326-1RF00-0AB0 is a fail-safe digital input module carrying 8 NAMUR-compliant inputs (DIN 19234) that can be configured as 8 one-channel or 4 two-channel paths for redundant safety wiring. Single-channel wiring achieves SIL 2 and Category 4; two-channel wiring reaches SIL 3 and Performance Level e.
Ex(i) approval and sensor power
The module is approved for intrinsically safe Ex(i) applications, with a NAMUR sensor supply of 8.2 V DC, a no-load voltage ceiling of 10 V, and a short-circuit current limit of 13.9 mA — the typical NAMUR characteristic that lets the module detect wire breaks and short circuits as diagnostic events. Maximum permissible external capacitance is 3 µF and inductance 80 mH, so the wiring distance to an Ex(i) zone sensor is bounded by the cable's own L/R and C — shielded runs up to 200 m, unshielded 100 m, per the module's spec.
Panel fit and backplane loading
Occupies a single slot (80 × 125 × 120 mm, 482 g) and draws 90 mA from the 5 V DC backplane bus plus up to 160 mA from the load supply L+ — a combined 4.5 W typical dissipation. Requires a 40-pin front connector (not included) for field wiring; the module reports diagnostic alarms and a group-error SF LED, and the backplane isolation is tested at 500 V DC between channels and to the bus.