256-byte I/O map, 20 mm wide — what fits in the ET 200SP slot
The Siemens 6ES7134-6PA20-0BD0 is an AI Energy Meter module for the SIMATIC ET 200SP distributed I/O system. It occupies one 20 mm-wide BaseUnit slot (BU type D0) and draws 256 input bytes and 12 output bytes from the backplane — that's the full I/O map for a three-phase power measurement channel with voltage, current, and frequency capture. Rated for AC 100–277 V line-to-neutral, it measures sinusoidal or distorted waveforms via a sigma-delta ADC. The 0.6 W typical power loss stays cool in a densely packed ET 200SP station — no derating needed for adjacent modules.
The 58 mm depth and 20 mm width match the standard ET 200SP footprint — snaps onto a BU type D0 BaseUnit (order separately). Mounting position is any orientation, so it fits horizontal or vertical DIN-rail layouts without clearance concerns. Unshielded cable runs up to 200 m are allowed for the voltage inputs — the sigma-delta measurement principle rejects common-mode noise well enough that a shielded run isn't mandatory in a clean panel. For noisy environments (VFD cabinets, welding lines), shielded twisted-pair is still the safer bet. Zero-point suppression is parameterizable from 2 to 250 mA (default 50 mA) — useful for ignoring transformer magnetising current or light-load leakage on a motor feeder. The hardware interrupt monitors up to 16 freely selectable process values for over/undershoot, so the PLC can trip on a current spike without polling the I/O map.
Diagnostic and alarm coverage
Diagnostic alarm, limit value alarm, and channel diagnostics (red Fn LED) are all present. The green DIAG LED reports module status; the green channel LED shows per-channel activity. I&M data (I&M0 to I&M3) is supported for asset tracking in TIA Portal. Isolation tested at 2300 V AC for 1 minute (type test) between the secondary side and the backplane — sufficient for 480 V line-to-line systems. Surge strength is 10 A for 1 minute.