What it is and what it does
The Siemens 3VA9113-0RL21 is a SENTRON residual current protection module — type B and B+ — that mounts load-side on a 3VA1 molded case circuit breaker. It's the accessory that turns a standard 3VA1 breaker into an RCD-protected combination unit for systems where adjustable ground-fault detection is needed. Rated at 160 A continuous on AC, this module covers the main feeder or large subfeed. The residual current trip threshold is field-selectable across eight settings from 0.03 A up to 5 A, and the time delay can be dialed in from 0 to 10.0 s in ten steps. Type B and B+ detection means it catches AC sinusoidal, pulsating DC, smooth DC, and high-frequency residual currents — the kind you get from VFDs, UPS systems, and EV chargers. That's the main reason you spec this over a type A module: without it, a drive's switching harmonics can blind a standard RCD.
Where it fits and how it mounts
This module is designed as a bolt-on accessory for the 3VA1 breaker family, not a standalone DIN-rail device. It attaches to the load side of the breaker via busbar connection and is secured with screw fixing. Infeed can enter from the top or bottom, which gives some layout flexibility inside the panel. Physical footprint: 70 mm deep, 101.6 mm wide, 100 mm tall. That width matches the 3-pole 3VA1 breaker it pairs with, so the assembly keeps a clean, uniform front. The front face carries IP40 protection — fine for a dry indoor panel, but it's not sealed against washdown or dust ingress. Max power dissipation is 7.6 W. That's modest, but in a densely packed panel with multiple breakers running near rated load, it's worth checking the thermal rise — especially if the enclosure is small and unventilated.
Adjustability and diagnostics
The module supports selectable RCD or monitoring mode and selectable tripping characteristic. That means you can use it purely as a monitor/alarm device without tripping the breaker, or set the trip curve to match the downstream load type. A pre-alarm indication triggers at 30% of the set residual current value — useful for predictive maintenance before a nuisance trip hits. An electrical trip indicator is built in, but there's no communication interface for remote tripping or remote monitoring. If you need to tie ground-fault events into a PLC or SCADA, you'll need an external add-on or a different accessory variant. The module is sealable — important for utility or metering applications where tamper prevention is required after commissioning.
Lifecycle and sourcing reality
Because it's a dedicated accessory for the 3VA1 platform, there's no direct second-source drop-in. The module is specific to that breaker family's mechanical interface and busbar system. If your BOM calls for this order code, the fit is confirmed — no adapter or rewiring needed on a 3VA1 panel.