BRT 21, BRT 22, BRT 23 SITAC AC Switches Without Zero Voltage Switch are AC switch with zero-voltage detector. They are electrically insulated between input and output circuit, microcomputer-compatible by very low trigger current.
The BRT 21, BRT 22 and BRT 23 are Siemens SITAC® AC switches featuring zero‑voltage detection, electrical isolation between input and output, and low trigger current. They are UL‑tested (file no. E 52744) and available with options such as VDE‑approved construction and surface‑mount pins.
Key electrical ratings include a maximum power dissipation of 630 mW (input) and 600 mW (output), continuous forward current of 20 mA, repetitive peak off‑state voltage up to 800 V, and RMS on‑state current of 300 mA. Detailed trigger currents and thermal characteristics are provided for each model variant.
| Maximum Power Dissipation (Input) | 630 mW |
|---|---|
| Maximum Power Dissipation (Output) | 600 mW |
| Continuous Forward Current | 20 mA |
| Repetitive Peak Off‑State Voltage | 400 V / 600 V / 800 V |
| RMS On‑State Current | 300 mA |
| Trigger Current (Type H) | ≈4 mA |
The switches can dissipate up to 630 mW in the input circuit and 600 mW in the output circuit.
The continuous forward current is 20 mA.
The trigger current for type H switches is about 4 mA.