Hager ST303 Doorbell Transformer 230V to 8V/12V 8VA 2 Module

Delivers 8 VA of power with dual 8 V and 12 V outputs from a 230 V input, making it a compact solution for doorbell and low-voltage circuits.

Overview

The Hager ST303 is a doorbell transformer that converts 230 V AC mains voltage to either 8 V AC (1 A) or 12 V AC (0.67 A). It is designed for DIN rail mounting (EN 60715) and occupies 2 modules (35 mm) of width. The transformer is thermally protected against short circuits and has a protection class II (double insulated) design. It operates at 50/60 Hz and is suitable for ambient temperatures from -5 to 40 °C.

What stands out

• Dual output voltages: 8 V and 12 V AC for flexible low-voltage supply.
• Compact 2-module DIN rail housing saves space in distribution boards.
• Thermally protected for safe operation under overload conditions.
• Double insulated (class II) for enhanced electrical safety.

Technical details

• Input voltage: 230 V AC
• Output voltage 1: 8 V AC
• Output voltage 2: 12 V AC
• Rated power: 8 VA
• Frequency: 50/60 Hz
• Mounting type: DIN rail (EN 60715)
• Module width: 2 TE (35 mm)
• Degree of protection: IP20
• Protection class: II
• Short-circuit protection: Thermally protected
• Operating temperature range: -5 to 40 °C
• Connection type: Screw terminals
• Standards: EN 61558-2-8
• Max. output current (8V): 1 A
• Max. output current (12V): 0.67 A
• Housing material: Self-extinguishing thermoplastic
• Installation depth: 60 mm

Our verdict

The Hager ST303 is a reliable and compact doorbell transformer, ideal for residential and commercial installations where a dual-voltage low-power supply is needed. Its DIN rail mounting and thermal protection make it a practical choice for electricians.