Hager ST301 Bell Transformer 230V to 8V/12V AC, 0.5A, DIN Rail

Electricians and installers often need a reliable low-voltage supply for doorbells, chimes, and telephone systems in residential and commercial buildings. The Hager ST301 bell transformer converts 230V mains voltage to a selectable 8V or 12V AC output, providing a safe and stable power source for such devices. Its compact DIN rail mounting makes it easy to integrate into distribution boards.

Key specifications

• Input voltage: 230V AC
• Output voltage: 8V or 12V AC (selectable)
• Output current: 0.5 A
• Rated power: 6 VA
• Frequency: 50/60 Hz
• Mounting: DIN rail, 1 module width
• Protection class: IP20
• Short-circuit protection: thermal
• Overload protection: thermal
• Transformer type: safety isolating transformer
• Connection: screw terminals
• Operating temperature: -5 to +40 °C
• Housing material: thermoplastic
• Colour: light grey

Why choose it

The ST301 provides a safe, isolated low-voltage supply, protecting both the connected devices and users. Its selectable output voltage offers flexibility for different bell systems, and the thermal protection ensures long-term reliability.

Ideal use cases

• Powering doorbells and chimes in homes and offices
• Supplying low voltage to telephone systems
• Integration into electrical distribution panels for building installations

Good to know

The transformer is designed for DIN rail mounting and occupies only one module width, saving space in the distribution board. It complies with EN 61558-2-8 for safety isolating transformers.