HAGER ST305 Doorbell Transformer 230V to 8/12V AC 8VA DIN Rail

Installers and electricians working on doorbell and low-voltage signaling systems will appreciate the HAGER ST305 transformer. It steps down 230V AC mains voltage to a safe 8V or 12V AC, delivering 8VA of power for reliable operation of bells, chimes, and buzzers. The unit mounts on a standard DIN rail (EN 60715) and occupies just 2 modules (36mm) in a distribution board.

Key specifications

• Primary voltage: 230V AC
• Secondary voltage: 8V AC / 12V AC
• Rated power: 8 VA
• Frequency: 50/60 Hz
• Mounting: DIN rail (EN 60715), 2 TE width
• Connection: screw terminals, max cable cross-section 4 mm²
• Short-circuit proof and thermally protected
• Operating temperature: -5°C to +40°C
• Housing: self-extinguishing thermoplastic
• Insulation class: E

Why choose it

The ST305 is a safety bell transformer built to EN 61558-2-8, ensuring safe isolation between primary and secondary circuits. Its compact DIN rail design simplifies installation in modern electrical panels, and the dual voltage output (8V/12V) offers flexibility for different doorbell requirements.

Ideal use cases

• Powering residential doorbells and chimes
• Low-voltage signaling in commercial buildings
• Integration into distribution boards where DIN rail mounting is required

Good to know

The transformer is short-circuit proof and includes thermal overload protection, enhancing safety and longevity. Screw terminals accommodate conductors up to 4 mm², ensuring secure connections.