Premium 3AG Slow-Blow Glass Fuses (1A to 3A) for Valve Amps

Designed for high-voltage tube circuits running on Australian 230V / 240V mains power, our 3AG slow-blow (time-delay) glass fuses deliver essential electrical protection for mains transformers, HT lines, and power supplies.

When you flip the standby switch on a valve amp, filter caps charge instantly and heater filaments draw a heavy initial current spike. Standard fast-blow fuses will often nuisance-trip. These 3AG time-delay fuses feature a built-in surge buffer to safely ride through start-up inrush current while remaining fast to disconnect during a true transformer short or power tube failure.

Specifications

AU Voltage Fuse Sizing Guide (230V–240V)

Note on Voltage: In Australia (230V–240V), a valve amp draws roughly half the mains current of the same amp running on US 120V power. Always match your fuse rating to the 230V/240V specification on your amp's rear panel!

• 1 Amp & 1.5 Amp:

  • Mains Fuses: Ideal for 15W to 50W valve heads and combo amps operating on 240V mains.

  • Internal Protection: Commonly used for High Tension (HT) rail protection and DC power supplies across higher-wattage heads.

• 2 Amp & 2.5 Amp:

  • Mains Fuses: Typical mains fuse rating for high-power 100W–120W tube amplifiers running on Australian voltage.

  • Filament Lines: Used for dedicated 6.3V heater supply circuit lines.

• 3 Amp:

  • Mains Fuses: Suitable for ultra-high-power valve rigs (e.g., 200W+ bass heads like SVTs or high-power multi-transformer setups) or heavy-duty bench power supplies.

Tech Tip: Always check the amp's back panel or service manual for the exact T (Time-Delay) amperage specified for 230V/240V input. Never replace a slow-blow (T) fuse with a fast-blow (F) fuse, and never up-size the fuse rating to bypass a recurring fault.

Why Source Your Valve Amp Fuses From Us?

1. Inrush Current Buffer: Specifically built to withstand 240V filter-cap charging surges and high heater load spikes on power-up.

2. 250V Safety Rated: Fully rated for high-voltage AC mains and high HT DC lines inside tube chassis.

3. Exact Standard Fit: Standard 6.3mm x 32mm dimensions fit standard chassis-mount, inline, and panel fuse holders.

4. Fast Local AU Shipping: Get your amp back on stage without waiting weeks for overseas freight.