Transformer 18-0-18V 5VA

The Transformer 18-0-18V 5VA is a small centre-tapped step-down transformer with an 18-0-18 V AC secondary and a 5 VA power rating. It provides 18 V AC from each half, or 36 V AC end to end, at up to about 140 mA, making it a good fit for compact ±15 V op-amp supplies, preamplifier boards, measuring instruments and other low-current electronics.

Transformer 18-0-18V 5VA Specifications

• Secondary: 18-0-18 V AC, centre-tapped (18 V + 18 V)
• Full secondary: 36 V AC end to end
• Power rating: 5 VA
• Secondary current: about 140 mA from the full 36 V winding (5 VA ÷ 36 V)
• Primary: AC mains; check the label for the rated input voltage
• Type: step-down transformer with a centre tap

Transformer 18-0-18V 5VA Applications

• Low-current ±15 V supplies with a 78L15 and 79L15
• Op-amp, preamp and instrumentation circuits
• Full-wave rectifiers using two diodes and the centre tap
• Standby and auxiliary supplies inside equipment
• Teaching rectifiers and power supplies in electronics labs

What's in the Box

• 1 × 18-0-18 V 5 VA transformer

Tip: A 5 VA transformer only delivers around 140 mA, so add up your circuit's current before choosing it. Small transformers give a noticeably higher voltage with no load, so rate the filter capacitors at 50 V. The primary connects to mains: insulate it, fit a fuse and work on it only when unplugged.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.