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Isolation Transformer

Product Range

Models in This Range

We get a lot of questions about this range, and the pattern is always the same: “My amplifier hums and I can’t find the ground loop.” “The lab equipment glitches whenever the lift starts.” “The client’s spec says the X-ray room needs an isolation transformer — can you build it?” Yes, yes and yes. An isolation transformer does not change your voltage — that is the whole point. It separates the input from the output electrically, so ground loops, common-mode noise and transients from the mains cannot reach the equipment it feeds.

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Overview

What This Series Does

Isolation transformers supply the same voltage on the output while separating it completely from the input, protecting sensitive equipment from ground loops, noise and faults.

Used in audio studios, hospitals, laboratories, data racks and industrial cabinets in 120V and 240V markets worldwide.

Specifications

Key Specifications

Voltage 110V / 120V / 220V / 230V / 240V in-out (1:1)
Capacity 500VA – 10KVA
Frequency 50Hz / 60Hz compatible
Isolation Fully separate windings + electrostatic shield
1:1240V120V50/60HzScreened

Guide

Welcome to our isolation transformer range. If you are reading this, chances are you have equipment that misbehaves on the mains — hum in the audio, glitches in the lab, or a medical spec that demands isolation. An isolation transformer is the piece that sits between the wall and your equipment, and its only job is to make the connection cleaner and safer. This page walks you through what we make and how to pick the right one.

What we make in this range

Our isolation transformers come in five models, and they share the same core: fully separate primary and secondary windings on a silicon steel core, with an electrostatic shield between them. That shield is what blocks common-mode noise, and the separation is what breaks ground loops. Every unit is wound with copper, varnish-dipped, and tested before it goes into a carton.

  • ISO-240 – 240V to 240V isolation for the UK, the Middle East, Africa and Southeast Asia. The workhorse for studios, labs and industrial cabinets.
  • ISO-120 – 120V to 120V isolation for North America, Japan and 120V markets. Same isolation job on the US-standard mains.
  • ISO-115 Audio – the audio-grade model with a quieter core option, built to kill ground-loop hum in hi-fi and studio systems.
  • ISO-MED – reinforced insulation and low leakage design for hospitals, clinics, dental and laboratory equipment.
  • ISO-500 – the compact 500VA entry size for test benches, single audio components and small lab instruments.

Why buyers come to us direct

Most of our isolation transformer customers are not buying one unit. They are outfitting a studio, a clinic, a workshop, or stocking for resale. That changes what they care about: a transformer that will not hum or overheat, a supplier who answers within a day, and a price that leaves room to resell. That is the whole reason we sell factory direct — no trading company in the middle, and our MOQ is just 10 pieces.

Voltage and capacity we cover

Standard models we build weekly: 110V to 110V, 120V to 120V, 220V to 220V, 230V to 230V and 240V to 240V, from 500VA to 10KVA. Beyond that, tell us your input, output and capacity, and we will wind it to match. Custom builds can add medical-grade insulation, extra shielding, terminal blocks instead of sockets, or OEM branding.

Picking the right size

The short answer: add up the wattage of everything that runs at the same time and add 30% headroom. A 500VA unit comfortably feeds about 350W, which covers a turntable, a DAC and a preamp. A 1000VA unit covers a small stereo system, 2000VA covers a full home theater or a lab bench, and 5000VA covers industrial or medical loads. If you are not sure, send us your load list and we will confirm a model within 24 hours.

Ready to look at specific models? Browse the ISO-240 240V isolation transformer, the ISO-115 audio isolation transformer, or the ISO-MED medical isolation transformer for a closer look at specs and photos.

What Is an Isolation Transformer?

An isolation transformer is a 1:1 transformer whose primary and secondary windings are electrically separate. The voltage does not change — that is the design. What changes is the connection: there is no conductive path between the input and the output. That separation is what blocks ground loops, common-mode noise, DC offset and transients from reaching your equipment, and it is what protects people from shock when a single fault occurs on the equipment side.

How It Works

How Does It Work?

Inside the unit, the primary winding is energized by your mains and creates a magnetic field in the core. The secondary winding, wrapped around the same core, picks up that field and delivers the same voltage to the output. Because the two windings share only a magnetic path, not an electrical one, power crosses the barrier without a conductor between input and output. An electrostatic shield between the windings bleeds common-mode noise to earth, which is why our units are quieter than a plain transformer.

Series

Series We Make

ISO-240 / ISO-120

Standard 1:1 isolation in 240V and 120V markets, 500VA to 10KVA.

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ISO-115 Audio

Audio-grade isolation with quiet core options, for hi-fi and studio.

ISO-MED Medical

Reinforced insulation and low leakage for hospitals and clinics.

Custom Build

Any voltage, 500VA to 10KVA, extra shielding and OEM branding.

Applications

Applications & Benefits

  • Audio and hi-fi systems with persistent ground-loop hum
  • Recording studios, home studios and live sound racks
  • Hospital, clinic, dental and laboratory equipment
  • IT racks, data centres and sensitive electronics
  • CNC machines and PLC panels in industrial cabinets
Need help choosing?

Tell us what equipment you are feeding and where it runs, and we will confirm the right isolation transformer within 24 hours.

Request a Quote

FAQ

Questions Customers Ask Us

What is the warranty?
12 months from delivery on every unit, replacement-first.

What is the minimum order quantity?
From 10 pcs. OEM branding available from this volume.

Can you customize voltage and capacity?
Yes — any voltage combination, capacity and enclosure is built to order.

What is the typical lead time?
15–25 days production plus shipping to your country.

Guides & Articles

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