Step Down Transformer 240V to 120V | STU Series
STU step down transformer for 240V to 120V. Automatic, copper wound, batch tested. Also steps 120V up to 240V. Overview This STU series unit is configured…
- Factory-direct pricing, no middleman markup
- Custom voltage, capacity and branding (OEM)
- MOQ from 10 pcs, production 15–25 days
- 12-month warranty with reliable support
STU step down transformer for 240V to 120V. Automatic, copper wound, batch tested. Also steps 120V up to 240V.
Overview
This STU series unit is configured for the step down direction: a 240V supply in, 120V out, for appliances and equipment built for the lower voltage. It is the same automatic bidirectional transformer we ship worldwide – wire it for 240V input and it delivers clean 120V to your equipment, and the same unit steps 120V up to 240V if you ever need the reverse. Copper-wound and 100% tested in our own factory in Yueqing, China.
The typical buyer is running 120V gear on a 240V grid: US-spec appliances, power tools, home theater, kitchen equipment moved across regions. Importers and resellers stock the STU series because one automatic unit serves both directions and every socket standard, which keeps their inventory simple and their customers happy.
Key Specifications
| Parameter | Value |
|---|---|
| Input Voltage | 110V–120V ↔ 220V–240V (automatic) |
| Output Voltage | 110V–120V ↔ 220V–240V (automatic) |
| Capacity Range | 1000VA – 10000VA (STU series) |
| Frequency | 50Hz / 60Hz |
| Protection | Fuse / MCB protection |
| Output Sockets | Optional (US / EU / UK styles) |
| Winding | Copper, varnish-impregnated |
| Warranty | 12 months |
Features
- Automatic voltage selection – no manual tap, no wiring guesswork.
- True bidirectional conversion – steps 240V down to 120V and 120V up to 240V.
- Real copper windings – cooler running, steadier output under load.
- 50/60Hz rated – works on either mains frequency.
- Batch tested – every unit load-tested and recorded before shipping.
- OEM ready – your brand, your packaging, custom sockets.
Typical Applications
- US-spec 120V appliances running on a 240V grid
- Power tools and workshop gear imported from 120V markets
- Kitchen and home theater equipment moved across regions
- Import and resale stock for voltage conversion
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More from This Range
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STU-3000 Step Up & Step Down Transformer3000W heavy-duty bidirectional converter.
DT-1000VA Step Up & Step Down Transformer1000VA automatic bidirectional unit.
Frequently Asked Questions
Can the STU series step 240V down to 120V automatically?
Yes. The STU series selects the input voltage automatically and converts between 110-120V and 220-240V in both directions. Feed it 240V and it outputs 120V for your equipment.
What size transformer do I need for my 120V appliances?
Add the wattage of everything you run, add 30% margin, and double it for motor loads. A household with a few appliances fits on 3000VA; workshops want 5000VA or more.
What sockets does the output have?
US, EU or UK sockets are available, matched to your appliances. We also supply units with bare terminals for permanent wiring.
Can I order STU transformers with my own brand?
Yes, OEM branding from MOQ 10 pcs per model, with custom sockets, packaging and your label on the case.
What is the MOQ and lead time?
MOQ is 10 pcs per model, production takes 15-25 days, FOB Ningbo or Shanghai, with CE / RoHS documents.