Transformer Buying Guides
Step down, step up and control transformer sizing guides. Pick the right VA rating and buy factory direct from China.
Frequently asked questions about transformer buying guides
How do I choose the right transformer size?
Add up the wattage of everything you plan to run, then add 25% headroom. Motors and compressors need more - size them at three to five times running wattage to survive startup surge. When in doubt, go one size up.
What is the difference between a step down and a step up transformer?
A step down transformer drops voltage, for example 220V to 110V for US appliances. A step up transformer raises it, for example 110V to 220V. Both work on the same principle - only the winding ratio changes.
How much does a step down transformer cost?
Small 100W to 500W units start around fifteen to thirty dollars, and a 2000VA unit for a whole room costs more. Buying factory direct removes the distributor margin, which is usually where the price doubles.
What is your MOQ and lead time?
Our MOQ is 10 pieces for standard models and lead time is 15 to 25 days depending on order size and winding specification. We ship FOB Ningbo or Shanghai, and every unit is tested before it leaves the floor.
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