When and Why is a Frequency Converter Necessary


Step Down Transformer Typically this situation arises when a United States manufactured vessel travels outside of the United States. The US electrical system and simple electrical devices operating in that system are designed to use 120 volts alternating current running at 60 hertz (HZ). When you leave the US, electrical systems are usually based on 120 or 220/240 Vac running at 50 Hz. Any electrical device placed in service outside of a system it was designed to be run in will suffer damage and eventually fail. In extreme cases, an electrical fire may result!

Some people just rely on a step down transformer as shown in the picture on the left. They are inexpensive, but do not do the job correctly. Typically they step the voltage down from 220/240 Vac that is running at 50 Hz to 120 Vac that will still be running at 50 HZ. However, if the utility power being supplied is 220/240 Vac running at 60 Hz, then a step down transformer will be a proper solution.

Frequency Converter Pictured at left is a single phase solid State frequency converter. Not only does it change 50 to 60 or 60 to 50 Hz, but it is also a step down transformer. This particular unit accepts input voltages of 120 or 220 vac and frequencies in the range of 45 to 65 Hz. The output voltage will be 120 or 220 Vac and the frequency is switch selectable to 50 or 60 HZ.

Line isolation, harmonic cancellation, power factor correction, phase conversion, emi filtration, and a pure sine wave output form are just a few of the other feature this unit offers. The unit weighs 150 pounds and its dimensions are 21.5" L x 7.5" W x 19.5" H.

The only apparent factor why some may choose a step down transformer over a proper frequency converter is cost. A step down transformer may be purchased for under $100usd, but a proper frequency converter is expensive to manufacturer. Aside from the smallest units (1.0, 1.25 Kva via UPS) all units need to be delivered via freight at an additional charge. However, when one considers the damage that will (not if) and when (sooner, not later) be done to electrical devices being run on defective power, the payback is apparent and quickly recouped. Consider what your Inverter/Charge, Microwave, Batteries, Computer and other 120vac devices cost and functionality provided and it will not take long to realize the considerable expense, inconvenience (at best), and detriment to safety that will be eliminated. Contact ZRD to size a proper solution to fit your needs.

Prices Subject to Change:

Single Phase units:
1.00 Kva - List $3,700, Retail $2,775
1.25 Kva - List $4,525, Retail $3,375
1.50 Kva - List $5,075, Retail $3,775
3.00 Kva - List $6,000, Retail $4,475
4.00 Kva - List $9,000, Retail $6,775

Also Available:
5, 8, 10, 12 Kva units

Multi-Phase Units Available:
Single Phase to 3 Phase 10Kva to 50Kva
3 Phase to Single Phase 10Kva to 50Kva
3 Phase to 3 Phase 10Kva to 320Kva

↑ Recommend ZRD