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10 years, 9 months ago.
Transformer alternative?
Hi, I want to convert AC to DC for some application. I need an alternative to the transformer as the moisture and other environmental conditions will not allow the transformer to work efficiently. So is there any alternative?
4 Answers
10 years, 9 months ago.
A transformer converts AC to AC, a rectifier converts AC to DC. If what you need is a power supply to connect your circuit to mains you have the choice of a classical transformer followed by a rectifier, buffer capacitor and often a voltage regulator (linear or switched), or a switched mode power supply which uses a much higher frequency and hence smaller transformers and capacitors and also takes care of voltage regulation. The switched mode supplies are usually more efficient because they have less iron and copper losses than the classical transformer. A linear voltage regulator is also very inefficient. I do not see the effect of environmental conditions on efficiency. A classical transformer can be completely sealed and is immune to moisture. In my opinion a switched mode power supply with its complex high voltage electronics is much more vulnarable to moisture than a simple transformer, rectifier, capacitor design that only has two contacts that are connected to mains and can easily be isolated.
10 years, 9 months ago.
What is the available AC voltage and what DC voltage do you need?
I guess something like this? http://www.maplin.co.uk/weatherproof-power-supply-dc-12v-3.5a-228966 However, I'm going to put a very strong warning against doing mains wiring unless you're qualified or have a very good understanding of the necessary safety precautions (I definitely don't include myself in that bracket). No project is worth dying for!
posted by 02 Jul 2013
10 years, 9 months ago.
what voltages and how much current do you need ????
Also .. What is avalable?
MIMA !!
More Info More Ansewrs
10 years, 9 months ago.
As already stated above, environmental conditions have no impact on efficiency. The most direct approach is with a classic magnetic transformer with a rectifier and a switcher. It is simpler to design, usually more reliable, but significantly heavier and slightly less efficient than the switch mode type described by Ad van der Weiden. That type is quite common today in many appliances and laptops, because it is less expensive, lighter and it avoids the dreaded power factor issues common to transformer with a rectifier design. But the reliability is, just because of its complexity, lower. In both cases the supply needs to be designed for its working environment. This means operating temperature range, which is primarily the electrical design issue. Vibration, humidity, altitude, etc. are addressed by the mechanical design. There are many power supplies available off-the-shelf, but if you have specific environmental requirements you may have to design your own or subcontract it.
i want alternative to tranformer ,which gives me 200 amp 5v .,can this possible?
posted by sudhir shingare 16 Dec 2014