Tel: +44 (0)1254 381869
Fax: +44 (0)1254 381674
Email:
Admagnetics Bolton Avenue, Huncoat, Accrington, Lancashire
BB5 6NJ, United Kingdom
Fax: +44 (0)1254 381674
Email:
Admagnetics Bolton Avenue, Huncoat, Accrington, Lancashire
BB5 6NJ, United Kingdom
Choosing the right voltage transformer is about more than just the required voltage.
Scientists are discovering new ways to control transformer temperatures, thanks to innovative nanomaterials.
Technical Details
Although a transformer is a relatively simple piece of electrical equipment there are numerous factors which must be taken into account in the design and manufacture to ensure that it will give safe and reliable service when used for the task that it is intended. An electrical transformer properly specified, designed, manufactured and installed should give many years of good service.
An electrical transformer essentially consists of a magnetic core upon which are wound two (or more) coils of insulated copper wire, suitably located with respect to one another and usually termed the primary and secondary respectively. The ratios of these windings determining if it is a step up or step down transformer with respect to the input voltage or an isolating transformer if the ratio is 1:1.
Power-transformers used in iron cored transformers are given insulating coatings to develop adequate magnetic insulation between layers in the stacked core, thus reducing the interlamination eddy current loss to an acceptable level; this keeps the total watts loss of the stack to a minimum. The use of grain oriented steel enables cores to be used at higher flux densities, thus giving higher efficiency, smaller size or reduced weight, compared to transformers using lower grade steel.
Stamped power-transformers come in a variety of shapes and sizes, the most popular type being 'E' and 'I' power-transformers. This shape gives excellent economy with acceptable losses per kilo of material used for a given transformer design. There are several grades of this type of power-transformers available which can be used to either reduce physical size or improve efficiency.
When a voltage is applied to the primary windings (with the secondary open circuit) a small current will flow, this magnetises the core and supplies the iron loss and is called the no-load current. The iron losses are constant in the transformer; the losses that vary with load are the copper losses. When a load is connected to the secondary, increased current flows in the windings and copper losses become more significant. The ability of the transformer to dissipate the losses determines the eventual temperature rise. Other losses are present such as stray eddy currents in the core clamps, bolts, dielectric loss in insulation, etc., although normally these are of a smaller nature.
Click for more details on transformer data.
Power-transformers used in iron cored transformers are given insulating coatings to develop adequate magnetic insulation between layers in the stacked core, thus reducing the interlamination eddy current loss to an acceptable level; this keeps the total watts loss of the stack to a minimum. The use of grain oriented steel enables cores to be used at higher flux densities, thus giving higher efficiency, smaller size or reduced weight, compared to transformers using lower grade steel.
Stamped power-transformers come in a variety of shapes and sizes, the most popular type being 'E' and 'I' power-transformers. This shape gives excellent economy with acceptable losses per kilo of material used for a given transformer design. There are several grades of this type of power-transformers available which can be used to either reduce physical size or improve efficiency.
When a voltage is applied to the primary windings (with the secondary open circuit) a small current will flow, this magnetises the core and supplies the iron loss and is called the no-load current. The iron losses are constant in the transformer; the losses that vary with load are the copper losses. When a load is connected to the secondary, increased current flows in the windings and copper losses become more significant. The ability of the transformer to dissipate the losses determines the eventual temperature rise. Other losses are present such as stray eddy currents in the core clamps, bolts, dielectric loss in insulation, etc., although normally these are of a smaller nature.
Click for more details on transformer data.
General Transformer Data
Factors which affect Transformers and other electrical components
Power Transformer Product Sheets
Power Transformers and Wound Components
Our product range of transformers and wound components extends from small components rated at a few VA up to power transformers rated at around 1MVA.
Read more about how wound components are used.
We are pleased to offer a number of standard range transformer data sheets and application notes. Data sheets can be downloaded from this page and application notes obtained by contacting our Sales Manager, Steve Garner, phone number 07850 816363 or by e-mail at steve@admagnetics.co.uk