Technical Capabilities

SIGA standard design techniques result in a typical temperature rise of 60°C when operated at full load and in an ambient of 20°C.

The approximate temperature rise at other loads can be estimated from the data in graph one. The actual temperature rise will depend on the general condition under which the transformers are operated and in particular the ambient temperature, the amount of ventilation available and the fixing method are important factors.

The regulation of a transformer – the output voltage drop on load – is calculated as follows:

The regulation varies with the size and VA rating of the transformer, and the typical regulation of a SIGA 50 Hz toroidal transformer is shown in graph two. If further technical detail or advice is required please contact SIGA technical sales department who will be pleased to assist.

The technical data is provided in good faith, as a general guide only, and due to the many factors which can effect its accuracy, users should satisfy themselves as to the validity of the information for their particular application.

No responsibility can be accepted by SIGA for any problems caused by errors in the technical data. When a transformer is used with a rectifier load, as in power supply applications, the AC rating of the secondary winding depends upon the DC output required and the type of rectifier circuit in use. The relationship between the AC secondary rating and the DC output for some common circuits is shown below when capacitor smoothing is required.

The figures quoted are an approximate guide only, and for more precise results, account must be taken of the rectifier forward voltage drop and the effect of the smoothing capacitor on the current form factor and ripple voltage. If a voltage regulator is being used, account must be taken of the regulator dropout voltage.

SIGA supply the following:
Standard toroidal transformersCustom wound toroidal transformers,
Bobbin wound laminated transformers, Ferrite cored transformers,
Potted transformers, Medical isolating transformers,
Foil wound coils and special assemblies