Technical evaluation of transformers

You can evalute the transformer from the various manufacturer with following parameters:

1. Transformer Losses

2. Auxiliary Power Consumption

3. Transformer Efficiency at various loads.

4. Transformer Regulation.

5. No. of Cooling units provided.

6. Percentage Impedence (if not specified in the specification)

7. Winding and Top Oil temperature

I thought above perameter are well enough for evalution of transformer.

for forther query please inform.

Thanks for prompt response and shall use the points given.

Hi VASU,

Are you looking to size a transformer for a load, or actually quality test a transformer? If you are sizing to a load here are the basics you need to know.

1) 1PH or 3PH

2) Voltage needed on the Primary side (source voltage available)

3) Voltages needed on the Secondary side (load voltages)

4) Maximum current the load will pull, if it is an inductive(motor load) then what is the Inrush current at start up of the motor - if you don't know take nominal current and double it so the transformer will only be loaded 50%) . A general rule of thumb is 60-70% loading for transformers.

Thanks for your prompt response but we need points for technical evaluation based on the tech.specs in the tender.

Thanks for your prompt response but we require points for technical evaluation.

The data sheet is generally ok. But need to include many more. Add Transformer losses as a vital information, this is required to braing costa of different bid at PAR.

Dear Vasu,

You are asking for Technical Evalution of Transformers. It means you have technical specification of transformer with you. First of all ensure all parameters proposed by the vendors are matching with the technical specification. For further evalution you may considered parameter as mentioned earlier.

If you are still have any query please let us know.

Regards

Manish Ahuja