Transformer With Two Tap

If you move the tap settings you're only going to gain 10V or so.

What is your supply voltage?

The supply voltage is 15000v. Why we have two taps in the first place?

Where's the paperwork that came with the transformer?

Dear Lyn,

The paper work does not say much! Why do we have two taps? This is the first I am seeing a transformer with two taps. Best Regards, Page

Your supplier should idientify the values of each tap. Are you new to the business?

Call your supplier and explain that you don't know how to hook the transformer up properly.

Tap (transformer) - Wikipedia, the free encyclopedia

Thanks Lyn, I will contact the supplier regarding the 2 taps. Page

Dear Mr.Page

It appears the transfprmer is duel voltage transformer viz 15 KV/400 V and

20KV/ 400 V nominal.For your supply system of 15 KV please select tap 1 and you will get 400 Volts on the secondary (nominal) (300/15x20=400 ).You can adjust the tap 1 to position 15 KV or 15.5 KV or 14.5 KV as per your available system voltage to get almost 400 V on the secondary.

You are now getting 300 V as you are applying 15KV in 20 KV tap

Ok Ramasmi, if you are right then how do I know where the incoming voltage(15KV) is applyied to? To tap 1 (15,5kv, 15kv, and 14,5kv ) or tap 2 ( 20,5kv, 20kv, and 19,5kv)?Since both taps (1 and 2) are sitting on the top of the transformer and set originally from the factory to position 2( tap1 15kv, tap2 20kv)! Each tap has position 1,2 and 3. There is no such thing as transfer switch to switch the incoming voltage from tap 2 to tap 1 and apply what you are suggesting. Is the incoming voltage applyied to both taps(1 and 2)?How is the wiring inside this transformer in relation to both taps? I will keep trying to contact the suppliers( I am in Africa and I did not buy this transformer myself) as suggested by Lyn.

Thanks, Page

Dear Mr.page

You have to connect to tap 1 position 2 which is meant for 15 KV and measure the secondary voltage.If it is 400 volt leave it.If it is less connect to position 1 which is meant for 14500 V and if it is more connect to position 3 which is meant for 15500 V.

Better you check what is the incoming voltage at your supply point and connect accordingly

Normally manufacturer provides selector switch to choose the position 1,2,or 3.Please check with manufacturer

I moved the tap from position 2 to 3, 14,5kv, almost the same result. I think the transformer was made to receive 20kv as incoming voltage. I am pretty much sure that the manufacturer made just a mistake and shipped the wrong transformer. When we received the transformer the name plate was not attached to it. I am still wondering why do they make transformers with two taps?

you din't mention if you have connected to tap 1 instead of pre connected tap2.Unless you connect to tap 1 you wont get the required voltage of 400V nominal

Look Ramasmy, We have two Taps, TAP 1 and TAP 2 and each one has 3 positions, 1,2 and 3. Originally from factory (I guess) both taps were set to position 2. What we did yesteday was move TAP 1 from position 2 (15KV) to posotion 3 (14,5KV). Still we could not get the 400V on the secondary! The manufactures have not got back to me yet. Why two TAPs? Anybody knows?

Dear Mr.Page

As i mentioned earlier until and unless you connect your incoming supply to TAP 1 instead of existing Tap 2 you wont get 400 V out put irrespective of position 1,2,or 3

Regarding two TAPs, it is to fecilitate to suit different power supply in different countries whre 20 KV is also standard as 15 KV is staandard in your coun try

Dear Ramasmy: How do I connect the incoming supply on TAP1 ? !?!?Are you familiar with big power transformer?

What do you mean by ´Regarding two TAPs, it is to facilitate to suit different power supply in different countries where 20 KV is also standard as 15 LV is standard in your contry´?

Page

While waiting for the manufacturer to guide you, perform some experimentation.

Deciding on which tap to use is really dependant on knowing the turns ratio of the trafo.

You can energise the primary side with LV and measure the secondary voltages presented at each tap. This will give you further insite but you should still chat with the supplier as they should know (unless it is 60 years old, or emblazoned with Chinese text, or something like that)