How to change the turns ratio of transformer?

[Oli.P]

Hi Anupshetti,

I understand that your looking for a way to change the turns ratio of your Multisim Transformer in Multisim.

To do this, you will need to use the 'TS_XFMR1' component.  Once you have placed it on your schematic, double click and navigate to the 'Value' tab.  Here you will find the Primary-to-Secondary Turns Ratio field.

I hope that helps.  Please feel free to post back if there is anything else I can assist you with.

Regards,

[Marctrainer]

I can find where to change the turns ratio but how do I enter the ratio into the field? For my class problem I need a 10:1 transformer. If I select the transformer you mention in the post, how is 10:1 entered? If I enter 10:1 and go back to the field later, there is only a 10 in the window.

[Oli.P]

Hi Marctrainer,

Welcome to the Forums!

The turns ratio for a transformer in Multisim is defined using a decimal, not a ratio.  For example:

For a 1:5 ratio, treat it as a fraction 1/5, you would enter '0.2'

For a 3:4 ratio, 3/4, you would enter '0.75'

For a 10:1 ratio, 10/1, enter '10'.

For a 6:3 ratio, 6/3, enter '2'.

I hope that helps.

Best Regards,

[Marctrainer]

That does not help. What value do you enter? For example, for a 10 to 1 ratio, how would I enter that ratio?

[Oli.P]

The original post, answer, and my previous post detail exactly how to calculate the ratio.  In my last post I gave you an exact example of how to do a 10 to 1 ratio.

Here's a step by step guide:

1 - Place down the transformer on your design (e.g. TS_VIRTUAL or TX_XFMR).

2 - Double-click on the transformer.

3 - Select the Value tab

4 - Enter the desired ratio in the 'Primary-to-secondary turns ratio' box.

The ratio is derived exactly as described in my previous post (I've done a 10:1 example).  Here's each step to work it out:

To get a 10 (primary) to 1 (secondary) ratio - i.e. 1/10th stepdown transformer - i.e. 10:1.

Treat it like a fraction - i.e. 10/1

Then just turn the fraction into a decimal value: 10 divided by 1 = 10.

Therefore you enter '10' in the 'Primary-to-secondary turns ratio' box.

That will give you a 10 to 1 ratio transformer.

Alternatively, you can use a different component such as the '1P1S' from the Basic > Transformer family in the component database.  Again, double click on this and navigate to the Value tab.  This time, enter the number of turns for each coil individually.  So for your 10 to 1 transformer, enter '10' for 'Primary Coil 1' and enter '1' for 'Secondary Coil 1'

Regards,