Hello,

The link below is a FW-X240 Auto transformer stepup and stepdown.
www.outbackpower.com/pdf/manuals/fw-​x240.pdf

I looked on pdf file, I could not find which wire# is primary and secondary.
If it is step down, apply 240v on the winding# and will get 120v from another widnding. How do we verify which wires are used for step down voltage?

Thanks

ken

 

Ken,

The step down wiring is shown in section 1:9 of the manual. If you also look at the diagram on Section 1:5 it will show the colour codes for the transformer wires.

 

I didn't get why they call it autotransformer, if it has two separate and equal windings.

But with this info

"Two identical windings:
• Winding one is between leads #1 and #2
• Winding two is between leads #3 and #4
• The start for each winding are on lead #1 and on lead #3"

and the drawing on page 6 you know at least how it was built.

1 and 3 is the beginning of each winding, so in their diagrams they connect 2 to 3. Doing so you put both windings in series.
So if you want a simple step-up you connect 2 and 3 and put your 120VAC between 1 and 2. Then you'll have 240VAC between 1 and 4. Or you connect 240VAC to 1 and 4 and will have 120VAC between 1 and 2 (and 3 and 4). Correct?

 

Thank you very much.

ken