We have a 2-phase system where the phase are 115V 50hz and no neutral.

Is it possible to meassure both phases.

When hardware installing one on the phases should be in UN right?

Hi :

You mean your system has two L lines, no N line, yes?

If so ,you can measure it by a single-phase power meter like this https://www.iammeter.com/newsshow/single-phase-three-wires-system

Ive made a picture of how i am planning to wire it.

I have the 3-phase meter already.

Will this work?

Hi:

In fact, this system can be thought of as a single-phase system.
You can just connect one L line to Ua and another L line to the UN.
Just clamp the CTa one one L line, you do not need to clamp two CTs on both L lines, because there is only one loop in this case.
Even if you clamp to CTs on both L lines, they would be the same readings.

you can install the power meter like this 

I have now bought the WET3080, i will try it out and have the WET3080T as a spare if it does not work, i will reply with the results =)

Thanx!!!