Hello,
I have a transformer PT01-3 and I want to use it to measure voltage.
The datasheet is attached.
There is a current ratio specified (1mA/1mA) but no voltage ratio.

Does it mean that when I connect 230V on the primary side, I will get the same voltage on the secondary side?
I measured resistance on both primary and secondary side and they are the same (about 120 Ohms).

Thanks in advance for advice!

 

AC potential transformers are used to measure HV applications in order to monitor the HV source, they can have many kinds of secondary's
Usually known as a current transformer and never used without a burden of some kind, otherwise Very high voltages can appear on the secondary.

https://www.tutorialspoint.com/what-is-potential-transformer-p-t-and-how-it-works

 

https://www.micro-transformer.com/pcb-mounting-voltage-transformer-zmpt101l.html
is another alternative.
It acts as a 2mA:2mA current transformer, so it can be used on any voltage just by selecting the primary resistor.

 

https://hustimhouse.blogspot.com/2019/09/ct-sensors-arduino-thousand-hundred.html
CT&PT Sensors - Use Arduino to measure voltage and current

ADDED:

Thank you! I don't understand the wiring of J1 - shouldn't a secondary winding be there too?

Pins 1 and 2 are secondary winding. Primary winding is mains wire going through hole of transformer.

And one more question - if I want to connect it to 3.3V microcontroller, what Zener diodes shall I use? For 1.65V?

Z1 and Z2 are transient voltage suppressors. For Vps=3.3 V you should use not PSD05, but PSD03.

 

Thank you! I don't understand the wiring of J1 - shouldn't a secondary winding be there too?

 

And one more question - if I want to connect it to 3.3V microcontroller, what Zener diodes shall I use? For 1.65V?

Thanks