Apply an 4-20mA input to multi Atv630

[Simon_P]

Hello all,

I have a question on how to wiring the pressure transmitter (XMLR010G1P25) 4-20mA analog signal to 2 VSD (ATV630)

I connect the 4-20mA signal to the First VSD AI3 terminal and the COM terminal to the Second VSD AI3, and the COM terminal connected to the External Power Supply 0V terminal.

Both VSD AI3 configure to 4-20mA 

However, only the First VSD read the analog signal.

[Bastian_Schmitz]

One pressure probe with 4..20mA output could not be directly connected to two devices. You could connect the probe to the first drive and and forward the pressure value via Analog Output to the second drive. 

[Simon_P]

Thank you for your reply and help.
Since I have used other brand VSDs (like abb, danfoss, AB) in other projects.
Those brands can connect the 4-20 mA analog input signal in series with multi VSDs and it works.
So I wonder if the ATV630 can also work in this case.
There is a problem which is the first VSD power failure or switch off, then the pressure value cannot forward to the second device through the analog output, If I use your suggestion.
Unfortunately,  Telemecanique does not provide the 0-10V pressure transmitter with 2 PNP Output, otherwise I may use 0-10V control instead.

[Hennie_Smith]

Hi Simon,

If it is critical to always have both VSD's get the signal I propose using a 4-20mA signal splitter. There are a number of terminal suppliers that has them

Regards,

Hennie