i used this way to make it happen
i add onther modbus to the new page
and on the form load i wrote this code
Private Sub Monitor_Load(sender As Object, e As EventArgs) Handles MyBase.Load
ModbusTCPCom1.IPAddress = MainForm.ModbusTCPCom1.IPAddress
ModbusTCPCom1.TcpipPort = MainForm.ModbusTCPCom1.TcpipPort
End Sub
is there another way?