How to control machinery and equipment with a single remote computer?

Which control sys did you mean ?  for one machine or more than one ?

I will chose SCADA  because the PLC alone it will simply run a program. Yes you can add buttons to control a procces in real time only with PLC but SCADA is even more advanced than that because it can inform you about the situation of the entire process.

there are a lot of options for ceterelized control systems which can work as master and slaves (for small units ) and SCADA (supervisory control and data acquisition) is a system operating with coded signals over communication channels so as to provide control of remote equipment (using typically one communication channel per remote station). The supervisory system may be combined with a data acquisition system by adding the use of coded signals over communication channels to acquire information about the status of the remote equipment for display or for recording/controlling/analyzing  functions.

the remote terminal units (RTU) will work as a slave.

there are many ways to convert the comunication protocol to match3rd party components with the center or (cpu) 

we can control machinary and equipment  using single remote computer by using CAM  software this called  flexbile manufacture system  we can use   pro- engineer wildfire sofware as example

Using the work of server and give all machine IP