PRT-E1500 with be the model number for the VFD drive for the spindle motor
various Chinese CNC machine builders make control boxes that look identical on the outside but the electronics inside can be very different
some use an all in one BOB & stepper drivers on a single board
others a BOB & individual stepper drivers
Photos of the inside showing the printed circuit boards will help identify what you have
some times they don't always install all the components to the BOB's PCB used in machines without a connector to plug in a touch probe
example of a BOB with some parts not installed
photo taken of the net showing the inside of a CNC machines control box
the PRT-E1500 VFD board is in the foreground
John