Typically an RPS Error is an issue involving a wiring connection, dust obstructing the optic sensors, or a faulty sensor. After clearing the obstruction, the lathe may need to be reset.
These pictures show what to expect inside the headstock. Attached are FAQ help sheets on the RPS state error symptom you are getting and how to clear or replace the sensor.
There are four files attached. The first three are relevant to your symptoms. The fourth one is there of illustration purposes to get to the sensor, and replace if necessary.
DVR.FAQs check Run Low RPM
DVR0 ERROR DVR RPS State Error0
DVR1 ERROR DVR RPS State Error1 STAGE 2
DVR2 ERROR Replacing the RPS Rotor Position Sensor
RPS0 means the connection is open from the 5 pin ribbon cable on the board to the sensor board. The cable is usually zip tied to the sensor board so that connection is not like a problem, just the one on the board. RPS1 means something obstructing the optics (dusty).
Please reply with your ship to address, serial number of the lathe, and if under warranty, dated proof of purchase receipt. If out of warranty, give us a call with a credit card.