Fault finding

Examining the MCU LCD display, status LEDs, the system configuration and current conditions, can solve many problems.

NOTE:  As with most cable connected ancillary equipment, it is the actual cable that is the most vulnerable part, particularly with a joystick where it can be trapped by the part under inspection, pulled if caught by machine motion, trodden on, run over, etc.  If any malfunction with the MCU occurs, the first step should be an examination of the cable. 

Suspect operation of joystick or buttons

There is a comprehensive test program for the MCU joystick operation and button function within UCCassist-2.  Plese refer to the UCCassist-2 user's guide (Renishaw part number H-1000-5224) for details.

The joystick will not move the CMM

Several conditions have to be satisfied before joystick controlled moves can be made:

  • That is connected to the UCC and has been set up in the configuration file
  • The joystick should be 'enabled'
  • The MCU ‘joystick enable' button must be pushed
  • The axis locks must not be applied
  • The CMM application software must be in manual (joystick) mode
  • The probe must not be ‘deflected', unless probe override is on
  • No limit switches should be open, unless disabled
  • The CMM position must be inside all ‘soft limits' if these are enabled

The speeds are too low or too high

Check the joystick speeds and accelerations that are set in the UCC configuration file, are correct.

  • Check the operation of the fast/slow switch. Higher speeds will be obtained when this switch is active

The motors disengage during joystick operation

If the joystick max speed is set to a high value, the machine may be able to exceed the maximum move speed to cause an overspeed error.

  • If the joystick max fast acceleration is set to too high a value, the motor signals may attempt to exceed the overdrive limits and cause an overdrive fault
  • If the system proportional gains are set too high, or the velocity gains are too low, an overdrive fault may occur

Speed override does not work correctly

  • This feature must be enabled separately from the general joystick enabling: it is an entry in the UCC configuration file

NOTE: Speed override ONLY works on DCC moves and scanning.  It is not operational when the MCU is in manual (joystick) mode. 

Servos will not engage

  • E-STOP not connected correctly
  • E-STOP still asserted
  • An outer limit switch is activated

No screen display

  • Check cable connection