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MOS Troubleshooting

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Mos Troubleshooting

Before initializing the MOS punch unit, verify that the lock function of the star plate wheel is in the "unlock" condition and the "Y Table" function is in the "park" and "low limit" condition. If any of these function are out of position, follow the procedure "1" described below. If they are in the right position, go to step 2.

  1. One function out of position
    • Switch off and on the CAMAC crate controller.
    • If the "Y Table" function is not park. Verify that the star plate wheel is locked (lock pin function "lock"). If locked, set the select key of the handset to position "3" and move the "Y Table" out until the "park" and "Low limit" Leds are both on.
      If the pin is not in the locked condition, be sure that the star plate has a locking notch in front of the lock pin. If not, switch off the CAMAC crate and move the star plate by hand, until the notch coincides with the lock pin. Be sure that the wheel is free to move before moving by hand. Switch the CAMAC "on".
      With the handset key in position "2", move the lock pin until "lock" and Upper Limit Leds are "on"
      Put the select key of the handset in position "3" and move the Y Table out until the "park" and "Low limit" Leds are both on.
    • Set the handset select key to function "2" and move the lock pin to "unlock" position.
    • In the LCU rack, press the "reset" button and wait until the lefmos LCU finish the boot script.
    • Start the MOS start up procedure in the Xterm window.
  2. Lock pin and carriage "Y" functions in position
    • Switch off and on the CAMAC crate
    • Switch off and on the MOS LCU
    • Wait until the lefmos LCU finish the boot script.
    • Start the MOS start up procedure in the Xterm window.
    • The star plate should start to rotate and after a complete turn, stop. Then it will move to the standby position and stop again.
      If the star plate rotate continuously, verify that the Leds column corresponding to Star plate wheel function in the patch chassis are increasing or decreasing. If they do not change, check the encoder signals and encoder cables from the Punch unit to the patch box.


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Last update: 30 Sep 2005 
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