Cadac J-Type Installation & User Manual Download

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APP-IV

J-Type

Revision J2005-2

Re-calibrating the 5568 Over-voltage Protection board

5568 set too low.

Adjust the potentiometer on the 5568 card by a few turns clockwise.

ii)

Increase the “O/P voltage adjust” potentiometer on the 48V regulator, until
there is 50V across the O/P capacitors.

iii) If the PSU “trips” before 50V is reached, repeat sub-procedures (i) to (iii).
iv) When the voltage across the O/P capacitors stays at 50V, very slowly turn

the potentiometer on the 5568 card ‘anti-clockwise’ until the PSU “trips”. The
card is now calibrated.

10. 5568 card set too high.

Check that you measure 50V across the O/P capacitor. If not, adjust the “O/
P Voltage Adjust” on the 48V regulator card until you get 50V across the O/P
capacitors.

ii)

Very slowly turn the potentiometer on the 5568 card ‘anti-clockwise’ until the
PSU “trips”. The card is now calibrated.

11. With the power OFF, turn the “O/P Voltage Adjust” potentiometer on the 48V reg-

ulator card ‘anti-clockwise’, by a few turns so that the 5568 card does not “trip”
the PSU when the power is turned ON.

12. Turn on the power and reset the “O/P Voltage Adjust” potentiometer on the 48V

regulator card so that you measure exactly 48V across the O/P capacitor.

Fault-finding tests

13. Check the green LEDs (Mains OK and O/P OK) on the power blocks. These

LEDs should light when the push to start button is pressed.

14. If either of the red LEDs “over-voltage” or “current limit” are illuminated, return

the power block for replacement (NOTE: DO NOT attempt to service the blocks.
Lethal DC-voltages are exposed underneath the cover.)

15. If MAINS OK LED does not come on, check the fuse. The fuse should only be

replaced with a 10A HBC TYPE T fuse.

16. If MAINS OK LED is illuminated but O/P OK LED is not, check the 15-way ‘D’-

connector on the PSU block is tightened. Check that the connector on the 8023
control card is pushed in all the way.

17. If the O/P LED is still not lit, remove the 15-way ‘D’-connector and link pins 9 - 10

and 1 - 7 on the PSU. If the PSU starts, the 8023 card or its wiring is fault. If the
PSU is still not working, it should be returned to the factory.

18. Check the fan (on back of PSU-block) is running. If it is not the PSU will overheat

and shut down or not provide full O/P capability. The fan can become stuck if
subjected to a hard knock - try to free the fan with the power turned OFF. If the
fan does not come on, return the PSU to the factory.

19. If the PSU shuts down when connected to the console, check that each PSU-

block can deliver approximately 103A and start into 90A. With the PSU discon-
nected from any outside loads, check that there is no reference to mains earth
from the 13V and 48V rails.

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There are times during the operation of a digital control system when things happen
that are unexpected. A data message may be formatted in an unexpected manner or
a hardware device may report an expected condition. These events may be trivial in
that they will not affect the overall operation of the system or they may be fatal in that
the system can no longer continue to function. The CADAC consoles have a system
of logging these unexpected events (and some of the user actions) in the battery
backed memory of the Central Control Module. The log reports these events in a way
that does not affect the operator progressing through the performance of the show so
3 different event categories are defined: