Racal Instruments 1264C, User Manual

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1264C User Manual
Racal Instruments © 1998 Understanding The 1264C 4-3
Power Supply
Protections
The seven VXIbus power supply outputs are protected for:
·
Over-voltage
·
Over-current and short circuit
·
Over-temperature
The AC input of the power supply includes protections for:
·
Input current fusing
See Appendix A for specification details pertaining to the above
protections.
If any of the over-voltage or over-temperature protections are
active, the power supplies will shutdown. This means the supply
has turned itself off to protect the system. The AC Power switch
S100 must be cycled to clear the shutdown condition. If the supply
continues to shutdown then the external fault is still present.
If any of the over-current and short-circuit protections are active
the power supply will go into current-limit and the voltage on the
respective output may be reduced or at ground potential. These
protections are self-correcting and the respective output will return
to its nominal value when the fault is removed
Backplane
The Backplane (405130) serves several functions
·
Accommodates up to 6 C-size VXI.
·
Rigid mechanical interface which accommodates a lifetime
of insertions of VXI modules.
·
Mechanically connects (at E1 to E14) to the power supply
and distributes DC voltages and currents to VXI modules
(through P1 and P2).
·
Connects the VME communications interface across P1
and P2 to all slots.
·
Connects the VXI extension signals across P2 rows A and
C to all slots.
·
Connects to the system monitor board through a 14-pin
ribbon cable between J50 on the backplane and J301 on
the power supply assembly (407645).