
FXP1500-32G AC-DC Front-End
& FXR-3-32G Power Shelf Data Sheet
Paralleling Front-Ends:
For parallel use in minimal configuration systems, only the inhibit pins must be shorted to logic GND. All other pins can be left
open. The power supplies will share the output current automatically (droop current share).
For parallel applications without I 2 C bus, but the use of all other features, it is recommended to connect all logic GND’s on a
backplane together, to connect all V o2 -, all V o2 + and to leave the internal GND’s open.
The sense wires can be left open or connected to a common load point, the synch-start pin can be left open or connected to a
synch-start circuit, the inhibit pins can be connected together or used individually. All I 2 C signals (T1-T5, S1, and S2) can be left
open.
Use of a small foil capacitor > 3μF directly at the power outputs of each unit is recommended in order to prevent voltage drops at
the hot plug. For additional information on paralleling see the following Rack (Power Shelf) section.
Racks
(FXR-3-32G Power Shelves)
Each rack (power shelf) is 1U high with backplane and designed for up to three front-end models in parallel or in n+1 operation.
Each power shelf has:
? Generous copper bus bars for low-loss current distribution.
? Output terminals with two M4-screws on each power tab.
? Two fast-on contacts for system earthing.
? Address coding over five pole DIP switch on each unit, 37-pin D-Sub connector with I 2 C-lines, monitoring signals and
?
support functions.
Provides a start-up synchronization circuit and EMV filters.
FXR-3-32G Power Shelf Front View
Overall Mechanical Dimensions (FXR-3-32G Power Shelves)
FXR-3 Mechanical Data (W, H, D)
17.7” (449.6 mm) x 1.7” (43.1 mm) x 14” (355.6 mm)
BCD.00021 Rev.AA, 31-JAN -11
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