DF56 – User’s Manual
4
DF56 – POWER SUPPLY FOR
BACKPLANE 20 – 30 VDC
Description
This redundant power supply works independently or with another redundant power supply module
to assure a constant power supply to the application.
When two redundant power supplies are used, if one of them fails, the backup will automatically
assume the operation. A relay is provided to indicate failure on each power supply giving the user a
chance to replace the faulty one.
This module has two voltage outputs:
a) 5 Vdc @ 3A distributed by Power Lines in the Inter-Module-Bus (IMB) through racks to supply
module circuits.
b) 24 Vdc @ 300mA for external use through terminals 1B and 2B.
The DC applied voltage and the 5Vdc and 24 Vdc are isolated.
Installation and Configuration
For systems based on DF92 and DF93 racks, with DF90 and DF91
Redundant mode
Splitting Power concept: In this situation, two modules will supply power to a bus segment. If one
of them was turned off or fails, the other power supply must be able to supply energy, alone, to the
segment.
Expansion of load capacity by adding power supplies or pairs of redundant power supplies
If the system consumption is greater than 3A, it can be subdivided in up to 8 groups sized for
consumption of up to 3A each, and each group is individually powered by a power supply, or
redundant pair of power supplies. More details on the Power supplies positioning topic.
Power supplies positions in the racks
On DF92, the pair of redundant power supplies must be installed in the first and second slots.
On DF93 is recommended the placement of the redundant pair in the first and second slots, but it
can be installed in any slots if necessary.
Configuration of CH1 jumper
The DF56 CH1 jumper always must be connected to the Rposition.
For systems based on DF1A and DF78 racks
Single Module: Less than 3 A are required.
There is an address restriction related to the location of the power supply. This restriction is the first
rack (address 0) must have a power supply module in the first slot. The CH1 jumper (power supply)
must be set in the Eposition.
More Than One Module: More than 3 A are required.
For systems based on DF1A rack they must be placed in the first slot of the rack. Jumper W1 on
the rack that has the new power supply must be cut. Every new power supply will only supply
energy to the rack in which it is located and, with the jumper cut off, it will not supply energy to the
previous racks. All modules must have the CH1 jumper (power supply) set in the Eposition.
Redundant Mode:
In redundant mode, the power supply modules must be placed in the first and third slots of rack
DF1A or first and second slots of rack DF78. In both, the CH1 jumper (power supply) must be set in
the Rposition. In this condition, the power supply modules will split the power. This topology is
called “split power mode”.
