Specifications
67 Publication 1794-SG002D-EN-P - May 2012
Section
1.5
Select a FLEX I/O Power Supply
Step 4 – Select:
if power consumption exceeds the maximum for a single power supply,
install additional power supplies
FLEX I/O modules are interfaced to the I/O link through a FLEX I/O adapter
module with a built-in 24V DC input power supply. The FLEX I/O modules
receive power from the adapter/power supply through the backplane. The 120V
AC to 24V DC power supply (1794-PS13 or 1794-PS3) is also available for
powering the adapter/power supply.
Power Supply Definitions
Module Supply Voltage — This is typically either 120V AC or 24V DC
nominal voltage that is supplied from an external power source wired to the
module terminal base unit.
All Flex I/O adapters provide internal power to the maximum possible number of
8 Flex I/O modules. Power supply modules are required to provide 24V to the
adapters.
The 1794-PS13 power supply is capable of supplying a maximum of 1.3 A at 24V
DC. The output surge current is sufficient to drive four adapters with a surge of
23 A for 2 ms each operating at 24V DC.
The 1794-PS3 power supply is capable of supplying a maximum of 3 A
(1)
at 24V
DC. The output surge current is sufficient to drive six adapters with a surge of 23
A for 2 ms each operating at 24V DC.
Non-Allen-Bradley DC power supplies can also be used, but should operate
within the specifications for the devices they are powering. Size the power supply
by calculating the total current consumed by summing the currents for each of the
modules used for the power supply operating voltage applied.
General Specification Comparison
Catalog Power Supply
Input Voltage,
nom
Power Supply
Input Power
Apparent Input
Power, max
Transformer Load,
max
Output Current,
max
Output
Voltage, nom
Dimensions
(HxWxD), approx
1794-PS3 120V/220V AC 86 W 205 VA 250 VA 3.0 A 24V DC 87 x 94 x 69 mm
(3.4 x 3.7 x 2.7 in.)
1794-PS13 36 W 53 VA 90 VA 1.3 A 87 x 69 x 69 mm
(3.4 x 2.7 x 2.7 in.)
(1) This refers to horizontal mounting: 2.8 A maximum for all other mountings. Refer to the derating curve in the
installation instructions for that module.