Specifications

Publication 1794-SG002D-EN-P - May 2012
68 Select a FLEX I/O Power Supply
The 1606 switched mode power supplies are capable of supplying a maximum of
up to 40 A at 24V DC and can be used as an alternative when more power is
needed.
Digital Input Modules require supplied 24V DC (19.2…31.2V DC) and
consume the currents listed in the module specifications.
Digital Output Modules require supplied 24V DC (19.2…31.2V DC) and
consume the currents listed in the module specifications plus the total current
consumed by their loads. The load current is limited by the maximum load
current and surge listed.
Combination Digital Modules have a combination of inputs and outputs. The
current load should be determined as described for the combined input and
output specifications listed.
Analog Input Modules require supplied 24V DC (19.2…31.2V DC) and
consume the currents listed in the module specifications. In addition, adequate
power must be supplied to the 1794-IE8 and 1794-IF4I transmitters to deliver
input terminal voltage or drive 20 mA into the input impedance listed. This
power source may be the same as the module power and can be included in the
power supply calculated.
Analog Output Modules require supplied 24V DC (19.2…31.2V DC) and
consume the currents listed plus the total current consumed by their loads. The
load current is limited by maximum current or resistive load permitted per
channel.
Combination Analog Modules have a combination of analog inputs and
outputs. The current load should be determined as described previously for the
combined modules and output specifications listed. The output load current is
limited by the maximum current or resistive load permitted per channel. In
addition, adequate power must be supplied to the 1794-IE8 and 1794-IF4I
transmitters to deliver input terminal voltage or drive 20 mA into the input
impedance listed. This power source may be the same as the module power and
can be included in the power supply calculation.
Counter Modules require module power, transmitter input power, and in some
cases output load power. If output load power is required, use a separate power
supply for output load power for noise immunity.
Power Requirements and Transformer Sizing
• Use the real power value in watts for determining the amount of heat
dissipation you will have inside the enclosure.
• Use the apparent power value in VA for estimated power distribution
sizing.
• Use the transformer load value in VA of each power supply plus all other
loads on a transformer to determine the required transformer size.