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Inputs
Caution!
The maximum voltage that can be applied to an input
terminal is 25 VDC
The Axiom Plus provides 15 optically isolated inputs if analog input
is not used. The inputs can be configured to sink or source current
(5VDC – 25VDC, 2.7mA – 15 mA) in each of the three banks of inputs.
This allows connection to TTL, PLC’s, relays and mechanical
switches. Because the input circuits are isolated, they require a
source or power. The power can be provided from the Axiom Plus
built in 24VDC 400mA power supply or an external customer
supplied 5VDC – 24VDC power supply.
Note that inputs 13 and 14 serve also as inputs to the 14-bit
differential analog input. Because of this, these inputs have an input
impedance of 40 Kohms. These inputs can tolerate 5 volts common
mode with respect to Axiom Plus chassis ground. Proper operation
of these inputs will require 2.2Kv pull-up/pull-down resistors when
paired with single-ended outputs.
The diagrams on the following pages show how to connect the
Axiom Plus inputs to various devices.
Figure 9.1 - Axiom Plus Input Circuit Diagram
IN 2
IN 1
COM 1-6
2.2 K
2.2 K
INSIDE AXIOM PLUS
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9 - 1
I/O Connections
9
