Safety analog inputs (1734-ie4s), Input range, Scaling – Rockwell Automation 1734-IE4S POINT Guard I/O Safety Modules User Manual User Manual
Page 31: Input range scaling
Rockwell Automation Publication 1734-UM013J-EN-P - July 2014
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Safety Inputs, Safety Outputs, and Safety Data
Chapter 2
Safety Analog Inputs
(1734-IE4S)
Safety analog-input channels can be configured for current, voltage, or
tachometer inputs, and for input type: single-channel or dual-channel equivalent.
Input Range
You configure the module for the following voltage or current input ranges, or for
tachometer inputs.
• ±10V
• ±5V
• 0…5V
• 0…10V
• 4…20 mA
• 0…20 mA
• Tachometer (1…1000 Hz)
Scaling
The module converts input signals to the engineering units specified when you
configure the module. You set the High Engineering value and the Low
Engineering value to which the module scales the input signal before sending the
data to the controller’s application program.
IMPORTANT
If you are using the module with a GuardLogix controller, set the module’s
inputs to Single (default). Do not use the modules’ dual-channel equivalent
mode with the GuardLogix dual channel safety application instructions, as
dual-channel functionality is provided by the GuardLogix instructions.
IMPORTANT
When ±10V and ±5V ranges are selected, you must make sure that a
broken-wire condition is not a safety hazard. A broken wire causes the analog
value to transition to 0, which is within the valid input range. Therefore, status
bits will not indicate the broken-wire condition.
EXAMPLE
The module is configured as follows:
• Input Range = 0…10V
• Low Engineering value = 0
• High Engineering value = 10,000
If the incoming signal is 1V, the data is 1000.
If the incoming signal is 5.5V, the data is 5500.