Westermo RM-115S - Manual (Page 9)

115S Serial I/O Module User Manual
man_115S_1.14.docx Page 9
example, the first input is connected to terminals AIN1 (positive) and AIN2
(negative).
The two types of input cannot be mixed - all inputs must be either “grounded” or
“floating”.
Inputs can also be selected as mA current, or voltage input - all inputs must be the same,
either all current or all voltage. The scale of each analog input is chosen during hardware
configuration, with scale options as follows:
Voltage input scale options: [0 to 5V], [0 to 10V], [1 to 5V]
Current input scale options: [0 to 10mA], [0 to 20mA], [4 to 20mA]
For compatibility with E-Series modules, 4-20mA current is recommended. See section
4.4 for more information on compatibility.
The values on the analog input are decimal 16,384 (hex 4000) for minimum signal (0%)
and decimal 49,152 (hex C000) for maximum (100%).
The analog channel will measure over-scale, up to 150% which will have value 65,536
(hex FFFF). For 4-20mA signals, the channel will measure under-scale down to 0mA
which has a value of 8,192 (hex 2000). (See section 5.4 for hex to decimal conversion.)
The 115S-12 provides a 24V analog loop supply (“ALS”) for powering analog loops.
1.1.5 Analog outputs
The 115S-13 has eight analog output channels and can be configured to output voltage or
current. For current signals, “source” or “sink” can be selected. The scale of each analog
output is specified during configuration, with scale options as follows:
Voltage output scale options: [0 to 5V], [0 to 10V], [1 to 5V]
Current output scale options: [0 to 10mA], [0 to 20mA], [4 to 20mA], source or sink
• Voltage outputs are measured with respect to the ground terminal.
• Current source outputs are measured with respect to the ground terminal.
• Current sink outputs are measured with respect to the 24V “ALS” terminal.
Writing to the output register by the master produces the analog output. Minimum to
maximum signals (0 – 100%) are produced by register values from decimal 16,384 to
49,152 (hex 4000 - C000). (See section 5.4 for hex to decimal conversion.)
The analog channel can output over-scale, up to 150% corresponding to register value
65,536 (hex FFFF). For 4-20mA signals, the channel can output under-scale down to
0mA from a register value of 8,192 (hex 2000) or less. Note that the over-scale output is
limited by the maximum levels capable of the 115S module (12V or 24mA).