Rockwell Automation 1440-VDRP06-00RH XM-160/161/162 Direct Vibration Module - Manual (Page 30)

Publication GMSI10-UM025C-EN-P - August 2010
22 Installing the XM-160/161/162 Direct Vibration Module
The XM-161 requires an external DC power supply to provide loop power.
The DC power supply must meet the following requirements:
• Minimum: 7V dc
• Maximum: 36V dc
To determine the minimum voltage across the total loop, add the resistance of
all loads in the loop, and determine the minimum operating voltage using the
following formula:
The measurements that the 4-20mA output tracks and the signal levels that
correspond to the 4mA and 20mA are configurable. Refer to 4-20mA Output
Parameters (XM-161) on page 70 for a description of the 4-20mA parameters.
Wire the loop-powered 4-20mA connection to the terminal base unit of the
XM-161 as shown in Figure 2.10. A 250 ohm resistor is the recommended
load.
EXAMPLE
A single PLC input channel with a resistance of 250 ohms,
combined with a field wire resistance of 50 ohms gives a
total resistance of 300 ohms.
Voltage minimum = 7 + (.0226A x 300 ohms)
Voltage minimum = 13.78V dc
ATTENTION
The 4-20mA output shields must be grounded at a single
point. It is recommended that where possible the cable
shield be grounded at the equipment wired to the 4-20mA
output and not at the XM terminal base.
Voltage minimum 7 .0226A total resistance in ohms Ч ( ) + =