Rockwell Automation 6186M-xxxx Industrial Performance Monitors User Manual - Manual (Page 17)

Rockwell Automation Publication 6186M-UM002B-EN-P - March 2012 17
Installing the Monitor Chapter 2
Application Information
The circuit parameters of associated field-wired apparatus for use in hazardous
locations shall be coordinated with the host product such that their combination
remains nonincendive. The industrial performance monitors and USB peripheral
devices shall be treated in this manner.
Each industrial performance monitor provides two separately powered USB
ports. The circuit parameters for each USB port are found in tables on
page 15
and page 16 .
For the comparison of C
a (USB)
and C
i (peripheral)
, use the capacitance of each
individual connected USB peripheral device and its associated cable C
cable
.
For the comparison of L
a (USB)
with L
i (peripheral)
, use the inductance of each
individual peripheral device and its associated cable for L
cable
.
If cable capacitance and inductance are not known, the following values may be
used:
C
cable
= 60 pF/ft (197 pF/m)
L
cable
= 0.20 μH/ft (0.66 μH/m)
IMPORTANT Circuit parameters of USB peripheral devices and their associated cabling must
be within the limits in the tables on
page 15 and page 16 for the devices and
their cabling to remain nonincendive when used with the USB ports of
industrial performance monitors.