Rockwell Automation 2711P PanelView Plus Terminal User Manual - Manual (Page 33)

Publication 2711P-UM001J-EN-P - November 2009 33
Installation Chapter 2
Application Information
Per the National Electrical Code the circuit parameters of
nonincendive field wiring apparatus for use in hazardous locations
shall be coordinated with the associated nonincendive field wiring
apparatus such that their combination remains nonincendive. The
PanelView Plus terminal and the USB peripheral device shall be
treated in this manner.
The circuit parameters of the PanelView Plus terminal USB port are
given in Table 1. The USB peripheral device and its associated cabling
shall have circuit parameters with the limits given in Table 2 for them
to remain nonincendive when used with the PanelView Plus terminal
USB port. If cable capacitance and inductance are not known the
following values from ANSI/ISA-RP 12.06.01-2003 may be used:
C
cable
= 197pF/m (60 pF/ft)
L
cable
= 0.7 µH/m (0.20 µH/ft)
Nonincendive field wiring must be wired and separated in accordance
with 501.10(B)(3) of the National Electrical Code (NEC) ANSI/NFPA 70
or other local codes as applicable.
This associated nonincendive field wiring apparatus has not been
evaluated for use in combination with another associated
nonincendive field wiring apparatus.
Symbol Definitions
V
oc
Open circuit voltage of the host USB port.
I
sc
Maximum output current of the host USB port.
V
max
Maximum applied voltage rating of the USB peripheral device.
V
max
shall be greater than or equal to V
oc
in Table 1. (V
max
≥
V
oc ).
I
max
Maximum current to which the USB peripheral device can be subjected.
I
max
shall be greater than or equal to I
sc
in Table 1. (I
max
≥
I
sc
).
C
i
Maximum internal capacitance of the USB peripheral device.
C
a
Maximum allowed capacitance of the USB peripheral device and its
associated cable. The sum of C
i
of the USB peripheral device and C
cable
of
the associated cable shall be less than or equal to C
a
. (C
i
+ C
cable
≤
C
a
).
L
i
Maximum internal inductance of the USB peripheral device.
L
a
Maximum allowed inductance of the USB peripheral device and its
associated cable. The sum of L
i
of the USB peripheral device and L
cable
of
the associated cable shall be less than or equal to L
a
. (L
i
+ L
cable
≤
L
a
).