Rockwell Automation VersaView 1200P Integrated Display Computers for Hazardous Locations - Manual (Page 15)

VersaView 1200P Integrated Display Computers for Hazardous Locations 15
Publication 6183H-IN001E-EN-P - July 2007
Required Circuit Parameters for USB and PS2 Peripheral Devices
Parameter Value Parameter Definition
V
max (USB)
V
max (PS2)
5.25V dc
(minimum) Maximum applied voltage rating of each peripheral device. V
max
of each USB
peripheral shall be greater than or equal to V
oc (USB)
in the VersaView 1200P
USB and PS2 Port Circuit Parameters table on page 14.
V
max (per ipheral)
≥ V
oc (USB)
and/or V
oc (PS2) ,
as appropriate.
I
max (USB)
1.0 A
(minimum)
Maximum current to which each USB peripheral device can be subjected. I
max
of each USB peripheral shall be greater than or equal to I
sc (USB)
in the
VersaView 1200P USB and PS2 Port Circuit Parameters table on page 14.
I
max (USB peripheral)
≥ I
sc (USB)
I
max (PS2)
2.2 A
(minimum)
Maximum current to which each PS2 peripheral device can be subjected. I
max
of each PS2 peripheral shall be greater than or equal to I
sc (PS2)
in the
VersaView 1200P USB and PS2 Port Circuit Parameters table on page 14.
I
max (PS2 peripheral)
≥ I
sc (PS2)
C
i (USB)
20 µF Maximum allowed total capacitance of each separate USB peripheral device
and its associated cable. C
i
of each separate USB peripheral device and C
cable
of its associated cable shall be less than or equal to C
a (USB)
in the VersaView
1200P USB and PS2 Port Circuit Parameters table on page 14.
C
i ( USB)
+ C
cable (USB)
≤ C
a (USB)
C
i (PS2)
20 µF Maximum allowed total capacitance of all simultaneously connected PS2
peripheral devices and their associated cables. The sum of C
i
of all
simultaneously connected PS2 peripheral devices and C
cable
of their
associated cables shall be less than or equal to C
a (PS2)
in the VersaView 1200P
USB and PS2 Port Circuit Parameters table on page 14.
(C
i
+ C
cable
)
PS2 / 1
+ (C
i
+ C
cable
)
PS2 / 2
≤ C
a (PS2)
L
i (USB)
L
i (PS2)
3.11 µH Maximum allowed total inductance of each peripheral device and its
associated cable. The sum of L
i
of each peripheral device and L
cable
of its
associated cables shall be less than or equal to L
a (USB)
or L
a (PS2)
as
appropriate in the VersaView 1200P USB and PS2 Port Circuit Parameters table
on page 14.
(L
i
+ L
cable
)
USB1
≤ L
a (USB)
(L
i
+ L
cable
)
USB2
≤ L
a (USB)
(L
i
+ L
cable
)
PS2/1
≤ L
a (PS2)
(L
i
+ L
cable
)
PS2/2
≤ L
a (PS2)