HP DC5850 - Manual (Page 62)

5-12 www.hp.com Technical Reference Guide
Input/Output Interfaces
5.7.2 USB Cable Data
The recommended cable length between the host and the USB device should be no longer than
sixteen feet for full-channel (12 MB/s) operation, depending on cable specification (see
following table).
NOTE:
For sub-channel (1.5 MB/s) operation and/or when using sub-standard cable shorter lengths may be
allowable and/or necessary.
The shield, chassis ground, and power ground should be tied together at the host end but left
unconnected at the device end to avoid ground loops.
Table 5-8.
USB Cable Length Data
Conductor Size Resistance Maximum Length
20 AWG
0.036 Ω 16.4 ft (5.00 m)
22 AWG
0.057 Ω 9.94 ft (3.03 m)
24 AWG
0.091 Ω 6.82 ft (2.08 m)
26 AWG
0.145
Ω 4.30 ft (1.31 m)
28 AWG
0.232 Ω 2.66 ft (0.81 m)
Table 5-9.
USB Color Code
Signal Insulation color
Data + Green
Data - White
Vcc Red
Ground Black