Metric Halo 2882 operating guide - Manual (Page 27)

Mobile I/O User’s Guide
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accesses and meter updates slow down. If you are experiencing bus over-
loads, you can always add a second FireWire bus with a third-party FireWire
card (PC-Card or PCI card depending on your machine), and offload one or
more devices to the second bus.
P OWER
One of Mobile I/O’s great strengths is the flexibility of its power system.
Mobile I/O can be powered from any DC source (including bus power) in
the range of 9V to 30V as long as it provides 12 Watts of power. The DC
input on Mobile I/O is a 2.1mm coaxial power connector, center positive. So
if you are powering the unit with a third party power source and it supplies
9V, the power source will have to provide 1.4 amps of current. If you are
powering the unit with 12V, the power source will have to provide 1 amp of
current, and so on.
The Mobile I/O ships with a world-ready 24 volt, 2 amp power supply. You
can plug this supply into any AC power source from 90V to 240V, 50Hz -
60Hz, using an appropriate IEC power cord, and it will supply the proper
power to the Mobile I/O on the 2.1mm coaxial power connector. Mobile I/O
will automatically supply the extra power to the FireWire bus. This means
that the Mobile I/O and its power supply can be used to power other
bus-powerable FireWire devices including hard-drives, hubs, and other
Mobile I/O units.
Since Mobile I/O is DC powered, you can also power up the Mobile I/O
using the FireWire bus or another DC source. The Mobile I/O uses 12 Watts
of power, so the device supplying the bus power must be capable of sourc-
ing that much power. Most desktop Macs provide more than enough power
for Mobile I/O and one other low power device. Most laptops provide
enough power for Mobile I/O, but not enough for Mobile I/O and another
bus-powered device at the same time. If you are using a Powerbook com-
puter, you should not expect to be able to power both the Mobile I/O and a
hard drive from the computer. The power capabilities of individual comput-
ers vary, so you will have to test the complete system to determine exactly
how much your computer can handle.