Guppy PRO Technical Manual
V4.1.2
31
FireWire hot-plug and screw-lock precautions
Caution
Hot-plug precautions
•
Although FireWire devices can theoretically be hot-
plugged without powering down equipment, we strongly
recommend turning off the computer power, before
connecting a digital camera to it.
•
Static electricity or slight plug misalignment during
insertion may short-circuit and damage components.
•
The physical ports may be damaged by excessive
electrostatic discharge (ESD), when connected under
powered conditions. It is good practice to ensure proper
grounding of computer case and camera case to the
same ground potential, before plugging the camera cable
into the port of the computer. This ensures that no
excessive difference of electrical potential exists between
computer and camera.
•
As mentioned earlier, it is very important not to exceed
the inrush energy of 18 mWs in 3 ms. (This means that a
device, when powered via 12 V bus power, must never
draw more than 1.5 A, especially in the first 3 ms.)
•
Higher inrush current may damage the physical interface
chip of the camera and/or the PHY chip in your PC.
For a single Guppy PRO camera inrush current may not be
a problem. But daisy chaining multiple cameras or
supplying bus power via (optional) Hirose power out to
circuitry with unknown inrush currents needs careful
design considerations.
Screw-lock precautions
•
All Allied Vision IEEE1394b camera and cables have
industrial screw-lock fasteners to insure a tight electrical
connection that is resistant to vibration and gravity.
•
We strongly recommend using only IEEE1394b adapter
cards with screw-locks.
