Wybron 87250, Руководство пользователя

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The HEAD-FEET parameter is a method of accounting for the voltage drop in the
power/signal cable caused by the current drawn by each dowser.
To help understand this issue, think of it as water pressure (voltage) in a hose (cable)
feeding multiple water sprinkler heads (dowsers). If the hose (cable) is too long, or too
many sprinkler heads (dowsers) draw from the hose, the water pressure (voltage) will be
too low.
HEAD-FEET is defined as "the sum of cable lengths from each dowser to a single power
supply output.”
Head-Feet Example
Consider this example: Three Eclipse IT Iris units are connected to a power supply. The 4-
pin power/data cable between the power supply and the first Eclipse Iris IT is 100 feet long.
The cable between the first and the second Eclipse is 20 feet long, and the cable between
the second and third Eclipse is also 20 feet long.
The amount of cable from the power supply to:
1st Eclipse IT Iris 100 ft
2nd Eclipse IT Iris 120 ft
3rd Eclipse IT Iris 140 ft
Total:
360 "head-feet"
Head-Feet Limits
•
1K (7.5”) Eclipse IT Iris (Model 87250): 1,500 head-feet
•
10” Eclipse IT Iris (Model 810060): 1,500 head-feet
•
2K (12”) Eclipse IT Iris (Model 812020): 1,500 head-feet
•
24” Eclipse IT Iris (Model 823020): 750 head-feet
If a daisy chain includes different models, use the model with the smallest amount of
"head-feet" for the calculation.
Equipment Compatibility/Power Supply Capacity
This chart shows the capacity and compatibility for the various models of PS Power Supply
units and their companion devices.