Crestron CP3, Руководство по эксплуатации

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Crestron CP3 & CP3N 3-Series Control Systems
Operations Guide – DOC. 7316C 3-Series Control Systems: CP3 & CP3N • 25
chained must be added together to determine the Cresnet power usage of the entire
chain. If the unit is run from a Crestron system power supply network port, the
Cresnet power usage of that unit is the Cresnet power usage of the entire run. The
wire gauge and the Cresnet power usage of the run should be used in the following
equation to calculate the cable length value on the equation’s left side.
Cable Length Equation
L = Length of run (or chain) in feet
R = 6 Ohms (Crestron Certified Wire: 18 AWG (0.75 mm ))
or 1.6 Ohms (Cresnet HP: 12 AWG (4 mm ))
P = Cresnet power usage of entire run (or chain)
2
2
L < 40,000
R x P
Where:
Make sure the cable length value is less than the value calculated on the right side of
the equation. For example, a Cresnet run using 18 AWG Crestron Certified Wire and
drawing 20 watts should not have a length of run more than 333 feet (101 meters). If
Cresnet HP is used for the same run, its length could extend to 1250 feet (381
meters).
NOTE: All Crestron certified Cresnet wiring must consist of two twisted pairs. One
twisted pair is the +24V conductor and the GND conductor and the other twisted
pair is the Y conductor and the Z conductor.
Strip and Tin Wire When daisy chaining Cresnet units, strip the ends of the wires carefully to avoid
nicking the conductors. Twist together the ends of the wires that share a pin on the
network connector and tin the twisted connection. Apply solder only to the ends of
the twisted wires. Avoid tinning too far up the wires or the end becomes brittle.
Insert the tinned connection into the Cresnet connector and tighten the retaining
screw. Repeat the procedure for the other three conductors.
Add Hubs
Use of a Cresnet Hub/Repeater (CNXHUB) is advised whenever the number of
Cresnet devices on a network exceeds 20 or when the combined total length of
Cresnet cable exceeds 3000 feet (914 meters).
Reference Documents
The latest version of all documents mentioned within the guide can be obtained from
the Crestron Web site ( www.crestron.com/manuals ).
List of Related Reference Documents
DOCUMENT TITLE
3-Series Control Systems Reference Guide
Crestron e-Control Reference Guide
Further Inquiries
To locate specific information or resolve questions after reviewing this guide,
contact Crestron's True Blue Support at 1-888-CRESTRON [1-888-273-7876] or
refer to the listing of Crestron worldwide offices on the Crestron Web site
( www.crestron.com/offices ) for assistance within a particular geographic region.
To post a question about Crestron products, log onto the Online Help section of the
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