TimeLink TLR401, Руководство пользователя

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TLR401 Administration
27
8.3 Wiring Requirements
Notice:
Do not install data cabling parallel to high voltage cables. If unavoidable install data cabling in
conduit and keep a distance of 3 ft. to protect from electromagnetic interference.
RS485
Shielded twisted pair cable (4000 feet max) e.g.:
1. 2x2 strands litz wire AWG24 (0.4 kcmil)
2. J-Y(ST)Y 2x2x0,6
3. CAT 5 ... 7 STP (Shielded Twisted Pair)
Wiegand
Non-twisted shielded cable (500 feet max) e.g.:
1. 10 pair shielded wire AWG22 (0.64 kcmil)
For shorter distances or using higher supply voltage:
2. 8 pair AWG24 (0.4 kcmil)
Consider whether or not to supply power with the data cable. Long distances require an increased
gauge of cable. Supplying power locally or having an extra power cable pull may be preferable.
Because of voltage drop over longer distances use of a 24V power source is the recommended
choice.
Example for calculating the power supply wiring:
1. AWG22 cable (0,34 mm
2
):
Loop resistance ca 115 ohm / km
TLR401 current with 12V = 0,2A
Cable length 150m
Voltage drop: 115 ohm / km * 0.15km * 0,2A = 3.45V
The supply voltage should be 15V in this case
2. AWG24 cable (0,25 mm
2
):
Loop resistance ca 180 ohm / km
TLR401 current with 12V = 0,2A
Cable length 150m
Voltage drop: 180 ohm / km * 0.15km * 0,2A = 5,4V
The supply voltage should be 18V in this case