Det-Tronics Eagle Quantum 95-8470-05, Инструкция по эксплуатации

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A combustible gas DCU draws approximately 500 mA
at startup, therefore, the total current load is 5 amps.
(10 units x 500 mA = 5 amps)
Refer to the 5 Amp Load column in the table. Since the
maximum allowable voltage drop is 6 volts, 16 AWG (or
larger) wire is required.
IMPORTANT
To ensure proper operation of field devices, the
voltage input to the device (measured at the
device) must be within the range indicated for that
device in the “Specifications” section of this
manual.
NETWORK WIRING
All devices on the LON/SLC are wired in a loop that
starts and ends at the LCU. To ensure proper
operation, the LON/SLC should be wired using high
speed communication grade cable. Cable meeting the
specifications listed in Table VI-2 is suitable for
distances up to 2000 meters. Any of the cable types
listed in Table VI-3 can be used for wiring the LON/SLC
for the distances indicated. If no network extenders are
used, the distances listed are for the entire loop. If
network extenders are used, the distances listed are for
the wiring length between network extenders or
between a network extender and the LCU. The use of
other cable types can degrade system operation. For
optimum fault isolation performance, the maximum
LON/SLC wiring length should not exceed 1600 feet
(500 meters).
SHIELD GROUNDING
Two shield ground terminals are provided inside the
junction box of each field device and also at the LCU.
Connect the shield ends to the terminals provided (not
to each other) inside the junction box.
CAUTION
Insulate the shields to prevent shorting to the
device housing or to any other conductor.
VI-2
Table VI–3—Communication Loop Wiring Cable
Minimum Typical Maximum Units Condition
DC Resistance, each conductor 14 14.7 15.5 ohm/km 20 C per ASTM D 4566
DC Resistance Unbalanced 5% 20 C per ASTM D 4566
Mutual Capacitance 55.9 nF/km per ASTM D 4566
Characteristic Impedance 92 100 108 ohm 64 kHz to 1 MHz, per ASTM D 4566
Attenuation 20 kHz 1.3 dB/km 20 C per ASTM D 4566
64 kHz 1.9
78 kHz 2.2
156 kHz 3
256 kHz 4.8
512 kHz 8.1
772 kHz 11.3
1000 kHz 13.7
Propagation Delay 5.6 nsec/m 78 kHz
Length: 6,500 feet/2000 meters maximum (basic loop or between Network Extenders).
Type: Single twisted pair.
Wire Gauge: 16 AWG, stranded (19 x 29), tinned copper with overall shield.
Cables meeting these specifications are good for up to 2000 meters.
T0049B
Table VI-2—Specifications for LON Wiring Cable
Cable Type Maximum Length
Feet Meters
Belden 8719 6500 2000
Belden 85231 6500 2000
Level IV, 22 AWG 4500 1370
JY (St) 2x2x0.8 3000 900
Be sure that selected cable meets all job specifications.
If necessary, consult factory for further suggested cable types.