- 8 -
!
!
250 ft
3 4 5 8
13
300 ft
4 5 6
10
16
400 ft
5 6 8
13
21
500 ft
6 8
10
16
26
600 ft
8 10 12 19 31
800 ft
10 13 16 25 42
1000 ft
13 16 20 32 52
1250 ft
16 20 25 40 65
1500 ft
19 24 30 48 78
1750 ft
23 28 35 55 91
2000 ft
26 32 40 63
104
2500 ft
32 40 49 79
131
3000 ft
39 48 59 95
157
3500 ft
45 56 69
111
183
4000 ft
52 64 79
127
209
5000 ft
65 80 99
158
261
6000 ft
78 95
119
190
313
8000 ft
104 127 158 253 418
Unshielded Twisted-Pair Wire Gauge (AWG)
Cable
Distance
24
22
20
19
18
Unshielded Twisted-Pair Wire Gauge (AWG)
Distance
24
22
20
19
18
Unshielded Twisted-Pair Wire Gauge (mm)
Distance
0.5
0.6
0.7
0.8
1.0
3 4 5 8
13
4 5 6
10
17
5 7 8
13
21
6 8
10
16
26
9 10 13 21 34
13 16 19 31 51
17 21 26 42 69
21 26 32 52 86
26 31 39 62
103
32 39 49 78
129
38 47 58 94
154
43 52 65
104
171
51 63 78
125
206
64 78 97
156
257
77 94 117 187 309
102 125 156 249 411
Cable
Cable
75 m
100 m
125 m
150 m
200 m
300 m
400 m
500 m
600 m
750 m
900 m
1000 m
1200 m
1500 m
1800 m
2400 m
75 m
100 m
125 m
150 m
200 m
300 m
400 m
500 m
600 m
750 m
900 m
1000 m
1200 m
1500 m
1800 m
2400 m
3 5 6 9
13
4 7 9
12
18
6 8 11 15 22
7 10 13 18 27
9 13 17 24 36
13 20 26 36 54
18 27 35 48 72
22 33 43 60 90
26 40 52 72
108
33 50 65 89
135
40 60 78
107
162
44 66 86
119
179
53 80
104
143
215
66 100 130 179 269
79 120 155 215 323
106 159 207 286 431
Wiring Notes
Wire — What to
DO
1.
DO
use point-to-point Unshielded Twisted Pair wire, gauge 24 or
thicker, stranded or solid, Category 2, 3, 4, or 5.
2. The video signal may co-exist in the same wire bundle as other
video, telephone, data, control signals, or low-voltage power. It
is also OK to run NVT video signals in or near electromagnetic
fields (in accordance with National Electrical Code, local, or other
local safety requirements).
3.
DO
measure the wire distance. Use only transceivers that are
designed for that distance.
4.
DO
make sure the pair of wires carrying the video signal is sent
as a twisted pair (e.g. the blue-white/white-blue wires twisted
together as a pair), not a “split-pair” (e.g. blue-white conductor,
part of one pair/orange-white conductor, part of another pair).
Wire — What NOT to DO
1.
DO NOT USE SHIELDED TWISTED PAIR WIRE.
It will
severely degrade the distance performance. Short runs may be
used with some signal degradation (for example elevator traveler
cables). Multi-pair wire with an overall shield is OK.
2.
DO NOT USE UN-TWISTED WIRE.
It will reduce the NVT
product’s inherent interference immunity.
3.
DO NOT
allow your installation to have “bridge-taps”, loading
coils, talk-battery, or MOV type protectors. Bridge-taps are where
a twisted pair is connected to two twisted pairs (such as an
extension phone at home). Bridge-taps cause reflections as the
signal propagates, resulting in “ghosts” in the video image, and
are to be avoided.
4. If the phone company is providing the cable runs between
buildings, make sure it’s “dry copper” i.e. it should have none
of the following: dial-tone, 48 volts, loading coils, bridge-taps,
switching, or long paths to the phone company’s central office
and back.
5. Due to near-end crosstalk,
DO NOT
send a transmit and a
receive signal in the same wire bundle. Exceptions: Less than
1,000 ft (300m), or Category 5 cable, up to 2,000 ft (600m) are
OK.
6.
DO NOT
send “Up-the-Coax” Pan/Tilt/Zoom signals through
active (amplified) NVT transceivers.
Measure your wire distance
Note: All NVT quoted distance specifications include any coax in the
run. It is recommended that the wire distance be measured to ensure
that the capability of the NVT product is correct.
Wire resistance may be measured with an ohm-meter by shorting
the two conductors together at the far end, and measuring the loop-
resistance out and back. Compare your readings with the charts in
the next column.
7. For safety, never put NVT signals in the same conduit as
high-voltage wiring.
8.
WARNING
— to reduce a risk of fire or electrical shock, do
not expose this product to rain or moisture.
