Videolarm qmrt2-50na Guia Do Utilizador

- 5 -

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 �

Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω

Unshielded Twisted-Pair Wire Gauge (AWG)�

Cable�

Distance�

Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω

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 �

Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω

Cable�

Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω

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 �

2. Connect the other end of the unshielded twisted pair cable to the
NVT receiver.

CAUTION: The unshielded twisted pair video signal is polarity

dependent. The positive video wire for each camera
MUST be connnected to the postitive terminal on the
NVT receiver, and negative MUST be connected to
negative.
3. When using unshielded twisted pair cable you DO NOT need the
BNC connector. All four BNC connectors are provided inside the
housing for testing purposes. Be sure that there is no video con-
nection other than the unshielded twisted pair cable.

Wiring Notes

Wire — What to

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).

DO measure the wire distance. Use only transceivers that are

designed for that distance.

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

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.

DO NOT USE UN-TWISTED WIRE. It will reduce the NVT

product’s inherent interference immunity.

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.

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
below.

7. For safety, never put NVT signals in the same conduit as

high-voltage wiring.

WARNING — to reduce a risk of fire or electrical shock, do

not expose this product to rain or moisture.