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HARDWARE ACTIvATION TESTS
Before starting, note total approximate bus cable length:
Once each cable has been checked with a LAN cable tes-
ter and plugged-in, it is still possible for the entire connect-
ed cable structure to become problematic . For instance,
dirt may accumulate inside the RJ45 sockets, the strain
on the Cat . 5 when pushing switches into the wall may
weaken connections or even break the conductors, or the
bus length may exceed 4000 ft .
Each test must be passed before moving onto the next . If
any readings are out of range, refer to "Hardware Activa-
tion Troubleshooting" section at the end of this document
or call Technical Support at 1-800-345-4448 .
CONTINUITY TEST
This test is intended to verify bus length, continuity, and
detect crossed data-pair wires .
1 .
De-power every item on the bus and check the volt-
age at both ends to ensure a reading of 0vdc . Re-
move any terminators .
2 .
At one end of the bus, plug in the "Data/Power Jumper . "
3 .
At the other end of the bus, plug in the "Bus Checker Card"
and measure resistance across the following terminals:
Gnd to A
____ohms B to +12
4 .
All test values must be within 10% of the values in the
chart below to be considered valid!
Continuity Test Results (Gnd to A & B to +12)
Length
Ohms
3 Ω to 6 Ω
100 ft .
12 Ω to 20 Ω 3000 ft .
500 ft .
34 Ω to 40 Ω 4000 ft .
1000 ft .
SHORT CIRCUIT TEST
This test is intended to detect any short circuits along the
bus . Please use the lowest resistance range (200 Ω) setting
on your multi-meter . DO NOT use a "beep" test .
5 .
Remove the "Data Power Jumper" and measure the
resistance across the following terminals on the "Bus
THE BLUE BOX LT SYSTEM START-UP & CABLING GUIDE
____ohms
Length
Ohms
68 Ω to 80 Ω
2000 ft .
102 Ω to 120 Ω
130 Ω to 160 Ω
Checker Card, "
6 .
All test values should be greater than 1K ohm!
Gnd to A
____ohms A to B
Gnd to B
____ohms A to +12
Gnd to +12
____ohms B to +12
EARTH GROUND TEST
This test is intended to detect any pathways to earth
ground .
7 .
Measure resistance between the terminals mentioned be-
low, and "Earth ground" (a metallic enclosure or conduit) .
Gnd
+12
8 .
All readings between each terminal and "Earth
ground" should be infinite or "Open"!
TERMINATOR TEST
This test is intended to ensure that only 2 terminators
exist, one at each end of the bus . If the readings are out of
range, it would indicate a missing, misplaced, or an extra
terminator (terminators are shipped in the Master Panel) .
9 .
Add a "Terminator" on the first and last device . On
the "Bus Checker Card", measure
A to B
10 .
Test reading should be within 62
11 .
Remove the bus checker card and call our Tech Sup-
port with your results at: 1-800-345-4448 x391 .
Figure A:
Bus Checker Card
____ohms
____ohms
____ohms
A
B
____ohms
Ω
to 92 Ω !
Data/Power Jumper
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