Lighting Controls Blue Box LT Series Installation, Operation & Maintenance Manual page 42

42
HARDWARE ACTIvATION TESTS
Before starting, note total approximate bus cable length:
Once each cable has been checked with a LAN cable
tester and plugged-in, it is still possible for the entire con-
nected cable structure to be problematic . For instance,
dirt may have accumulated 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 voltage
at both ends to ensure a reading of 0vdc . Remove 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
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 multimeter . DO NOT use a "beep" test .
5 . Remove the "Data Power Jumper . " On the "Bus Checker
Card, " measure the resistance across the following terminals:
THE BLUE BOX LT ADDING A NEW DEVICE
B to +12 ____ohms
Length Ohms
68 Ω to 80 Ω
2000 ft
102 Ω to 120 Ω
130 Ω to 160 Ω
6 . All test values should be greater than 1K ohm!
Gnd to A ____ohms
Gnd to B ____ohms
Gnd to +12 ____ohms
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 .
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 Ω to 92 Ω !
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
A to B ____ohms
A to +12 ____ohms
B to +12 ____ohms
A
B
____ohms
Data/Power Jumper