User manual

1-Wire Application Guide v1.04 Page 12 of 41
wiring. CAT-5 can be used for networks that are up to the maximum
recommended reach for 1-Wire: 300 feet or about 100 meters.
Use the Blue-White wire for DQ, and the White-Blue wire for Ground. Powering
can be done over any of the other pairs. Pick a pair and then stick to it for all of
your wiring to avoid mistakes in wiring later.
2.3.2 Connectors or Not?
Most 1-Wire sensors sold by all the vendors today come equipped with modular
connectors, either RJ-11, RJ-12 or RJ-45. Most sensors also come equipped
with some kind of screw-in connector as well, for terminating wires. The choice
of using a connectorized scheme for your network is yours and will be based on
several factors.
If you plan to relocate sensors a lot, then connectors are the way to go. If not,
then connectors may not make much sense. Using connectors implies that all
wiring is terminated with mating connectors. This may work for simple networks,
but may be too much trouble for larger, more complex networks.
If you do choose to use connectors, keep in mind that, while there is now a
standard for connector pin-outs, all vendors use slightly different variations for
pin-outs, simply due to the lack of standard when the sensors were first
developed, so be very careful when mixing different vendor’s sensors on a
network.
Here is a cross-reference table for some popular connector schemes.
Table 1 RJ-xx Connector Pin-outs
Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 Pin 7 Pin 8 RJ-45
Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 6 RJ-12
Device
Pin 1 Pin 2 Pin 3 Pin 4 RJ-11
Original Dallas
Weather Station
N/C DQ GND N/C
RJ-11
AAG RJ-11
Sensors/Interfaces
GND DQ GND +5VDC
RJ-11
Dallas/Maxim RJ-
12 wiring standard
(published Oct
2001)
+5VDC GND DQ GND N/C DC
Supply
RJ-12
Midon Design
MD2104
TEMP08/LOG08-
II/1WSwitch
DC
Supply
+5VDC DQ GND N/C N/C
RJ-12
Midon Design
Sensors
DC
Supply
+5VDC DQ GND N/C N/C
RJ-12
AAG RJ-12 +5VDC GND DQ GND N/C N/C
RJ-12