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THERMAL MANAGEMENT SOLUTIONS
EN-TraceTekTTNRM-IM-H57474 01/13
D. connect RS-485 cables and set address
1. Select the RS-485 address for the TT-NRM unit.
Each TT-NRM connected to a TTDM-128 must have a unique
address in the range 1 to 99. If two TT-NRM units are as-
signed the same address, communications faults will result.
To ensure you assign an unique address to each TT-NRM unit,
review the system layout. If a layout document does not exist,
create one. Assign an unique address to each TT-NRM unit.
Note: TraceTek TTSIM modules are connected on the same
RS-485 network and must not have the same address as any
TT-NRM.
2. Set the RS-485 address for the TT-NRM unit.
Use a small flat-blade screwdriver to rotate the address
switch marked “x1” to the desired address. For an address
of 50, set the “x1” to 0 and the “x10” to 5.
Set address 0-9
Set 10's digit of address
L
N
+
–
ON
TxD
IO/RN
IO/ER
RxD
CRC
Address x 1
x 10
WAGO 750-315
I/0
SYSTEM
24V 0V
750-517 750-517 750-517
RS-485
3
2
1
Note: Previous wiring omitted for clarity
POWER SUPPLY
3. connect RS-485 cables.
Note: Do not make connections to the RS-485 bus while it
is connected to an operating TTDM-128, or damage and/or
alarms could result.
The RS-485 bus allows units with unique addresses to be
daisy-chained together along a common bus. To add a new
unit to the network, simply daisy-chain the RS-485 bus from
the last unit to the new one—or insert the new unit between
two existing units on the bus. The order in which units are
attached to the RS-485 bus does not matter. There are just
two constraints on the RS-485 network:
• Each TT-NRM must be assigned a unique address.
• The RS-485 bus must be a continuous string from the
first unit to the last unit in the system.
Note: The RS-485 bus operates at 5 V, and equipment
connected to it could be damaged by exposure to higher
voltages. Take precautions to avoid exposing the RS-485
wiring to discharge of static electricity or other sources of
high voltage potential; in particular, avoid contact with the
power supply wiring.
4
3
2
1
Connect the clear or white wire of the RS-485 cable to
the (+) terminal as shown.
4
3
2
1
Connect the black wire of the RS-485 cable to the (–)
terminal as shown.
4
3
2
1
Connect the shield wire of the RS-485 cable to the
shield terminal as shown.
If connecting two RS-485 cables (one IN and one OUT), use
the same terminals for both wires.
Important: Do not connect the shield of the RS-485 cable
to the enclosure or panel grounding terminal. Connect the
shield only to the terminal provided. To avoid the potential
for spurious ground loops, the RS-485 cable shield should
be connected to ground only in the TTDM-128.
