nVent RAYCHEM RMM2-E Installationsanleitung Seite 6

6. Connect lead wires from each RTD to the selected RMM2-E
EN
terminal block
DE
The RMM2-E has 8 terminal blocks to connect lead wires
from 8 RTDs. Each RTD connection is numbered; the number
FR
identifies the RTD, and determines the order in which the NGC
system displays the RTD measurement. Therefore, order the RTD
RU
connections in a manner that makes the NGC system display
most meaningful.
The RMM2-E cover shows the correct wiring arrangement for the
RTD wires. With nVent RAYCHEM RTDs, connect the two RTD lead
wires of the same colour to the terminals marked "-" and connect
the RTD lead wire that is a different colour to the + terminal.
RMM2-E terminal no.
1
2
3
4
5
6
7
8
D. Select RS-485 Address and Connect the RS-485 Bus Cables
9. Select the RS-485 address for the RMM2-E unit.
Each RMM2-E connected to a NGC control and monitoring system
must have a unique address; if two RMM2-E's are assigned
the same address, communication faults will result. To ensure
that you assign a unique address to each RMM2-E unit, do the
following:
• Review the NGC system layout; if a layout document does not
exist, create one. If it has not already been done, assign an
RS-485 address to each RMM2-E (up to 16) connected to the
NGC system.
• If you are adding one or more RMM2-E units to an existing
NGC network, confirm that the RS-485 addresses for existing
RMM2-E units correspond to the system layout. See for details
the programming guide of the NGC system.
By checking the RS-485 addresses on an existing system, you
can avoid potential conflicts that would be confusing and time
consuming to troubleshoot otherwise.
Record the RS-485 address selected for the Remote Monitoring
Module you are currently installing, and label the exterior of
the enclosure with the address assigned to the RMM2-E. For
reference, here are the 16 possible RS-485 addresses: (0 -15
HEXADECIMAL)
0 1 2
8 9 A
10. Set the RS-485 address for the RMM2-E unit using the rotary
switch provided
Take of the lid and use a flat-blade screwdriver to rotate the RS-
485 address switch to the desired position. The single character
visible on the switch indicates the RS-485 address assigned.
0
|
6 nVent.com/RAYCHEM
Piping drawing identification
3 4 5 6
B C D E
7
0
6
7. If RTD-shield is not earthed elsewhere, connect shield to
earth terminal.
8. Record the location/identification for each RTD.
Because the RMM2-E terminal connection number identifies the
RTD in the NGC system, it is important to record the location of
each RTD. Use the space below to record the connections, and
label the RMM2-E or its enclosure with this RTD identification
information.
11. Connect the RS-485 bus
Note: Do not make connections to the RS-485 bus while it is
connected to an operating NGC network. Damage and/or alarms
could result.
The RS-485 bus allows units with unique addresses to be
connected together along a common bus. To add a new unit to
the network, simply connect 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 RMM2-E must be assigned a unique address
The RS-485 bus must be a continuous string from the first
network device to the last RMM2-E 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.
7
F
Description or location