nvent Raychem RMM2 Installation Instructions Manual

RMM2

WARNING:

Heat-Tracing Remote Monitoring Module for the nVent RAYCHEM NGC Control System
Installation Instructions

(RMM2-4X shown)

TOOLS REQUIRED

• 3 mm slotted screwdriver • Needle nose pliers

• 3/8 hex key (for RMM2-4X only) • Wire stripper/cutter

APPROVALS

Nonhazardous locations

Type NM

80BJ ENERGY MANAGEMENT

EQUIPMENT SUBASSEMBLY AND

Hazardous locations

KIT CONTENTS

LISTED

GENERAL SIGNALING

EQUIPMENT SUBASSEMBLY

LISTED

9Z63 TEMPERATURE
INDICATING EQUIPMENT
FOR USE IN HAZARDOUS

LOCATIONS

RMM2-4X (RMM2 with Type 4X Enclosure)

Class I, Division 2, Groups A, B, C, D
Class II, Division 2, Groups F, G

DESCRIPTION

The nVent RAYCHEM remote monitoring module (catalog no.
RMM2) is part of the RAYCHEM NGC Control System. The
RMM2 takes inputs from up to 8 RTDs that measure pipe, vessel,
or ambient temperatures in a heat-tracing system. Multiple
RMM2 units communicate with a RAYCHEM NGC controller
using a single RS-485 bus (a shielded, twisted pair).

Refer to the specific RAYCHEM NGC controller Installation and
Operation manual for additional information. For technical
support call nVent at [phone].

MONITORING SYSTEM COMPONENTS AND ACCESSORIES

RMM2 RMM2 module without enclosure (for use with user-

RMM2-4X Reinforced polyester Type 4X enclosure with RMM2,

Additional Materials Required

User supplied
enclosure

RTDs For measuring temperatures. Make RTD selection

Extension wire

MONI-RTD-WIRE Shielded cable with three 22 AWG wires;

MONI-RS485­WIRE

Conduit drain

JB-DRAIN-PLUG­3/4IN

supplied enclosures.)

grounding hardware and four plugs. For Ordinary and
Division 2 hazardous locations.

Agency-approved enclosure fitted with an aluminum
DIN 35 rail and grounding hardware. For Ordinary and
Division 2 hazardous locations only.

based on temperature range of heat-tracing
application. Up to eight three-wire RTDs may be used.

PVC insulation; for use as RTD lead wire. 1000 ft reel.
Shielded cable with twisted pair of 22 AWG wires;
PVC insulation; for use as RS-485 bus. 1000 ft reel.

PN 278621 (recommended for Division 2 locations)

Item Qty Description

A 1 RMM2 module

B 2 Spare fuses - 200 mA 250 V

C 2

Jumpers (Use 2 jumpers for 115 V or 1 jumper for 230 V)

D 1 Product label (for user supplied enclosures only)

1 Enclosure - not shown (for RMM2-4X only)

This component is an electrical device that
must be installed correctly to ensure proper
operation and to prevent shock or fire. Read
these important warnings and carefully follow
all of the installation instructions.

A

• Component approvals and performance are
based on the use of nVent -specified parts
only. Do not use substitute parts.

• Keep components dry before and during
installation.

B

C

D

• NOTE: Leave these instructions with the end
user for reference and future use.

RAYCHEM NGC SYSTEM LAYOUT

Typical example of individual control with NGC-30-CRM and
RMM2 modules for ground-fault trip/monitoring and
temperature/heating-cable current monitoring. RMM2 remote
monitoring modules collect RTD inputs and communicate with
the NGC controller using a single RS-485 bus.

NGC-30-CRM/CRMSNGC-30-CRM/CRMS

RTD

RS-485

Pipe

RMM2 Remote

Monitoring Module

NGC-UIT2

C

7

1

8

2

3

4

5

6

C

9

10

11

12

NGC-30-CTM

Panel board

NGC-30
Control Panel

RAYCHEM REMOTE MONITORING MODULE (RMM2)

1 Fuse 200 mA 250V (two spare fuses are supplied with the

RMM2)
2 Terminals for power input with provision for daisy-chaining
3 Voltage selector jumpers: Use one for 230V applications

(default); use two for 115V applications (see Step 7 on

page4).

4 Terminals for RS-485 bus with provision for daisy-chaining
5 Shorting block to select RS-485 termination mode for last

RMM2 module in network
6 LEDs which indicate communications activity

7 Rotary switch (16 position) to assign RS-485 address

8 LED which indicates power to the RMM2
9 Terminals for RTD lead wires

10 Orange slotted tab
11 Clear plastic cover

Heating
cable

RTD

Pipe

RMM2 Remote

Monitoring Module

Heating
cable

Note: Use a small slotted screwdriver to pry clear plastic cover
off the RMM2 module. When replacing cover make sure “RTD1”
on the clear cover is aligned with “RTD1” on the RMM2 module.
Press firmly on cover until it is fully engaged.

Raychem

Raychem

Raychem

2 | nVent.com

A qualified electrician should install the RMM2 following these installation instructions.

A. MOUNT RMM2 IN AN ENCLOSURE SELECTED FOR THE APPLICATION

1. Selectanelectricalenclosuresuitablefortheuse

environment.

The RMM2 attaches to a DIN 35 rail in an electrical enclosure.
User supplied enclosures must have grounding terminals.

The RMM2 is powered with line voltage in appropriate enclosure.
To select the enclosure, consider the area classification

(e.g.non-hazardous or Division 2 hazardous area), the location

(indoors or outdoors; exposure to moisture and/or dust) and the
chemical environment.

• To meet the requirements for Division 2 locations and

typical industrial environments, nVent offers the RMM2 with
a fiberglass reinforced polyester enclosure rated Type 4X
(catalog number RMM2-4X).

Use agency-approved glands and fittings to maintain Type rating
of enclosure.

The enclosure noted in the previous paragraph is configured
specifically for the RMM2. If a different enclosure is used for
Division 2 locations and typical Industrial environments, it must
be fitted with the following hardware to mount the RMM2:

• DIN 35 rail to which to attach the RMM2. The rail should fit the

enclosure and be at least 6-1/2 in. (180 mm) long.

• Grounding hardware.

• Rail end stops to hold the RMM2 in position may be needed.
Mounting this hardware on a separate panel (which attaches to

the enclosure) may simplify the configuration.
Note: The operating temperature range of the RMM2 is –40°F

to 140°F (–40°C to 60°C). If the enclosure is mounted in an area
that may drop below –40°, it should be fitted with a suitable
space heater.

2. Drillorpunchentriesintotheenclosurebeforemounting

theRMM2.

The RMM2 is an electronic device that could be damaged by
filings or other debris. The RMM2-4X comes supplied with
six 3/4 inch conduit entries for installation of power wiring,
RS-485 cables, and RTDs. The enclosure will need entries for the
following connections:

• Each RTD to be connected (up to 8)

• RS-485 bus (incoming and outgoing)

• Power and ground wiring (incoming and outgoing)
To help determine the best entry arrangement, see the

illustration on page 2, which shows the terminal arrangement
on the RMM2. Typically, power wiring is run in one entry,

RS-485cables in another entry, and RTDs in the remaining
4entries.

Note: To prevent water ingress, use conduit drains if applicable
and do not make conduit entries in the top of the enclosure.

3. Mounttheelectricalenclosure.

Mount the enclosure so that the RMM2 will not be exposed to
abuse or damage.

• Do not attach the enclosure to pipes or equipment that could
subject the unit to continued vibration.

• Important: Do not locate the enclosure where the RMM2 could
be subjected to temperatures inside the enclosure of greater than
140°F (60°C) (e.g. directly exposed to sunlight in hot climates).

• Use mounting hardware suitable for the Type rating of the
enclosure.

• Apply the RMM2 product label onto the cover of user supplied
enclosures.

4. AttachtheRMM2totheDIN35rail.

Position the RMM2 with RTD connections on the same side as
conduit entry holes in enclosure.

• Slip the green tabs on the underside of the RMM2 under one
side of the DIN 35 rail. Pivot the RMM2 towards the DIN rail
until the orange tab makes contact with the rail. Press the
RMM2 towards the rail until the orange tab (

therail. Do not use excessive force.

• To remove the RMM2 from the DIN rail, slip a small slotted
screwdriver into the rectangular slot in the orange tab, push
the tab away from the DIN rail, and pivot the RMM2 away from
the rail.

(RMM2-4X shown)

10

) snaps over

nVent.com | 3

B. CONNECT POWER AND GROUND WIRING AND SELECT VOLTAGE OPERATING RANGE

WARNING: Shock Hazard. Shut off power to power

cablebeforeproceeding.

Note: For hazardous area installations, input and output (I/O)
wiring and conduit seals must be installed in accordance with
applicable Division 2 requirements.

5. Connectwiringfromthepowersourcetodesignated

terminals on RMM2

Use only copper conductors.
Connect power wires to the
terminals marked L1 and L2
on the RMM2. If power is
being daisy chained, be sure

Raychem

Raychem

Raychem

to maintain polarity of L1
and L2 wiring for incoming
and outgoing wires. Connect
the ground wire(s) to the
grounding terminals mounted
on the DIN rail.

The terminals can accept wires from 24 to 12 AWG. We
recommend 12 AWG flexible stranded wire with branch circuit
protection sized accordingly. Cable should have a minimum
temperature rating of 149°F (65°C).

6. Connectgroundwiring.

Use only copper
conductors. Connect
ground wires to
ground terminals in
the enclosure.

Note: If a ground wire
is part of the power
cable, it must be
longer than the other
two conductors for
strain relief.

The RMM2-4X uses spring clamp terminals. These terminals
have a steel spring that clamps the wire to a copper bus bar.
This provides improved vibration resistance, reduced
maintenance and faster installation.

To connect wires, firmly insert a flat-blade

A

screwdriver (

) into the square hole to

open the spring. When fully inserted, the

A

B

screwdriver will lock into place, allowing
you to remove your hand and insert the

wire into the round hole(

). Remove the

Wire

screwdriver to clamp the wire. The wire
is held securely against the bus bar for
low contact resistance over time without
the need to periodically retighten screws.

7. Selectthevoltageoperatingrange

Screwdriver slot

Wire hole

Connect the supplied
jumpers to the appropriate

3

terminals (

) to select

input voltage. The RMM2

Raychem

comes supplied jumpered

Raychem

Raychem

for 230 volts.
The RMM2 has terminals

for 8 three-wire, 100 Ω

platinum RTDs; do not
use other types of RTDs.
Select RTDs appropriate
for the usage and

Jumpered for

230V (default)

Jumpered

for 115V

temperature requirements.

C. CONNECT RTD WIRES TO THE RMM2

Install each RTD in accordance with the installation instructions
shipped with it, and run the RTD lead wires to the RMM2.

Note: Each of the three lead wires from each RTD must have a

resistance of 20 Ω or less.

8. ConnectleadwiresfromeachRTDtotheselectedRMM2

terminals

The RMM2
accepts up to

8RTDs. Each

RTD connection
is numbered; the
number identifies
the RTD, and
determines
the order in
which the
NGC controller
displays the RTD

4 | nVent.com

Note: If the RTD lead wires are reversed,
the NGC controller will report an incorrect
temperature measurement or an RTD error.

Install per Raychem RMM2 Instruction Manual. (For North America use ref. H56848.)
Raychem Montage - und Betriebsanleitung beachten
Suivre attentivement les instructions d’installation de Raychem

measurement. Therefore, order and group the RTD connections
in a manner that makes the NGC controller display most
meaningful.

The RMM2 cover shows the correct wiring arrangement for
the RTD wires. Connect the two RTD lead wires of the same

color tothe terminals marked “-” (on the right in the illustration

below); connect the RTD lead wire that is a different color to

the“+”terminal.

If RTD shields are not grounded elsewhere, connect shield to
ground terminal in enclosure.

9. Recordthelocation/identificationforeachRTD

Because the RMM2 terminal connection number identifies
the RTD in the RAYCHEM NGC control system, it is important
to record the location of each RTD. Use the table on page 7 to
record the connections, and label the RMM2 or its enclosure
with this RTD identification information.

D.SELECTRS-485ADDRESSANDCONNECTTHERS-485BUS

Device must be mounted in series.

10. SelecttheRS-485addressfortheRMM2

Each RMM2 connected to an NGC controller must have a
unique address; if two RMM2s are assigned the same address,
communication faults will result. To ensure that you assign a
unique address to each RMM2, 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 (up to 16) connected to the
NGC controller. Record the RS-485 address assignments and
save for future reference.

• If you are adding one or more RMM2 to an existing NGC system
network, confirm that the RS-485 addresses for existing
RMM2s correspond to the system layout. You can do so by
observing the NGC controller display. When the NGC controller
displays a temperature it identifies the RTD with a two-part tag;
the prefix indicates the RMM2 address, and the suffix indicates
the terminal number to which the RTD is connected. For example,
RTD 33-7 identifies an RTD connected to the RMM2 with

RS-485address 33, RTD terminal 7.

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 RMM2 you are
currently installing, and label the exterior of the enclosure with the
address assigned to the RMM2.

11. SettheRS-485addressfortheRMM2usingtherotary

switch provided

Note the orientation
of the clear plastic

11

cover, (
remove the cover.

Use a slotted
screwdriver to rotate
the selector switches
to the appropriate
positions to select the
RS-485 address.

The single character
visible on the switch
indicates the RS-485
address assigned.

12. ConnecttheRS-485bus

Note: Do not make connections to the RS-485 bus while it is
connected to an operating NGC controller, or damage and/or
alarms could result.

The RS-485 bus allows units with unique addresses to be daisy­chained 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:

) then

Raychem

Raychem

Raychem

RMM2 Switch Settings

Switch
Settings

Device
Address

Switch
Settings

Device
Address

0 1 2 3 4 5 6 7 8 9

32 33 34 35 36 37 38 39 40 41

A B C D E F

42 43 44 45 46 47

• Each RMM2 must be assigned a unique address.

• The RS-485 bus must be a continuous string from the

NGCcontroller to the last RMM2 in the system.

Note: The RS-485 bus operates at 5V, 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.

TypicalexampleofRS-485busconnectionforthe
NGC-30 control system

The RMM2 has two
sets of terminals
for connections to
the RS-485 bus.
One terminal block

(Terminated devices are shown in gray)

RMM2

0

allows the RMM2
to connect to the
RS-485 bus, the
second allows a
continuation of the
bus to other RMM2s
on the network.

NGC-UIT

PLI

HN/H G A B C N

NGC-UIT

6

0

S2 S1

6

0-9

110
.

220
.

S

+

S +

36

S

Norm

Mixed

Observe polarity,
which is indicated on
the RMM2 cover.

Connect the
incoming RS-485
bus to the set of
terminals marked
“IN”, observing the
polarity noted on the
cover of the RMM2;
use the terminal
marked “S” for the
shield of the RS-485
cable. Connect the
continuation of the
RS-485 bus to the

NGC-CRM/-CRMS

MSB LSB

TB 1 TB 2 TB 3 TB 4 TB 5

1 2 3

TB 19

TB 12

TB 7 TB 6

TB 13 TB 14 TB 15 TB 16 TB 17

NGC-CRM/-CRMS

MSB LSB

TB 1 TB 2 TB 3 TB 4 TB 5

1 2 3

TB 19

TB 12

TB 7 TB 6

TB 13 TB 14 TB 15 TB 16 TB 17

PLI

HN/H G A B C N

RMM2

6

S2 S1

6

110

.

220
.

S

+

S

Norm

Mixed

Jumper

0

0

0-9

S +

36

NGC-CRM/-CRMS

MSB LSB

TB 1 TB 2 TB 3 TB 4 TB 5

1 2 3

TB 19

TB 12

TB 7 TB 6

TB 13 TB 14 TB 15 TB 16 TB 17

NGC-CRM/-CRMS

MSB LSB

TB 1 TB 2 TB 3 TB 4 TB 5

1 2 3

TB 19

TB 12

TB 7 TB 6

TB 13 TB 14 TB 15 TB 16 TB 17

NGC-CRM/-CRMS

MSB LSB

TB 1 TB 2 TB 3 TB 4 TB 5

1 2 3

TB 19

TB 12

TB 7 TB 6

TB 13 TB 14 TB 15 TB 16 TB 17

set of terminals
marked “OUT” in the
same manner (not required for the last RMM2 in the network).

Important: Do not connect the shield of the RS-485 cables to the
enclosure’s grounding terminal. Connect the shield only to the
RMM2 terminals provided. To avoid the potential for spurious
ground loops, the RS-485 cable shield should be connected to
ground only in the NGC controller.

For the last RMM2 in
the network, terminate
the RS-485 bus by
removing the shorting
block on jumper
location J17 from 2–3
and placing it across
pins 1–2.

Replace the clear

11

plastic cover (

) in its

original orientation.

Raychem

Raychem

Raychem

Default position
(for all RMM2
units in network
except last one)

J17

1 2 3

Last RMM2
in network

Termination mode
(last RMM2 in network)

J17

1 2 3

nVent.com | 5

E. INITIALIZE OR UPDATE THE NGC SYSTEM NETWORK AND ASSIGN SETTINGS FOR EACH RTD

RMM2 units are monitored by a central NGC controller. Its
system software enables you to trigger the NGC controller to

recognize changes to the RMM2 and RTD  configuration. Until

this software is run, the NGC controller will not monitor new
RMM2s or RTDs.

13. EnergizeallRMM2sinthenetwork

Confirm that the RS-485 network is complete (all RMM2 units
and the NGC controller are connected to the RS-485 bus), and
that the power to each unit has been turned on.

14. UsetheNGCcontrolsystemsoftwaretoinitializeorupdate

the network

Run the NGC control system software function to trigger it to
recognize new RMM2s and RTDs. Use the “Update Network”
function for first time setup, additions, or changes to a system.
For example, the NGC-30 Programming Guide (H58186)
describes these software functions in Section 3.1 “Setting the
Network for Device(s)”.

15. Ifnecessaryduetoproblemsorquestions,checkfunction

of individual RMM2 modules

• Check all connections.

3

• Verify that the voltage selector jumpers (

) are installed for the

appropriate range (see Step 7 on Page 4).

• Verify that each RMM2 is functioning by confirming that the

8

RUN LED (
RCV LEDs (

) is illuminated and the communications XMT and

6

) are flashing.

• Confirm that the RMM2 network does not have any duplicate
RS-485 addresses.

• Check the fuse. If the resistance is greater than 10Ω, replace.

16. UsetheNGCcontrolsystemsoftwaretoassignsettingsfor

each RTD

Run the NGC control system software function to assign
settings for each RTD:

• RTD mode (determining whether it is in Control or Monitoring
mode).

• Low and high temperature alarms (if desired, alarms can be
set independently for each RTD, separately from the thresholds
assigned for the control group overall).

For example, the NGC-30 Programming Guide (H58186)
describes these software functions in Section 3.3.5
“SETUP|RTDS WINDOW”.

F. FUSE REPLACEMENT

1

• Important: Disconnect power before replacing a fuse.

11

• Pry off the clear plastic cover (

) using a small slotted

screwdriver.

• Use needle nose pliers to remove the fuse marked F200 mA 250V.

• Install a replacement fuse (supplied with the RMM2).

11

• Align “RTD1” on the clear plastic cover (

) with “RTD1” on the

RMM2. Press firmly on cover until it is fully engaged.

Typical Installation

Nonhazardous Area Hazardous Area

NGC-30

Control Panel

From
supply
voltage

• Additional replacement fuses may be purchased from an
Electrical Supply Distributor

Manufacturer Catalog no.
Wickmann 370-0200-041
or

Schurter 0034.6007

RMM2

RS-485

Optional - Use
if RTD is not
grounded
elsewhere

Conduit drain

From
supply
voltage

Raychem

Raychem

Raychem

6 | nVent.com

RTD

Conduit drain

Heating cable

E. INITIALIZE OR UPDATE THE NGC SYSTEM NETWORK AND ASSIGN SETTINGS FOR EACH RTD

RMM2
terminal no.

1

2

3

4

5

6

7

P&ID or Drawing
Identication Description or location

8

nVent.com | 7

North America

Tel [phone]
Fax [phone]

[e-mail]

Europe, Middle East, Africa

Tel [phone]
Fax [phone]

[e-mail]

Asia Pacific

Tel [phone]
Fax [phone]

[e-mail]

Latin America

Tel [phone]
Fax [phone]

[e-mail]

©2018 nVent. All nVent marks and logos are owned or licensed by nVent Services GmbH or its aliates. All other trademarks are the property of their respective owners.
nVent reserves the right to change specications without notice.

8 | nVent.com

Raychem-IM-H56848-RMM2-EN-1805

nVent.com