nvent RAYCHEM TraceTek TTDM, TTDM, TTDM-NMM, TTDM-SIM Installation Instructions Manual

TTDM Series

Leak Detection and Location Modules Replacement
Parts Installation Instructions

GENERAL INFORMATION

These instructions detail the steps to replace parts in the nVent
RAYCHEM TraceTek TTDM series leak detection and location
modules (catalog numbers TTDM, TTDM-NMM, and TTDM-SIM).
The modular design of the TTDM makes it possible to replace
individual boards—rather than the entire unit—if part of the module
is damaged or malfunctioning. These instructions explain how to

TRACETEK

install the replacement parts detailed below, except for the TTDM­UI-EPROM. Instructions for replacing the EPROM are covered in a
separate document (H55875) which is shipped with the EPROM.

These instructions for replacing parts are complemented by
instructions for installing the modules (document H55471 for
the TTDM and TTDM-NMM; H56314 for the TTDM-SIM).

The TTDM is an electronic unit. Its circuit boards should be
replaced only by a person qualified for work on electronic
instrumentation and controls.

TRACETEK TTDM REPLACEMENT PARTS

Catalog number Description

TTDM-4/20 TTDM 4-20 mA current transmitter board
TTDM-SI TTDM Sensor Interface board
TTDM-Relay TTDM relay
TTDM-PS1 TTDM power supply board, 115 Vac
TTDM-PS2 TTDM power supply board, 230 Vac
TTDM-PS24 TTDM power supply board, 24 Vdc
TTDM-fuse 200 mA, 250 V, quick-acting microfuses for TTDM-PS (bag of 5)
TTDM-MB TTDM motherboard
TTDM-RC1 TTDM ribbon cable, 6 inches long, with connectors installed
TTDM-UI TTDM User Interface assembly
TTDM-UI-EPROM-x TTDM-UI EPROM replacement; upgrades User Interface software to version indicated by x suffix. For new

features, see TTDM Software Release Bulletin H55874; instructions for replacing the EPROM are covered
in a separate document (H55875) shipped with the EPROM.

Storage

Keep replacement parts in a dry place prior to installation
to avoid possible damage to electronic components.

7 User Interface board

(not in TTDM-SIM)

8 4-20 mA board

(not in TTDM-SIM)
9 Sensor Interface board
10 Motherboard
11 Power supply board
12 Fuse (200 mA, 250 V)
13 Power cable terminal block
14 Ground/earth stud
15 Fault relay cable plug and

socket (not in TTDM-SIM)
16 Leak relay cable plug and

socket (not in TTDM-SIM)

17 Service relay cable plug and

socket (not in TTDM-SIM)

18 4-20 mA port plug and

socket (not in TTDM-SIM)

19 RS-232/485 port plug and

socket (not in TTDM-SIM)

20 Sensor Interface plug

andsocket

21 RS-485 plug and socket for

SIM network (only for use in
TTDM-NMM and TTDM-SIM)

22 Ribbon cable

(not in TTDM-SIM)

25 Relays

TOOLS REQUIRED

• Phillips (cross-head) screwdriver (for power supply
boards, motherboard, and User Interface assembly)

• Small flat-head screwdriver (for power supply and
other terminal blocks)

• 9/32 in nut driver (for User Interface assembly)

• 7 mm nut driver or wrench (if removing enclosure door
to replace User Interface assembly)

CAUTION:

Before disconnecting power to the TTDM
and replacing parts, alert any groups that
must respond to alarms signaled by the
TTDM (an emergency response team,
for example) that you will be working on

theunit.

TABLE OF CONTENTS—Instructions for Replacement Parts

4-20 mA current transmitter board A
Sensor Interface board B
Relays C
Power supply boards and fuse D

WARNING:

SHOCK HAZARD: Disconnect power to
the TTDM before opening enclosure door.

Important: After replacing one or more
parts following these instructions, test the
module in accordance with the module’s
installation instructions

PRECAUTIONS

Important: The TTDM is an electronic unit. When

replacing parts, take the following precautions to avoid
damage to its electronic components:

• Handle with care, avoid mechanical damage.

• Keep the electronics dry.

• If handling circuit boards, hold them by their edges to
avoid physical contact with electronic components.

• Avoid contamination with metal filings, liquids, or
other foreign matter.

(H55471 for a TTDM or TTDM-NMM,
H56314 for a TTDM-SIM).

Ribbon cable E
Motherboard F
User Interface assembly G
References for other parts H

A. REPLACING THE TTDM 4-20 MA CURRENT TRANSMITTER BOARD (NOT IN TTDM-SIM)

1. Remove old 4-20 mA board from the TTDM.

Remove the 4-20 mA current transmitter board.
Grasp the circuit board by its edges and pull up from
the motherboard. Gently rocking the board left to right
5° to 10° may help release the connection.

2. Install the new 4-20 mA board.

Position the new 4-20 mA current transmitter board;
orient the board so its markings are right side up. Before
applying pressure to seat the board, take care to align
the connectors along the top and bottom edges of the
4-20 mA board with their mating connectors on the
motherboard

2 | nVent.com

Top view of 4-20 mA board

Remove 4-20 mA board

Connectors

Instructions for Replacement Parts (Continued)

B. REPLACING THE TTDM SENSOR INTERFACE BOARD

1. Remove Sensor Interface (SI) plug from

socket on SIboard.

Pull out SI plug (feature 20) from its socket

on the old SIboard.

2. Remove old SI board.

Remove old SI board. If SI board is secured with
hold-down screws, remove the screws (2 places) and
store them. Grasp the circuit board by its edges and pull
up from the motherboard. Gently rocking the board top to
bottom 5° to 10° may help release the connection.

3. Install new SI board.

Position the new SI board; orient the board so its
markings are right side up. Before applying pressure to
seat the board, take care to align the connectors along
the left and right edges of the SI board with their mating
connectors on the motherboard. Gently rocking the
board top to bottom 5° to 10° may help seat the board,
which snaps into place when fully seated. If SI board
was secured with hold-down screws, insert and align
the screws, and use Phillips (cross-head) screwdriver to
tighten them hand tight.

4. If TTDM-NMM or TTDM-SIM, assign SIM address
to the new SI board.

If the module is a TTDM-NMM or TTDM-SIM (part of a
TraceTek leak detection network), the new SI board must
be assigned a SIM address following the instructions
on page 28 of the TraceTek TTDM-NMM and TTDM-SIM
System Operation and Maintenance Manual (H56313),
and on page 5 of the TraceTek TTDM-SIM Installation
Instructions (H56314). Note that address 01 is the
factory default of the SI board in the TTDM-NMM, but
this address must be assigned (following the procedure
referenced above) when a new SI board is installed.

5. Insert sensing cable plug into socket.

Insert SI plug into the SI socket on the new SI board

Sensor interface
board

Top view of SI board

Hold-down screw
(some units)

Sensor interface

plug and socket

Sensor interface
plug and socket

Connectors

Hold-down screw

(some units)

C. REPLACING A TTDM RELAY (NOT IN TTDM-SIM)

1. Remove old relay.

Rotate relay hold-down spring to the side, then pull relay
out of its socket in the motherboard.

2. Install new relay.

Carefully align leads from the relay with the sockets
on motherboard, then insert the relay leads into
motherboard. Rotate hold-down spring back into position
to retain the relay in place

25

TTDM relays

Hold-down

spring rotated

to release relay

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Instructions for Replacement Parts (Continued)

D. REPLACING THE TTDM POWER SUPPLY BOARD

Warning: SHOCK HAZARD. Confirm power to the TTDM

has been disconnected before opening enclosure door

and replacing the power supplyboard.

1. Disconnect the power wiring.

Use a small flat-blade screwdriver to disconnect the
power supply wires from the two-pin terminal block on
the power supply board (feature 13).

2. Remove the hold-down screws.

Use a Phillips (cross-head) screwdriver to remove
the hold-down screws at the top left and bottom right
corners of the power supply board.

3. Remove the old power supply board.

Grasp the circuit board by its edges and pull up from the
motherboard. Gently rocking the board top to bottom a
maximum 5° to 10° may help release the connection.

4. Install new power supply board.

Position the new power supply board; terminal block on
TTDM-PS1 or TTDM-PS2 should be in lower right corner.
Before applying pressure to seat the board, take care
to align the connectors along the left and right edges
of the SI board with their mating connectors on the
motherboard. Gently rocking the board top to bottom 5°
to 10° may help seat the board, which snaps into place
when fully seated.

Important: Confirm that the new power supply board has
the correct voltage rating for the supply voltage to be
used; do not exceed the maximum voltage rating of the
power supply board.

5. Reinstall hold-down screws.

Insert and align hold-down screws, and use Phillips
(cross-head) screwdriver to fasten them hand tight.

Important: Do not over tighten as this could damage
motherboard.

6. Reconnect the power wiring.

Connect the power supply wires to the two-pin terminal
block on the power supply board. Use L2 for neutral,

ifpresent.

Note: In the TTDM-PS24 board (which operates at

24Vdc or Vac), the terminal block for the power supply

wires is in the center of the board, rather than at the

lower right. For DC operation, polarity does notmatter.

Top view of

power supply board

Hold-down
screw

Terminal block
on TTDM-PS24

Connectors

Power supply

11

board

13

Terminal block

Terminal block
on TTDM-PS1
or TTDM-PS2 board

Hold-down screw

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Instructions for Replacement Parts (Continued)

E. REPLACING THE TTDM RIBBON CABLE (NOT IN TTDM-SIM)

1. Disconnect ribbon cable from motherboard and User
Interface (UI) assembly.

Release the fastening ears of the ribbon cable connectors
(as illustrated in Figure 1 at right), and pull the ribbon

cable away from the motherboard and the UIassembly.

2. Connect new ribbon cable to motherboard.

Orient the new cable so the single wide key protrusion
of a connector and the ribbon cable coming from that
connector both face up as illustrated in Figure2
(a connector cannot be inserted unless the key is
oriented correctly; the direction of the cable from the
connector can affect the stress to which the cable may
be subjected). Align the ribbon cable connector and
insert it into the motherboard connector (taking care not
to bend any pins). Press the ribbon cable connector into
the motherboard until the locking ears latch in place (as
illustrated in Figure 3).

3. Connect new ribbon cable to user interfaceassembly.

Align the ribbon cable connector and insert it into the UI
assembly (taking care not to bend any pins). Press the
ribbon cable connector into the UI assembly until the
locking ears latch in place.

Figure 1

PL

RS-485 EXT XMTRS

J10

1

ICOM485+ 485–

+51SO

123

Figure 2

RS-232/485 EXT COM PORT

1 1

RX/A TX/B RTS CTS +5V GND

4

56789

PL

PL

4-20mA OUT PORT

J13

J2

IRNT IOUT

10

11

12

Key

Slot

Figure 3

PL

RS-485 EXT XMTRS

J10

1

+51SO

ICOM485+ 485–

123

RS-232/485 EXT COM PORT

1 1

RX/A TX/B RTS CTS +5V GND

4

56789

PL

PL

4-20mA OUT PORT

J13

J2

IRNT IOUT

10

11

12

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Instructions for Replacement Parts (Continued)

F. REPLACING THE TTDM MOTHERBOARD

1. Disconnect ribbon cable from old motherboard.

Release the fastening ears of the ribbon cable connector,
and pull the ribbon cable from the motherboard. See
Figure 1 in Section E (page 6).

2. Disconnect the power wiring.

Warning: SHOCK HAZARD.

Use a small flat-blade screwdriver to disconnect the
power supply wires from the two-pin terminal block on the
power supply board (feature 13).

3. Remove plugs for external connections from sockets at
bottom of motherboard and sensor interface board.

• Mark each of the plugs for external connections so you

can readily plug them into the correct sockets on the
new motherboard.

• Remove each of the plugs for external connections

from its socket on the motherboard. The external
connections available in the TTDM are listed in the
table at right.

4. Remove 4-20 mA board from motherboard.

Remove 4-20 mA current transmitter board from old
mother-board (see step 1, Section A) and put it out of
harm’s way.

5. Remove old motherboard.

Unscrew the four Phillips (cross-head) screws that
hold the motherboard to the enclosure. Remove the
motherboard.

6. Remove daughterboards from old motherboard and
install them on new motherboard.

• Remove SI board from old motherboard and install on

new motherboard following instructions in Section B
(page 3).

• Remove relays from old motherboard and install on

new motherboard following instructions in Section C
(page 4).

• Remove power supply board from old motherboard

and install on new motherboard following instructions
in Section D (page 5).

7. Install new motherboard.

Position the new motherboard and fasten it in place with
the Phillips (cross-head) screws.

8. Install 4-20 mA board on new motherboard.

Install 4-20 mA current transmitter board on new
motherboard; see step 2 of Section A (page 2).

9. Insert plugs for external connections into sockets on new
motherboard.

Insert the plugs for the external connections into their
corresponding sockets on the new motherboard.

10. Reconnect the power supply wires.

Reconnect the power supply wires to the two-pin terminal
block on the power supply board. Use L2 for neutral, if
present (however, if using TTDM-24 at 24 Vdc, polarity does
not matter).

9 108 25

22

21

Feature no. Description of external connection

15 Fault relay
16 Leak relay
17 Service Required relay
18 4-20 mA port
19 RS-232/485 external communications

20 Sensor Interface
21 Leak detection network (TTDM-NMM and

serial port

TTDM-SIM only)

1920

18

4

Remove screws attaching
motherboard (four places)

151617

11. Connect ribbon cable to new motherboard.

Reconnect the ribbon cable, taking care not to bend any
pins in the connection. Press the connector into the
motherboard until the locking ears latch in place. See
Figure 2 in Section E (page 5).

11

13

6 | nVent.com

Instructions for Replacement Parts (Continued)

G. REPLACING THE TTDM UI ASSEMBLY (NOT IN TTDM-SIM)

Note: If the old UI is functioning, it is recommended that the

events history be printed out or downloaded through the
serial port (or recorded in some other manner) before the UI
assembly is replaced. All user-defined settings should also
be recorded in some manner, as a new UI assembly comes
with the factory defaults.

If the UI is not functioning, save the old UI assembly and
return it to RAYCHEM for diagnostic testing and/or download
of events and settings.

1. Disconnect ribbon cable.

Release the fastening ears of the ribbon cable connectors,
and pull the ribbon cable away from the UI assembly. See
Figure 1.

2. Place enclosure or enclosure door on horizontalsurface.

It is much easier to replace the user interface assembly if
the unit is on a horizontal surface. The easiest approach
may be to remove the TTDM enclosure from the location
where it is mounted, and place the complete unit on
the horizontal surface; for guidance on how to install—
or remove—the TTDM module, see the Installation
Instructions for TTDM Alarm and Locating Module,
H55471.

If it is not practical to move the entire TTDM unit, the door
can be removed from the enclosure. To remove the door
of the enclosure:

• Disconnect the ground/earth wire from the UI

assembly to the ground/earth stud inside the
enclosure; use 9/32 nut driver to remove locknut that
holds it in place.

• Use a 7 mm nut driver or wrench to remove the nuts

which hold the hinge (the hinge nuts are inside the
enclosure, as shown in Figure 2).

• After removing the nuts and nylon sealing washers,

put them in a safe place while you are replacing the UI
assembly.

3. Remove old UI assembly.

• Use 9/32 inch nut driver to remove the eight nuts

which secure the assembly to the enclosure door (see
Figure 3).

• Remove the eight flat washers and keep them with the

nuts.

• Lift the UI assembly off the enclosure door. Take care

not to damage the sealing gasket when doing so;
pull the assembly away gently, and then handle the
gaskets with care.

4. Position the gaskets on the inside of the panel door.

• Place the two spacer gaskets (of fiber construction

resembling paper) in position around the eight
mounting studs (see Figure 4).

• Place the foam sealing gasket in position inside the

eight mounting studs.

Figure 1

Figure 2

Figure 3

Figure 4

Fiber gasket
spacers (2)

Flat washer
and lock nut

Foam
sealing
gasket

Mounting
studs (8)

UI assembly

Ribbon cable

Hinge nuts

Ground/earth stud

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Instructions for Replacement Parts (Continued)

G. REPLACING THE TTDM UI ASSEMBLY (NOT IN TTDM-SIM) (CONTINUED)

5. Mount the UI assembly inside enclosure door.

• Place the TTDM UI assembly in position; the eight mounting
studs go through the eight slots on the UI assembly mounting
plate.

• Place flat washers (eight) on mounting studs.

• Position the ring tongue terminal of the UI ground (earth) wire
and the wire to the enclosure ground/earth over a mounting
screw as illustrated.

• Place a 8-32 locknut (with attached star lock washer) on each of
the eight mounting screws; fasten only hand tight.

Slot for

mounting

stud

• Look at the front of the panel, and align the UI assembly
so it is level (loosen nuts if necessary to reposition the UI
assembly). For the most attractive appearance, position the
sealing gasket so it is not visible inside the display opening;
the gasket can be tamped into place with a matchbook or
something similar, but take care not to damage it.

• Tighten the nuts after the display and gasket are properly
positioned. Use 9/32 inch nut driver to snug the nuts; do so by
hand; do not overtighten and risk damage to hardware.

6. Reconnect the ribbon cable.

Align the ribbon cable connector and insert it into the new UI
assembly (taking care not to bend any pins). Press the ribbon
cable connector into the UI assembly until the locking ears latch
in place.

7. Remount enclosure or enclosure door.

Remount the TTDM enclosure or the enclosure door (remounting or
reassembling, based on action taken at step 2).

Important: If enclosure door was removed, be sure to reconnect
ground/earth wire from UI assembly.

H. REFERENCES FOR REPLACING OTHER TTDM PARTS

Washer

Locknut

Ground wires
Washer

Mounting stud

Enclosure door

UI assembly

TDM-UI-EPROM-x

TTDM UI software can be upgraded by replacing the EPROM
on the UI assembly. The TTDM Software Release Bulletin
(document H55874) summarizes the features provided by
new software versions. Software upgrades are made available
in the form of an EPROM, together with the instructions for
replacing the EPROM (document H55875).

North America

Tel [phone]
Fax [phone]

[e-mail]

Europe, Middle East, Africa

Tel [phone]
Fax [phone]
[e-mail]

TERMINAL BLOCK CONNECTIONS

The TraceTek TTDM Leak Detection and Location Module
Installation Instructions (document H55471) describes how
to connect power wiring, relay wiring, and sensing cable to
the TTDM unit. The TTDM Installation and Operation Manual
(document H55472) provides connection details for the
4-20 mA port and the RS-232/485 serial port.

Asia Pacific

Tel [phone]
Fax [phone]
[e-mail]

Latin America

Tel [phone]
Fax [phone]
[e-mail]

nVent.com

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nVent reserves the right to change specications without notice.

RaychemTraceTek-IM-H56348-TTDMSeries-EN-1805 PN 197197-000