Dwyer Instruments MTL5041 Operating Manual

Instruction Manual

INM5000

MTL5000 Series
isolating interface units

ii

INM5000-6 Jul 2010

iii

1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

3 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

3.1 Installing unenclosed isolators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

4 ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

4.1 MTL5000 power bus - Installation and use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

4.2 Earth rail and tagging accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

5 DX ENCLOSURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5.1 Environmental conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

5.2 Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

5.3 Accessories in enclosures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

5.4 IS warning label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

6 UNIT DESCRIPTIONS, SETTING-UP, CONNECTIONS AND TESTING . . . . . . . . . . . . . . . . . . . . . . . 11

6.1 MTL5011 single-pole relay single-channel switch/proximity detector with phase reversal (Discontinued use MTL5011B) . . . . . . . . . . . . . . . 11

6.2 MTL5011B single-pole changeover relay single-channel switch/proximity detector with line fault detection and phase reversal . . . . . . . . . . . 12

6.3 MTL5012 solid-state single-channel switch/proximity detector with line fault detection and phase reversal . . . . . . . . . . . . . . . . . . . . . . . . 12

6.4 MTL5014 single-pole changeover relay single-channel dual-output switch/proximity detector with line fault detection and phase reversal . . . . 13

6.5 MTL5015 solid-state two-channel switch/proximity detector with line fault detection and phase reversal . . . . . . . . . . . . . . . . . . . . . . . . . . 14

6.6 MTL5016 single-pole relay two-channel switch/proximity detector with phase reversal (Discontinued, use MTL5018) . . . . . . . . . . . . . . . . . 15

6.7 MTL5017 single-pole relay two-channel switch/proximity detector with line fault detection and phase reversal . . . . . . . . . . . . . . . . . . . . . 15

6.8 MTL5018 single-pole, changeover relay, two-channel, switch/proximity detector with line fault detection and phase reversal . . . . . . . . . . . . 16

6.9 MTL5018AC single-pole, changeover relay, two-channel, switch/proximity detector with line fault detection and phase reversal . . . . . . . . . 16

6.10 MTL5021 loop-powered solenoid/alarm driver, IIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

6.11 MTL5022 loop-powered solenoid/alarm driver, IIB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

6.12 MTL5023 solenoid/alarm driver with line fault detection and phase reversal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

6.13 MTL5024 solenoid/alarm driver, logic drive with phase reversal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

6.14 MTL5025 low-current loop-powered solenoid/alarm driver, IIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

6.15 MTL5031 vibration transducer interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

6.16 MTL5032 pulse isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

6.17 MTL5040 2-channel 4 to 20mA loop isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

6.18 MTL5041/42 repeater power supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

6.19 MTL5043 repeater power supply dual output, 4 to 20mA for 2-wire transmitters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

6.20 MTL5044 repeater power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

6.21 MTL5045/46 isolating drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

6.22 MTL5048 analogue input/output, loop-powered isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

6.23 MTL5049 two-channel isolating driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

6.24 MTL5051 serial data comms isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

6.25 MTL5053 isolator/power supply for 31.25kbit/s fieldbuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

6.26 MTL5061 two-channel loop-powered fire/smoke detector interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.27 MTL5074 temperature converters, THC or RTD input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6.28 MTL5081 millivolt isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.29 MTL5082 resistance isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.30 MTL5099 dummy isolator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.31 MTL5113P fail-safe switch/proximity detector interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.32 MTL5314 trip amplifier for 2– or 3– 2 wire transmitters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.33 MTL5344 Repeater power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.34 MTL5349 two-channel isolating driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.35 MTL5991 24V dc power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.36 MTL5995 fieldbus power supply for 31.25kbit/s fieldbuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.37 FBTI-IS fieldbus terminator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

CONTENTS Page

© 2010 MTL Instruments Group plc. All rights reserved.

INM5000-6 Jul 2010

iv

INM5000-6 Jul 2010

7 MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

7.1 Routine maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

7.2 Enclosures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

8 OTHER USEFUL DOCUMENTATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

9 APPENDIX A - INSTRUCTIONS FOR MTL5500 SERIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

9.1 MTL5521 rotational speed monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

9.2 MTL5531 voltage/current converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

9.3 MTL5536 potentiometer converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

1

INM5000-6 Jul 2010

WARNING

This manual describes the use and installation of safety
equipment. This equipment must be installed, operated
and maintained only by trained competent personnel and
in accordance with all appropriate international, national
and local standard codes of practice and site regulations
for intrinsically safe apparatus and in accordance with
the instructions contained here.

ATEX

If the country of installation is governed by the Essential Health and
Safety Requirements (Annex II) of the EU Directive 94/9/EC [the ATEX
Directive - safety of apparatus] then MTL document INA5000 must
be consulted before installation.

CERTIFICATION DATA

The MTL web site

http://www.mtl-inst.com

contains documentation
regarding intrinsic safety certification for many locations around the
world. Consult this data for information relevant to your local certifying
authority.

REPAIR

These products MUST NOT be repaired. Faulty or damaged
products must be replaced with an equivalent certified product.

1 INTRODUCTION

This instruction manual explains how to install, connect, test and
maintain MTL5000 Series isolating interface units (isolators).

2 DESCRIPTION

MTL5000 Series isolators provide intrinsically safe (IS) communication
and signal conditioning for a wide range of hazardous-area devices.
Total ac and dc isolation exists between input, output and power supply
on separately powered units, and between input and output on loop­powered units. No IS earth is required. DIN-rail mounting and plug-in
signal and power connectors simplify installation and maintenance.
Units are powered from a 20 to 35V dc supply, or, in some cases, from
the signal itself.

3 INSTALLATION

Mount all MTL5000 Series isolators on low-profile (7mm) or high-profile
(15mm) type T35 (top-hat) DIN-rail to EN50022, BS5584, DIN46277.
This is available from MTL, in 1 metre lengths (THR2 DIN rail). Install
isolators within the safe area unless they are enclosed in approved
flameproof, pressurised or purged enclosures and ensure that the local
environment is clean and free of dirt and dust. Note the ambient
temperature considerations of section 3.1.7.

It is recommended that, in normal practice, the DIN rail is earthed to
ensure personnel safety in the event of mains being put accidentally on
the rail.

3.1 Installing unenclosed isolators

On new installations, if isolators are mounted in several rows orcolumns,
mount alternate rows or columns so that units face in opposite directions.
This allows safe- and hazardous-area wiring looms to be shared.

See figure 3.1 for isolator dimensions.

INM5000-6

July 2010

Note: All MTL products are tested for electrical safety to EN 61010 to

comply with the EC Low Voltage Directive

MTL5000 Series Interface units

Figure 1.1: MTL5000 Series isolators

2

INM5000-6 Jul 2010

3.1.1 Mounting isolators on DIN rail

Clip isolators onto type T35 DIN rail as shown in figure 3.2, with the
blue signal plugs facing towards the hazardous-area wiring.To remove
an isolator from the rail, insert a screwdriver blade into the clip as shown
and lever the clip gently outwards; pivot the isolator off the rail. Allow a
maximum mounting pitch of 16.2mm for each unit.

3.1.2 Wiring up isolators

Each unit is supplied with the appropriate number and type of safe- and
hazardous-area connectors (see figure 3.3), as dicatated by the
terminals used and the type of power supply. Loop-powered devices do
not require power connectors. Depending on the installation, it may be
easier to wire up isolators with power and signal plugs either in place
or removed. Either way, allow sufficient free cable to permit plugs to be
removed easily for future maintenance and/or replacement purposes.
See section 6 for individual unit wiring instructions.

Note: Units for use with 31.25kbit/s fieldbuses may require additional
terminators to be fitted. See section 6.33 for details of MTL's FBT1
fieldbus terminator.

Signal and power conductors

Removable signal and power plugs are fitted with screw clamp
terminals. Note that the conductors should be between 14 and 24 AWG
(1.6 and 0.5mm dia) in size. Signal plugs, located on top of the
modules, are mechanically keyed to fit in only one position. They are

coloured grey, for safe-area connections, and blue, for hazardous-area
connections.

For externally powered units, a power plug slots into the socket at
terminals 13 and 14 on the safe-area side of each module. The socket
is coloured blue if the unit is dc powered. Power plugs are coloured
grey, for plugging into the blue sockets of dc powered units.

Making connections

a) Trim back the insulation of conductors by 12mm.
b) Check the terminal assignments shown in section 6 or on the

side label of the unit.

c) Insert conductors according to the terminal assignments and

tighten screws.
If the wires are to be fitted with crimp ferrules, the following is a list of
those recommended with required trim lengths for each:

*2- to 3-week lead time

† These ferrules have 18mm length metal tubes which should be cut to
12mm after crimping

Note: Smaller section wire than that stated can often be successfully
used if the crimping is good.

Crimp tool: Phoenix Contact Crimpfox UD6 part number 1204436

Finishing

Wire up individual isolators in accordance with wiring schedules. Daisy­chain power supply connections between individual power plugs or use
the power bus (see section 4.1).

Segregate hazardous- and safe-area wiring into separate trunking or
looms wherever possible to avoid errors and maintain a tidy installation.

Use an MTL5099 dummy isolator to provide termination and earthing
for unused cores from the hazardous area.

Hazardous-area
connections

Non-hazardous
(safe) area
connections

Power
connectors

104

115

110

16

16.2 pitch

Plug Entry Wire Metal tube Trim Recommended ferrules
type size length length

(mm2) (mm) (mm)

Signal Twin 2x1.5 12 14 Cembre PKET 1512
Signal Single 0.75 12 14 Weidmuller 902591
Signal Single 1.0 12 14 Cembre PKC112
Signal Single 1.0 12 14 Phoenix Contact AI 1-12 RD

(3200674)*
Signal Single 1.5 12 14 Cembre PKE1518†
Signal Single 2.5 12 14 Cembre PKE2518†
Power Twin 2x0.75 10 12 Cembre PKET7510
Power Twin 2x0.75 10 12 AMP (non-preferred) 966144-5
Power Twin 2x1.0 10 12 Phoenix Contact AI-TWIN 2X 1-10 RD
Power Single 0.75 10 12 AMP 966067-0
Power Single 1.0 10 12 Phoenix Contact AI 1-10 RD

Figure 3.1: Dimensions of MTL5000 Series isolators

Figure 3.2: DIN rail – mounting and removing isolators

12mm

14mm

Power Plugs

Grey: dc supplies (PWR5000)

Signal Plugs

Grey: safe-area side
Blue: hazardous-area side

Figure 3.3: Removable power and signal plugs

Consult table below for

additional details.

Note: the open circuit window (between 350µA and 50µA) is not
hysteresis, all MTL5000 Series modules with inputs conforming to
NAMUR/DIN 19234 will switch between open and complete circuit
conditions within these limits.

Note: the short circuit window (between 100

Ω

and 360Ω) is not
hysteresis, all MTL5000 Series modules with inputs conforming to
NAMUR/DIN 19234 will switch between open and complete circuit
conditions within these limits.

Modules with LFD and inputs conforming to NAMUR/DIN
19234:

MTL5011B, 5014* and 5018: LFD enable switch on top label

* The MTL5014 has a Slave/LFD output relay arrangement
(see module description in section 6).

MTL5012 and 5015: LFD enable switch on top label

MTL5017: LFD permanently enabled

Other modules with LFD facility

MTL5023 solenoid/alarm driver: LFD automatic

MTL5046 isolating driver: LFD automatic

Note: The safe-area circuit impedance will increase with hazardous­area load and will rise >150kΩ for the 'open circuit' line fault.

MTL5113x: LFD automatic

Hazardous-area load Safe-area input

<50Ω High impedance (>150kΩ)
>90Ω Normal operation

Hazardous-area input (either channel) Line-fault-detect relay

<50µA De-energised

>350µA Energised

>360Ω Energised
<100Ω De-energised

LFD switch setting Hazardous-area input(s) Solid-state output(s)

On <50µA Non-conducting
On >350µA Conducting
On >360Ω Conducting
On <100Ω Non-conducting

LFD switch setting Hazardous-area input(s) Output relay(s)

On <50µA De-energised
On >350µA Energised
On >360Ω Energised
On <100Ω De-energised

3.1.3 Phase reversal

Switch(es) to change the phase of the output(s) relative to the input(s) are
provided on the top labels of some of the MTL5000 Series modules and
on the base of others. The following applies:

MTL5011B, 5014 and 5018: Phase reversal switch on top label

MTL5017: Phase reversal switch on base of module

MTL5012 and 5015: Phase reversal switch on top label

MTL5023 and 5024: Phase reversal switch on base of module

Positions for base-located switches are set as shown in figure 3.4.

3.1.4 Line fault detection (LFD)

Line fault detection on hazardous-area sensor lines (open circuit or short
circuit) is provided on some MTL5000 Series modules.

Note: resistors must be fitted when using the LFD facility with a contact
input: 500Ωto 1kΩin series with switch and 20kΩto 25kΩin parallel
with switch.

For hazardous-area inputs conforming to NAMUR/DIN
19234, a line fault condition is indicated as follows:

Open circuit condition if hazardous-area current <50µA
Line integrity (no open circuit) if hazardous-area current >350µA
Short circuit condition if hazardous-area load <100Ω
Line integrity (no short circuit) if hazardous-area load >360Ω

A

B2

1

Normal Reverse

CH1

CH2

Label face

Base of unit

3

INM5000-6 Jul 2010

PR switch setting Hazardous-area input(s) Output relay(s)

Off <1.2mA De-energised
Off >2.1mA Energised
On <1.2mA Energised
On >2.1mA De-energised

PR switch setting Hazardous-area input(s) Solid-state output(s)

Off <1.2mA Non-conducting
Off >2.1mA Conducting
On <1.2mA Conducting
On >2.1mA Non-conducting

Hazardous-area

PR switch setting Safe-area control output

o ← (off) CTRL+Ve >4.5V above CTRL-Ve Enabled
o ← (off) CTRL+Ve <1.4V above CTRL-Ve Disabled

→ + (on) CTRL+Ve >4.5V above CTRL-Ve Disabled
→ + (on) CTRL+Ve <1.4V above CTRL-Ve Enabled

Hazardous-area load Solid-state LFD output

<50Ω Non-conducting
>7kΩ Non-conducting

Hazardous-area input LFD output

< 50µA (open-circuit) de-energised

> 6.6mA (short-circuit) de-energised

Figure 3.4: Phase reversal switch on base of units

PR switch setting Hazardous-area input(s) Output relay(s)

o ← (off) <1.2mA De-energised
o ← (off) >2.1mA Energised

→ + (on) <1.2mA Energised
→ + (on) >2.1mA De-energised

4

INM5000-6 Jul 2010

3.1.5. Relay outputs

Reactive loads on all units with relays should be adequately
suppressed.Changeover relay outputs are provided on the following
units: MTL5011B, MTL5014, MTL5018 and MTL5314. In order to
achieve maximum contact life, a minimum switching current of 10mA at
≥5V is recommended.

3.1.6 Earth leakage detection

An MTL4220 earth leakage detector can be used with a number of
MTL5000 Series units to detect hazardous-area earth faults which can
then be rectified without needing to shut down the loop ('no-fail'
operation). On units with a single-channel input, the MTL4220 is
connected to terminal 3 and on units with two-channel inputs, to
terminals 3 and 6. Units which can be used with an MTL4220 are:

MTL5011B MTL5012 MTL5014 MTL5015
MTL5017 MTL5018 MTL5021 MTL5022
MTL5023 MTL5024 MTL5025 MTL5061

N.B. HAZ1-3 or HAZ4-6 connectors are required.

3.1.7 Ambient temperature considerations

Ambient temperature limits for unenclosed MTL5000 Series isolators are
from -20°C to +60°C with units close-packed.

4 ACCESSORIES

4.1 MTL5000 power bus - Installation
and use

4.1.1 MTL5000 Series power bus

Power bus kits provide facilities for linking the power supply terminals
(13 and 14) of up to 32 installed MTL5000 Series units to a standard
24V power supply. Buses consist of chains of power plugs and are
available in different lengths to suit various numbers of modules as
follows:

4.1.2. Installation

4.1.2.1 Check to make sure the bus length is correct for the

number of modules involved.

4.1.2.2 If the number of modules is less than the maximum number
the chain will support, cut off the surplus power plugs at
the tail end of the chain - leaving a 'new' tail end.

4.1.2.3 Insert power plugs into the power terminals on the safe­area side of each module in sequence.

4.1.2.4 Connect the power supply source to the tail end of the
chain (using the insulation displacement connectors
(Scotchloks) provided if required).

Notes:

1. To reduce the risk of excessive voltage drop or over­current, DO NOT connect power buses in series.

2. Surplus sections can be used (and, if required)
connected together provided the cut ends are safely
terminated and/or connected together. Use single
ferrules with a crimp tool or insulation displacement
connectors (Scotchloks). Suitable ferrules and connectors
are provided with the kits.

4.2 Earth rail and tagging accessories

This section explains how to specify and assemble earth rail and tagging
strip accessories for the MTL5000 Series.

The accessories consist of mounting brackets, earth rails, tagging strips
and associated parts. They provide facilities for earthing, terminating
cable screens and tagging (identifying) the positions of individual units.

4.2.1 Parts list
IMB57 Insulating mounting block (figure 4.5)

One required at each end of a tagging strip/earth rail. Suitable for low­profile (7.5mm) and high-profile (15mm) symmetrical DIN rail.

ERB57S Earth-rail bracket, straight (figure 4.6)

Nickel-plated; supplied with two push fasteners, one earth-rail clamp
(14mm, 35mm

2

) and one earth cable clamp (10mm, 16mm2).

Note: ERB57S is the preferred choice of earth-rail bracket. It is usually
fitted in the upper slot on insulating mounting block IMB57

.

Number of modules Kit ID code

(contains grey power plugs for 24V dc supply)

1 to 8 PB-8T

9 to 16 PB-16T
17 to 24 PB-24T
25 to 32 PB-32T

 +

Optional insulation

displacement

connectors

x2

OR

Figure 4.1: Installing a chain of power plugs into MTL5000
Series modules

Figure 4.2: Using crimp ferrules or insulation displacement
connectors (Scotchloks) to terminate cut ends

133.5mm

16mm

2

35mm

2

16mm235mm

2

10mm

3mm

14mm

10mm

14mm

10mm

5

INM5000-6 Jul 2010

Where the earth rail is required to be positioned at a lower height and
to allow access to the IMB57 mounting screws, the straight earth-rail
bracket ERB57S can be inserted in the lower slot, but only after
insulating mounting blocks IMB57 are clamped to the DIN rail. This may
not be possible if, for example, trunking is fitted. In this case, fit offset
earth-rail bracket ERB57O (see figure 4.7) in the upper slot: the
mounting blocks can then be fitted in a restricted space with this bracket
already fitted.

ERB57O Earth-rail bracket, offset (figure 4.7)

Nickel-plated; supplied with two push fasteners, one earth-rail clamp
(14mm, 35mm2) and one earth cable clamp (10mm, 16mm2).

ERL7 Earth rail, 1m length (figure 4.8)

Nickel-plated; may be cut to length.

TAG57 Tagging strip, 1m length (figure 4.9)

Cut to size. Supplied with tagging strip label.

TGL57 Tagging strip labels, set of 10 x 0.5m

Spares replacement, for use with TAG57 tagging strip.

MS010 DIN rail module spacer, 10mm, pack of 5 (figure 4.10)

Grey spacer, one required between each MTL5995 and any adjacent
module on a DIN rail, to provide 10mm air-circulation space between
modules.

TGL57

TAG57

ERB57

ERB570

ETM7

Snap off extension
when using IMB57
as central support

10mm Earth
clamp

ERB57S
in upper
position

ERB57S
in lower
position

IMB57

Push
fastener

14mm
Earth-rail
clamp

ERL7

82mm

135mm

28mm

66mm

15mm

150mm

10mm

3mm

16mm

2

35mm

2

16mm235mm

2

10mm

14mm

10mm

14mm

3mm

10mm

THR2

IMB57

ERL7

HAZ1-3

HAZ4-6

TH5000

TAG57

TGL57

SAF7-9

SAF10-12

ERB57S

PWR5000

ETM7

Figure 4.3: Assembly drawing showing part numbers

Figure 4.4: Mounting details

Figure 4.5: IMB57 Insulating mounting block

Figure 4.6: ERB57S Earth-rail bracket, straight (end-on view), and clamps

Figure 4.7: ERB57O Earth-rail bracket, offset (end-on view), and clamps

Figure 4.8: ERL7 Earth-rail, 1m length

31mm

Figure 4.9: TAG57 Tagging strip,1m length

x 5

Figure 4.10: MS010 DIN rail module spacers

Type A

Type B

6

INM5000-6 Jul 2010

ETM7 Earth terminal, bag of 50 (figure 4.11)

For terminating cable screens and 0V returns on the ERL7 earth rail.
For cables ≤ 4mm

2

.

TH5000 Tag holder

Spares replacement.

Connectors

Spares replacement: HAZ1-3, HAZ4-6, HAZ-CJC, PWR5000, SAF7-9,
SAF10-12 (SAF1-3 and SAF4-6 grey connectors, also available for use
in safe-area applications).

4.2.2 Assembly

4.2.2.1 Fitting earth rails
a)

In upper position

Before fitting insulating mounting blocks IMB57, check that the
swing nuts in the base of each unit are turned back into the
moulding. Locate the mounting blocks on the DIN rail in the
chosen position and tighten the screws (see figure 4.12). Check
that the swing nuts rotate correctly to locate underneath the
flanges of the DIN rail.

Slide a straight earth-rail bracket ERB57S into the upper slot in
each mounting block. Push two plastic push fasteners into each
bracket to locate the brackets in the mounting blocks.

Cut earth rail ERL7 to the length needed. Slide the required
number of ETM7 earth terminals (5mm or 7mm wide) onto the
rail. Clamp each end of the earth rail to earth-rail brackets
ERB57S using the terminal clamps (14mm, 35mm

2

) supplied. Fit
an earth clamp (10mm, 16mm2) to the free end of each earth-rail
bracket.

Note: For lengths of earth-rail greater than 500mm,
provide additional support by installing a third IMB57 mounting

block and earth-rail bracket, mid-way between the end mounting
blocks. Snap out the perforated extension between the lugs on
this mounting block if a continuous tagging strip is to be fitted
(see figure 4.3).

b)

In lower position

, where at least 150mm clearance exists

on one side, measured from the edge of the mounting
block.
As for a), but slide earth-rail brackets ERB57S into the

lower slots in each mounting block.

c)

In lower position, where there is insufficient clearance to fit
earth-rail brackets ERB57S.

As for a), but slide offset earth-rail brackets ERB57O into
the upper slot in each mounting block before assembling
the mounting blocks to the DIN rail. ERB57S brackets
cannot be used because they obscure the mounting
blocks' fixing screws.

4.2.2.2 Fitting tagging strips

Assemble mounting blocks IMB57 to the DIN rail as above. Cut TAG57
tagging strip and label to the length needed, and insert label so that the
appropriate side is visible. Clip the strip onto the lugs on the mounting
blocks. Hinge up the strip to provide access to the tops of the isolators.

Note: If necessary, provide additional support for long lengths of
tagging strip by installing an extra IMB57 mounting block mid-way
between the end mounting blocks. Snap out the perforated extension
between the lugs on this mounting block.

4.2.3 Completed assemblies

Figure 4.13(below) illustrates a complete assembly of MTL5000 isolators
using the accessories mentioned above.

The broken-line boxes either side of the assembly represent cable
trunking, and the accompanying dimensions represent the minimum
spacing between trunking and assemblies.

For further information on the use of the accessories please refer to the
relevant MTL customer drawings listed in section 8.

5.5
mm

7mm

Type A Type B

110mm110mm

Figure 4.11: ETM7 Earth terminal

Figure 4.12: Fitting IMB57

Figure 4.13: MTL5000 Series - complete assembly

7

INM5000-6 Jul 2010

5 DX ENCLOSURES

Enclosures are usually selected on the basis of the number of units they
will accommodate and table 5.1 shows the capacity of each of the
enclosures. Figures 5.2 to 5.4 show each type of enclosure containing
MTL5000 modules.

Table 5.1: DX range of enclosures - module capacities

* Use these figures when two IMB57 mounting brackets for
tagging/earth-rail accessories are included

Note: The user should be aware that some workshop preparation may
be required for the cable gland plates before the enclosure is ready for
on-site installation.

131 (inside)

150

184

147 (inside)

Top of DIN rail

270

540

430

184

147 (inside)

Top of DIN rail

170

102 102

360

270

DX430

DX070

125

70

175

DX170

8080

Enclosure MTL5000 isolators

16.2 mm mounting pitch

DX070 4 (2*)
DX170 10 (8*)
DX430 26 (24*)

MTL5000 Series
Isolators

Figure 5.1: MTL’s DX range of enclosures

Figure 5.2: DX070 enclosure showing MTL5000 modules

mounted

8

INM5000-6 Jul 2010

5.1 Environmental conditions

Environmental conditions that should be taken into account when
installing DX enclosures include:-

See section
Maximum ambient temperature limits 5.1.1
Storage temperatures 5.1.2
Humidity 5.1.3
Corrosion resistance 5.1.4
Flammability 5.1.5
Impact resistance 5.1.6
Chemical resistance 5.1.7

5.1.1 Maximum outside enclosure

temperature limits

The maximum outside enclosure temperature depends upon the total
power dissipated by the installed modules which, in turn, depends upon
their number and type. It can also be influenced by the Authority whose
standards may need to be applied to the system, e.g. BASEEFA
(CENELEC), Factory Mutual Research Corporation, Canadian
Standards Association.

Figure 5.5 shows, in graphical form, the maximum outside enclosure
temperatures (T

MO

) for given levels of power dissipation.

The graph was derived from the following equation and should be used
to calculate accurately the suitability of any particular mix of modules.

T

MO

= 60°C - δT

where δT= k

1

x P
P = total power (watts) dissipated by modules in an enclosure
k

1

= is a dissipation constant for a given enclosure and

module series. Select the relevant value from table 5.2.
(60°C is the temperature inside the enclosure)

Table 5.2: Dissipation constant k

1

for enclosures (°C/watt)

Orientation of the enclosures is also important - the optimum position
being on a vertical surface with the internal DIN-rail horizontal as shown
in figure 5.6. Any other position can reduce the maximum allowable
ambient temperature by up to 5°C.

Examples

Tables 5.3 and 5.4 list likely combinations of MTL5000 Series modules
in the three enclosure types and indicate the acceptable maximum
permitted outside enclosure temperature for these based on the graph in
figure 5.5. See the specifications included in the latest version of MTL's
IS catalogue for the power dissipation figures of individual MTL5000
Series modules.

5.1.2 Storage temperatures

Storage temperatures are safe within the range -40°C to +80°C.

5.1.3 Humidity limits

Safe humidity limits are within the range 5 to 95% RH.

MTL5000 Series Isolators

MTL5000 Series Isolators

DX070 DX170 DX430

MTL5000 4.03 1.88 0.82

60

40

20

10

30

50

0

10 20 30 40

Power dissipation (watts)

Max. outside enclosure

temperature (°C)

Enclosures

DX070
DX170
DX430

Figure 5.3: DX170 enclosure showing MTL5000 modules
mounted

Figure 5.4: DX430 enclosure showing MTL5000 modules
mounted

Figure 5.5: Graph depicting outside enclosure temperature
limits for DX enclosures used with MTL5000 Series isolators

Figure 5.6: Optimum orientation for wall-mounted enclosure

9

INM5000-6 Jul 2010

Table 5.3: Typical mix of MTL5000 Series modules

Table 5.4: Power versus maximum outside enclosure temperature

5.1.4 Corrosion resistance

The effect of corrosion on DX enclosures is negligible.

5.1.5 Flammability rating

The flammable properties of the materials used in the construction of the
enclosures are well understood by manufacturers and ratings have been
established to a number of standards. One of the better known
standards is the Underwriter's Laboratory standard UL 94 and the
ratings for the enclosure materials are given as:

Materials UL94 rating
Polycarbonate (all lids) V2/V0
Polycarbonate with glass reinforcement (DX070 base) V1/V0
Polyester with glass reinforcement (DX170 & DX430 bases) V0
Items made from similar materials are well established as suitable for use

in process I/O marshalling areas.

5.1.6 Impact resistance

The enclosure designs have been tested to an impact resistance of
greater than 2 Joules which exceeds the BS EN 61010-1 requirements
of 0.5 Joules.

5.1.7 Chemical resistance

The overall chemical resistance of the enclosures is limited by the
resistance of the transparent polycarbonate lid. The glass-reinforced
polycarbonate/polyester (GRP) bases have a higher resistance than
plain polycarbonate. Table 5.5 lists qualitative evaluations of resistance
to a variety of chemical agents.

5.2 Mounting

5.2.1 General

These instructions are concerned solely with mounting the DX enclosures.
Instructions for wiring and testing individual modules within the
enclosures are provided in Section 6.

Sufficient space is provided within the enclosures to accommodate
tagging and earth-rail accessories but this is at the expense of a
reduction in the number of modules that can be fitted.

5.2.2 Location and orientation

5.2.2.1 Location

The DX enclosures are intended for safe (non-hazardous) area use.
In N. America or Canada (because the enclosures are rated NEMA 4X)

they can be used in Class 1, Division 2 (gases) location, but check with
local requirements and ensure all cable entries also conform. In this case,
an additional warning label will be required on or near the enclosure
warning that the MTL5000 interfaces must not be removed unless the
area is known to be non-hazardous. The enclosures are NOT suitable
for Class II or III, Division 2 hazardous locations.

5.2.2.2 Orientation

As noted earlier (see section 5.1.1 and figure 5.6), for optimum
temperature performance the enclosures should be mounted on a vertical
surface with the internal DIN rail horizontal.

5.2.3 Mounting details

See figures 5.7 to 5.9 for the dimensions and mounting hole distances,
etc., of the three DX enclosures. The recommended method of mounting­described here-uses the four wall-mounting lugs supplied with each
enclosure. An alternative method of mounting is by direct attachment to
the mounting surface through the corner holes.

Note: When the wall-mounting lugs are used to attach the enclosures,
the overall depth of the enclosure is increased by an additional 3.3 mm
(DX070) or 7 mm (DX170 and DX430).

a) At each of the four corner fixing holes, insert one of the

screws provided and use it to attach a fixing lug to the
base of the enclosure.

b) Each lug can be used in one of two positions as shown in

figures 5.7 to 5.9.

c) Attach the lugs to the mounting surface with suitable fasteners.
d) Diameters of fixing holes in lugs are 5.5mm (DX070) and

7.0mm (DX170 and DX430)

e) Appropriate fixing hole distances are shown in figures 5.7

to 5.9.

Power dissipation Maximum outside

Enclosure Modules installed of modules in watts (P) enclosure temp. (T

MO

)°C

DX070 2xMTL5011B + 2xMTL5044 (2x0.75) + (2x1.5) = 4.5 41.9
DX170 5xMTL5011B + 5xMTL5044 (5x0.75) + (5x1.5) = 11.25 38.9
DX430 13xMTL5011B + 13xMTL5044 (13x0.75) + (13x1.5) = 29.25 36.0

Table 5.5: Qualitative evaluations of resistance to various
chemical agents

Qualitative evaluation

Chemical agents of resistance

Salt water; neutral salts; acids (low concentrations); hydraulic oil Excellent
Alcohols Very good
Acids (high concentrations); alkalis (low concentrations); petrol; cooling fluids Good
Alkalis (high concentrations); solvents. Poor

Number of k

1

Power dissipation Maximum outside

Enclosure installed modules °C/watt of modules in watts (P) enclosure temp. (T

MO

) °C

DX070 4 4.03 4.0 43.9

4 4.03 6.0 35.8

DX170 10 1.88 10.0 41.2

10 1.88 15.0 31.8

DX430 26 0.82 21.6 42.3

26 0.82 39.0 28.0

5.2.4 Cable glanding

All cables into the enclosures must be glanded to IP65 standards to
maintain this rating for the enclosure as a whole. Cable glands and
gland plates are not supplied. Glanding requirements vary for each
enclosure as follows:

DX070

On the DX070, 'knockout' holes are provided, in two different sizes
(15.5 mm and 21 mm), on the side faces of the base. See table 5.7 for
recommended cable glands.

Note: The enclosure may have three or four knockout holes on each
side depending on the manufacturer. Consequently, there may be a
choice of either six or eight positions for cable glands.

DX170

The DX170 can accommodate one gland plate on each side - see figure

5.10 for details. Table 5.6 lists suppliers of suitable gland plate kits and
Table 5.7 lists recommended glands.

DX430

The DX430 can accommodate two gland plates on each side - see figure

5.11 for details. Table 5.6 lists suppliers of suitable gland plate kits and
Table 5.7 lists recommended glands.

10

INM5000-6 Jul 2010

107

137

157

187

Ø 5.5

520

576

249

305

Ø 7.0

Gland plate

Typical gland

positions

Gland plate

Typical gland

positions

249

305

339

395

Ø 7.0

Figure 5.7: Dimensions and location of fixing holes - DX070

Figure 5.8: Dimensions and location of fixing holes - DX170

Figure 5.9: Dimensions and location of fixing holes - DX430

Figure 5.10: Cable gland plate locations on a DX170 enclosure

Figure 5.11: Cable gland plate locations on a DX430 enclosure

11

INM5000-6 Jul 2010

Sarel (UK) Tel[phone]
Bowthorpe Hellermann (UK) Tel [phone]

Table 5.7: Recommended cable glands for use with DX enclosures.

Weidmuller (UK) Tel [phone]
Sarel (UK) Tel [phone]

5.3 Accessories in enclosures

Apart from mounting, there are some other installation details which
should be considered before adding the appropriate interface modules
and making the necessary cabling connections.

A range of accessories is available to accompany the MTL5000 units
(see section 4). Further details of these accessories are provided in
product sheet EPS57ACC and instruction manual INM57ACC but the
following points should be observed.

5.3.1 Insulating mounting block (IMB57)

A pair of these can be attached to the DIN rail, at either end of the
modules, to provide a mounting for earth rails. Use of mounting blocks
will reduce the space available for isolator modules.

5.3.2 Earth rails (ERL7)

Earth rail is produced in 1 metre lengths and will require cutting to length
before mounting. ERL7 earth rails can be mounted either side of the
modules but are typically mounted on the hazardous side of the DIN rail.

5.3.3 Tagging strip (TAG57 and TGL57)

Tagging strip is produced in 1 metre lengths and will require cutting to
length before mounting. Similarly, the labels will require cutting to fit the
tagging strip.

5.4 IS warning label

A 'Take Care' IS warning label is provided inside each enclosure. This
should be attached to the inside of the transparent lid when its
orientation has been established.

6 UNIT DESCRIPTIONS, SETTING-UP,

CONNECTIONS AND TESTING

For each MTL5000 Series unit, this section describes the function
(briefly), the setting-up procedure, wiring connections and includes a
simple functional test. For a fuller functional description and a detailed
technical specification, refer to the appropriate entry in MTL's current IS
catalogue.

The functional tests can be carried out during commissioning or later, for
fault finding. If a fault is suspected, first check that the power LED is lit
(not applicable to loop-powered devices). If necessary, check that all
signal and power plugs are properly inserted, that no wires are loose
and that the unit is mounted correctly. If operation is still suspect, carry
out the tests. They establish whether power supplies are connected
properly and whether the isolator is operating correctly. Please return
units that fail these tests to the supplier.

6.1 MTL5011 single-pole relay single­channel switch/proximity detector
with phase reversal
(Discontinued use MTL5011B)

The MTL5011 enables a safe-area load to be relay-controlled by a
switch or proximity detector located in a hazardous area. Output phase
reversal (see 3.1.3) is provided.

6.1.1 Wiring connections

See figure 6.1 for wiring connections.

Note: Reactive loads must be adequately suppressed

Manufacturer/agent Manufacturer’s part number

Enclosure DX170 Enclosure DX430

Bowthorpe Hellermann TL-27/360 TL-27/270
Sarel 21128 21127

Table 5.6: Recommended gland plate kits for DX170 and DX430 enclosures.

Gland Cable Gland plate Weidmuller part nos. Sarel part nos.

thread sizes hole size

size (mm) (mm) Gland Locknut Gland Locknut

PG9 5 to 8 15.2 951891 952216 08871 08881

PG13,5 8 to 13 20.4 951893 952218 08873 08883

WARNING
When disconnecting units for testing, take care to
segregate hazardous- and safe-area cables. Short
circuit hazardous-area cable cores to an IS earth or
insulate and secure the ends. Insulate and
secure safe-area cables. If testing 'in situ' note that
the test equipment used MUST be intrinsically safe.

Terminal Function

1 Input –ve
2 Input +ve

3 Earth leakage detection
11 Output
12 Output
13 Supply –ve
14 Supply +ve

3
2
1

6
5
4

7
8
9

10
11
12

13
14

To earth
leakage
detector

Vs
Vs+

20 to 35V dc

+



Figure 6.1: MTL5011 wiring diagram and connections

Hazardous area Safe area

12

INM5000-6 Jul 2010

6.1.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.2
and check status LEDs and relay contacts as follows:

6.2 MTL5011B single-pole changeover
relay single-channel switch/
proximity detector with line fault
detection and phase reversal

The MTL5011B is similar to the MTL5011 but with added line fault
detection (LFD) facilities.

6.2.1 Wiring connections

See figure 6.3 for wiring connections.

Note: Reactive loads must be adequately suppressed.

6.2.2 Line fault detection

(See section 3.1.4 for definition of a line fault)

Input line faults (open- or short-circuit) are indicated by an LED and the
de-energising of the output relay. LFD is enabled/disabled by a switch
located on top of the module. Note that if the LFD facility is enabled for
switch inputs, the resistors shown in figures 6.3 and 6.4 MUST be fitted.

6.2.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.4
and check the status of the output contacts as shown in table 6.1

Table 6.1

6.3 MTL5012 solid-state single-channel
switch/proximity detector with line
fault detection and phase reversal

The MTL5012 enables a safe-area load to be controlled, through a solid­state output, by a switch or proximity detector in a hazardous area. Line
fault detection (LFD) and output phase reversal (see 3.1.3) facilities are
included.

Input Phase Status Relay

switch reverse switch LED contacts

Closed Normal On Closed
Closed Reverse Off Open

Open Normal Off Open
Open Reverse On Closed

Vs
Vs+

20 to 35V dc

+



3
2
1

6
5
4

7
8
9

10
11
12

13
14

Phase Input Output Output Channel Line fault

reverse Line fault switch relay relay LED LED

switch detection (SW) (11-12) (10-11) (yellow) (red)

Normal Off a Closed Open On Off

Reverse Off a Open Closed Off Off

Reverse Off Open Closed Open On Off

Normal On Open Open Closed Off On

Normal On a Open Closed On On

Normal On b Open Closed Off Off

Normal On c Closed Open On Off

Terminal Function

1 Input –ve
2 Input +ve

3 Earth leakage detection
10 Normally-closed contact
11 Common
12 Normally-open contact
13 Supply –ve
14 Supply +ve

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

Ch1

To earth
leakage
detector

SW

Ch1

22kW

680W

a

b

c

+



Figure 6.2: Test circuit for MTL5011

Figure 6.4: Test circuit for MTL5011B

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

Outpu

To earth
leakage
detector

22kW

680W

+



Resistors required only
for line fault detection

Figure 6.3: MTL5011B wiring diagram and connections

Hazardous area Safe area

6.3.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.6
and check as shown in table 6.2

6.4 MTL5014 single-pole changeover
relay single-channel dual-output
switch/proximity detector with line
fault detection and phase reversal

The MTL5014 enables two safe-area loads to be relay-controlled by a
single hazardous-area switch or proximity detector. Phase reversal (see

3.1.3 and figure 6.8), line fault detection and slave/line fault monitoring

configurations are possible.

6.4.1 Wiring connections

See figure 6.7 for wiring connections

Note: Reactive loads must be adequately suppressed.

13

INM5000-6 Jul 2010

6.3.1 Wiring connections

See figure 6.5 for wiring connections.

6.3.2 Line fault detection

(See section 3.1.4 for definition of a line fault)

Input line faults (open- or short-circuit) are indicated by an LED and the
non-conducting of the output. LFD is enabled/disabled by a switch
located on top of the module. Note that if the LFD facility is enabled for
switch inputs, the resistors shown in figures 6.5 and 6.6 MUST be fitted.

Table 6.2

Terminal Function

1 Input –ve
2 Input +ve
3 Earth leakage detection

10 &11 Output –ve

12 Output +ve
13 Supply –ve
14 Supply +ve



+

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

To earth
leakage
detector

SW

22kW

680W

a

b

c

+



1kW

V

d

Phase Input Output Channel Line fault

reverse Line fault switch status status LED LED

switch detection (SW) (11-12) (yellow) (red)

Normal Off a Vd < 4V On Off

Reverse Off Isc= 7–9mA Vd = V

S

Off Off

Reverse Off Open Vd < 4V On Off

Normal On V

oc

= 7V5–9V5 Vd = V

S

Off On

Normal On a V

d

= V

S

Off On

Normal On c Vd < 4V On Off

Normal On b Vd = V

S

Off Off

Terminal Function

1 Input –ve
2 Input +ve
3 Earth leakage detection
7 Normally closed (output 2)
8 Common (output 2)

9 Normally open (output 2)
10 Normally closed (output 1)
11 Common (output 1)
12 Normally open (output 1)
13 Supply –ve
14 Supply +ve

Figure 6.6: Test circuit for MTL5012


+

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

To earth
leakage
detector

22kW

680W

+



Resistors required only
for line fault detection

Figure 6.5: MTL5012 wiring diagram and connections

Hazardous area

Safe area

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

To earth
leakage
detector

22kW

680W

+



Output 2

Output 1

For contact inputs
resistors must be fitted

Figure 6.7: MTL5014 wiring diagram and connections

Safe area

Hazardous area

14

INM5000-6 Jul 2010

6.4.2 Outputs

The output 1 relay reflects the status of the input and may be configured
to operate in reverse phase (PR) or with line-fault detection (LF). The
output 2 relay may be configured either to follow (slave mode) output 1
or as a line-integrity monitor (LFD) (see 6.4.3).

6.4.3 Line fault detection

(See section 3.1.4 for definition of a line fault)

Line-fault detection and the operational mode of output 2 (ie slave to
output 1 or LFD) are selected by switches located on the top of the
module (see figure 6.8).

When LFD is selected for output 2 and there is a line fault in the sensor
circuit the output 2 relay is de-energised (providing an alarm output).
When LF is selected for output 1, the output 1 relay is de-energised if
there is a line fault in the sensor circuit. Note that resistors must be fitted
when using LFD with a contact input; 500Ω to 1kΩ in series, and 20kΩ
to 25kΩ in parallel with the switch.

6.4.4 Testing

Make the relevant safe- and hazardous-area connections shown in figure

6.9 for the tests listed in table 6.3. (Figure 6.8 shows the switch positions
for configuring output 2 slave/LFD, output 1 line fault (LF) and phase
reversal (PR)).

Table 6.3

6.5 MTL5015 solid-state two-channel
switch/proximity detector with line
fault detection and phase reversal

The MTL5015 enables each of two safe-area loads to be controlled,
through a solid-state output, by a switch or proximity detector in a
hazardous area. Line fault detection (LFD) and output phase reversal
(see 3.1.3) facilities are included.

6.5.1 Wiring connections

See figure 6.10 for wiring connections.

Phase Line fault Output 1 Output 2 Status Fault

reverse detection Slave Input test switch position relay relay LED LED

Test switch (PR) (LF) (LFD) (terminals 1 & 2) (11-12) (9-8) (yellow) (red)

1 Normal Off LFD (a) i.e. short-circuit Closed Open On On

2 Reverse Off LFD (a) short-circuit (Isc=7–9mA) Open Open Off On

3 Normal On Slave (a) short-circuit Open Open Off On

4 Normal Off Slave (a) short-circuit Closed Closed On Off

5 Normal Off Slave open-circuit (Voc=7V5–9V5) Open Open Off Off

6 Normal On Slave open-circuit Open Open Off On

7 Normal Off LFD (b) 22kΩ Open Closed Off Off

8 Normal Off LFD (c) 680Ω Closed Closed On Off

LF
PR
O/P1

ON

SLAVE LFD

Output 2

MTL5014

PWR

Output 1 follows sensor

Output 2 slaves output 1

Output 1 follows sensor

Output 2 monitors LFD

Output 1 follows sensor & LFD

Output 2 slaves output 1

Output 1 follows sensor & LFD

Output 2 monitors LFD

Output 1 in phase with sensor

Output 1 in anti-phase with sensor

(LFD not affected)

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

Output 2

relay

Output 1

relay

To earth
leakage
detector

SW

22kW

680W

a

b

c

+



open

Terminal Function

1 Input –ve (Ch 1)
2 Input +ve (Ch 1)
3 Earth leakage detection
4 Input –ve (Ch 2)
5 Input +ve (Ch 2)
6 Earth leakage detection
8 Output –ve (Ch 2)

9 Output +ve (Ch 2)
11 Output –ve (Ch 1)
12 Output +ve (Ch 1)
13 Supply –ve
14 Supply +ve

6
5
4

3
2
1

7
8
9

10
11
12

13
14

To earth leakage
detector

SW

22kW

680W

a

b

c

open

22kW

+



Vs
Vs+

20 to 35V dc

} V

d2

1kW

1kW

+



+



} Vd1

Ch1

Ch2

+



Figure 6.8: Top label of MTL5014 with explanation of switch positions

Figure 6.9: Test circuit for MTL:5014

Figure 6.11: Test circuit for MTL5015

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

To earth
leakage
detector

22kW

680W

+



Resistors required only
for line fault detection

Ch 2

22kW

680W

+



Ch 1

+



+



Figure 6.10: MTL5015 wiring diagram and connections

Hazardous area Safe area

15

INM5000-6 Jul 2010

Table 6.4

6.5.2 Line fault detection

(See section 3.1.4 for definition of a line fault)

On both channels, input line faults (open- or short-circuit) are indicated
by an LED and the de-energising of the output. LFD is enabled/disabled
by switches located on top of the module. Note that if the LFD facility is
enabled for switch inputs, the resistors shown in figures 6.10 and 6.11
MUST be fitted.

6.5.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.11
and check the status of the output contacts for each channel in turn (with
a 22kΩ resistor connected to the other channel) as shown in table 6.4.

6.6 MTL5016 single-pole relay two­channel switch/proximity detector
with phase reversal (Discontinued,
use MTL5018)

The MTL5016 enables two safe-area loads to be relay-controlled by two
switches or proximity detectors located in a hazardous area. Output
phase reversal (see 3.1.3) is provided.

Table 6.5

6.6.1 Wiring connections

See figure 6.12 for wiring connections.

Note: Reactive loads must be adequately suppressed.

6.6.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.13
and check status LEDs and relay contacts as in table 6.5.

6.7 MTL5017 single-pole relay two­channel switch/proximity detector
with line fault detection and phase
reversal

The MTL5017 is similar to the MTL5018 but with the addition of line fault
detection facilities.

6.7.1 Wiring connections

See figure 6.14 for wiring connections.

Note: Reactive loads must be adequately suppressed.

6.7.2 Line fault detection

(

See section 3.1.4 for definition of a line-fault)

Line faults de-energise a dedicated line fault detect relay (between
terminals 7 and 10) to provide an alarm facility and are indicated by an
LED. Each channel relay will also de-energise (open) when a line fault
exists on that channel. LFD is automatic. Note that for switch inputs the
resistors shown in figures 6.14 and 6.15 MUST be fitted for correct LFD
operation.

Phase Input Output Channel Line fault

reverse Line fault switch status status LED LED

switch detection (SW) (11-12, 8-9) (yellow) (red)

Normal Off a Vd<4V On Off
Reverse Off a V

d

=V

S

Off Off

Reverse Off open V

d

<4V On Off

Normal On open V

d

=V

S

Off On

Normal On a V

d

=V

S

Off On

Normal On c V

d

<4V On Off

Normal On b V

d

=V

S

Off Off

Phase reverse Phase reverse Channel 1 Channel 2 Relay Relay

Input switch Input switch switch switch status LED status LED contacts contacts

(ch 1) (ch 2) (ch 1) (ch 2) (yellow) (yellow) (ch 1) (ch 2)

Closed Open Normal Normal On Off Closed Open
Closed Closed Normal Normal On On Closed Closed
Closed Closed Reverse Reverse Off Off Open Open

Open Open Reverse Reverse On On Closed Closed

Terminal Function

1 Input –ve (Ch 1)
2 Input +ve (Ch 1)
3 Earth leakage detection
4 Input –ve (Ch 2)
5 Input +ve (Ch 2)
8 Output (Ch 2)

9 Output (Ch 2)
11 Output (Ch 1)
12 Output (Ch 1)
13 Supply –ve
14 Supply +ve

3
2
1

6
5
4

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

+



SW1

SW2

Ch1

Ch2

+



Figure 6.13: Test circuit for MTL5016

3
2
1

6
5
4

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

+



To earth leakage
detector

Ch1

Ch2

Ch1

Ch2

+



Figure 6.12: MTL5016 wiring diagram and connections

Hazardous area

Safe area

16

INM5000-6 Jul 2010

6.7.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.15
and check the status of the output contacts for each channel in turn (with
a 22kΩ resistor connected to the other channel) as shown in table 6.6.

Table 6.6

6.8 MTL5018 single-pole, changeover
relay, two-channel, switch/proximity
detector with line fault detection and
phase reversal

The MTL5018 modules enable each of two safe-area loads to be relay­controlled by switches or proximity detectors in a hazardous area. Line
fault detection (LFD) and output phase reversal (see 3.1.3) facilities are
included.

6.8.1 Wiring connections

See figure 6.16 for wiring connections.

Note: Reactive loads must be adequately suppressed.

6.8.2 Line fault detection

(See section 3.1.4 for definition of a line fault)

On each channel, input line faults (open- or short-circuit) are indicated
by an LED and the de-energising of the output.

LFD is enabled/disabled by switches located on the top of the module.
Note that if the LFD facility is enabled for switch inputs, the resistors
shown in figures 6.16 and 6.17 MUST be fitted.

6.8.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.17
and check the status of the output contacts for each channel in turn (with
a 22kΩ resistor connected to the other channel) as shown in table 6.7.

6.9 MTL5018AC single-pole, changeover
relay, two-channel, switch/proximity
detector with line fault detection and
phase reversal

The MTL5018AC modules enable each of two safe-area loads to be
relay-controlled by switches or proximity detectors in a hazardous area.
Line fault detection (LFD) and output phase reversal facilities are included
(see section 3.1.3 ).

6.9.1 Wiring connections

See figure 6.18 for wiring connections.

Note: Reactive loads must be adequately suppressed.

6.9.2 Line fault detection

(See section 3.1.4 for definition of a line fault)

On each channel, input line faults (open- or short-circuit) are indicated
by an LED and the de-energising of the output. LFD is enabled/disabled
by switches located on the top of the module.

Note that if the LFD facility is enabled for switch inputs, the resistors
shown in figures 6.18 and 6.19 MUST be fitted.

Terminal Function

1 Input –ve (Ch 1)
2 Input +ve (Ch 1)
3 Earth leakage detection
4 Input –ve (Ch 2)
5 Input +ve (Ch 2)
7 Line fault detection
8 Output (Ch 2)

9 Output (Ch 2)
10 Line fault detection
11 Output (Ch 1)
12 Output (Ch 1)
13 Supply –ve
14 Supply +ve

6
5
4

3
2
1

7
8
9

10
11
12

13
14

LFD

Vs
Vs+

20 to 35V dc

Ch 2

Ch 1

LFD

LFD

To earth leakage
detector

SW

22kW

680W

a

b

c

open

22kW

+



Ch1

Ch2

+



Output Line-fault

Input relay relay

(11-12, 8-9) (7 & 10)

Open-circuit Open Open
Short-circuit Closed Open

680Ω Closed Closed

22kΩ Open Closed

Terminal Function

1 Input –ve (Ch 1)
2 Input +ve (Ch 1)
3 Earth leakage detection
4 Input –ve (Ch 2)
5 Input +ve (Ch 2)
6 Earth leakage detection
7 Normally-closed contact (Ch 2)
8 Common (Ch 2)

9 Normally-open contact (Ch 2)
10 Normally-closed contact (Ch 1)
11 Common (Ch 1)
12 Normally-open contact (Ch 1)
13 Supply –ve
14 Supply +ve

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

Ch 2

Ch 1

To earth leakage
detector

SW

22kW

680W

a

b

c

open

22kW

+



Ch1

Ch2

+



Figure 6.15: Test circuit for MTL5017

Figure 6.17: Test circuit for MTL5018

6
5
4

3
2
1

7
8
9

10
11
12

13
14

LFD

Vs
Vs+

20 to 35V dc

To earth
leakage
detector

22kW

680W

+



Ch 2

22kW

680W

+



Ch 1

LFD

LFD

For contact inputs
resistors must be fitted

Figure 6.14: MTL5017 wiring diagram and connections

Hazardous area Safe area

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

To earth leakage
detector

22kW

680W

+



22kW

680W

+



Resistors required only
for line fault detection

Ch 2

Ch 1

Figure 6.16: MTL5018 wiring diagram and connections

Hazardous area Safe area

17

INM5000-6 Jul 2010

6.9.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.19,
and check the status of the output contacts for each channel in turn (with
a 22kΩ resistor connected to the other channel) as shown in table 6.7.

6.10 MTL5021 loop-powered
solenoid/alarm driver, IIC

The MTL5021 enables a device located in the hazardous area to be
controlled by a switch located in the safe area. Suitable for IIC
applications.

610.1 Wiring connections

See figure 6.20 for wiring connections.

6.10.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.19,
apply 24V to terminals 11 and 12 and, with no load, check voltage and
short-circuit current levels at terminals 1 and 2 as follows:

Terminal Function

1 Input –ve (Ch 1)
2 Input +ve (Ch 1)
3 Earth leakage detection
4 Input –ve (Ch 2)
5 Input +ve (Ch 2)
6 Earth leakage detection
7 Normally-closed contact (Ch 2)
8 Common (Ch 2)

9 Normally-open contact (Ch 2)
10 Normally-closed contact (Ch 1)
11 Common (Ch 1)
12 Normally-open contact (Ch 1)
13 Supply N
14 Supply L

6
5
4

3
2
1

7
8
9

10
11
12

13
14

680W

22kW

22kW

To earth leakage
detector

SW

a

b

c

open

+



Ch1

Ch2

Vs

Vs

85 to 265V ac

Ch1

Ch 2

+



Phase Input Output Output Channel Line fault
reverse Line fault switch relay relay status LED LED
switch detection (SW) (11-12, 8-9) (10-11, 7-8) (yellow) (red)

Normal Off a Closed Open On Off

Reverse Off Isc= 7 – 9mA Open Closed Off Off

Reverse Off Open Closed Open Off Off

Normal On Voc= 7.5 – 9.5V Open Closed Off On

Normal On a Open Closed Off On

Normal On b Open Closed Off Off

Normal On c Closed Open On Off

Input Output Short-circuit

voltage Status voltage current

(terminals 11 & 12) LED (terminals 1 & 2) (terminals 1 & 2)

24V dc On 22 to 24V —
24V dc On — 45 to 52mA

Figure 6.19: Test circuit for MTL5018AC

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs

Ch1

Ch 2

+



22kW

22kW

680W

+



To earth
leakage
detector

Ch 1

Ch 2

680W

Hazardous area Safe area

Figure 6.18: MTL5018AC wiring diagram and connections

7
8

9
10
11
12

6
5
4
3
2
1

Solenoid, alarm or
other IS device

To earth
leakage
detector

20  35Vdc


+

+



Hazardous area

Safe area

Figure 6.20: MTL5021 wiring diagram and connections

Table 6.7

7
8

9
10
11
12

6
5

4
3
2
1

24Vdc


+

+



V

A

Figure 6.21: Test circuit for MTL5021

Terminal Function

1 Output –ve
2 Output +ve

3 Earth leakage detection
11 Supply –ve
12 Supply +ve

6.11 MTL5022 loop-powered
solenoid/alarm driver, IIB

The MTL5022 enables a device located in the hazardous area to be
controlled by a switch located in the safe area. Suitable for IIA and IIB
applications.

6.11.1 Wiring connections

See figure 6.22 for wiring connections.

6.11.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.23,
apply 24V to terminals 11 and 12 and, with no load, check voltage and
short-circuit current levels at terminals 1 and 2 as follows

18

INM5000-6 Jul 2010

6.12 MTL5023 solenoid/alarm driver with
line fault detection and phase reversal

The MTL5023 enables a device located in the hazardous area to be
controlled by a volt-free contact or logic signal located in the safe area.
Line fault detection (LFD) and output phase reversal (see 3.1.3) facilities
are included.

6.12.1 Wiring connections

See figure 6.24 for wiring connections.

6.12.2 Line fault detection

(See section 3.1.4 for definition of a line fault)

Hazardous-area line faults are signalled to the safe area by an LED and
a solid-state switch which de-energises when a line is open- or short­circuited.

6.12.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.25
and carry out the voltage and current checks as shown in table 6.8.

Input Status Output Short-circuit

voltage LED voltage current

(terminals 11 & 12) yellow (terminals 1 & 2) (terminals 1 & 2)

24V dc On 22 to 24V –
24V dc On – 61 to 70mA

Terminal Function

1 Output –ve
2 Output +ve

3 Earth leakage detection
11 Supply –ve
12 Supply +ve

7
8

9
10
11
12

6
5

4
3
2
1

24Vdc


+

+



V

A

Figure 6.23: Test circuit for MTL5022

7
8

9
10
11
12

6
5
4
3
2
1

Solenoid, alarm or
other IS device

To earth
leakage
detector

20  35Vdc


+

+



Hazardous area Safe area

Figure 6.22: MTL5022 wiring diagrm and connections

Input switch LFD Status Output Output

SW1 Phase reverse LED LED voltage current

(terminals 11 & 12) Load switch (red) (yellow) (terminals 1 & 2) (terminals 1 & 2)

Closed 2kΩ Normal Off On >19.5V –

Open 2kΩ Normal Off Off <4.5V –

Closed 15kΩ Normal On On >21.0V –

Open 15kΩ Normal On Off <7.0V –

Closed Short-circuit Normal On On – >45mA

Open Short-circuit Normal On Off – <6mA

Closed Short-circuit Reverse On Off – <6mA

Table 6.8

Vs
Vs+

20 to 35V dc

Line fault
detection

+



+



Test meter
(set initially
to volts)

Load

+



6
5
4

3
2
1

7
8
9

10
11
12

13
14

Solenoid, alarm or
other IS device

To earth
leakage
detector

+



Vs
Vs+

20 to 35V dc

Line fault
detection

+



+



6
5
4

3
2
1

7
8
9

10
11
12

13
14

Figure 6.24: MTL5023 wiring diagram and connections

Figure 6.25: Test circuit for MTL5023

Hazardous area Safe area

Terminal Function

1 Output –ve
2 Output +ve
3 Earth leakage detection

7 Line fault signal -ve
10 Line fault signal +ve
11 Control –ve
12 Control +ve
13 Supply –ve
14 Supply +ve

6.13 MTL5024 solenoid/alarm driver,
logic drive with phase reversal

The MTL5024 enables an on/off device located in a hazardous area to
be controlled by a volt-free contact or logic signal located in t he safe
area. Output phase reversal (see 3.1.3) facilities are included.

6.13.1 Wiring connections

See figure 6.26 for wiring connections.

6.13.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.27
and carry out the following output voltage and short-circuit current
checks:

6.14 MTL5025 low-current loop-powered
solenoid/alarm driver, IIC

The MTL5025 enables an on/off device located in a hazardous area to
be controlled by a switch or voltage change in a safe area.

6.14.1 Wiring connections

See figure 6.28 for wiring connections.

19

INM5000-6 Jul 2010

6.14 .2 Testing

Make the safe- and hazardous-area connections shown in figure 6.29
and carry out the following output voltage and short-circuit current
checks:

6.15 MTL5031 vibration transducer
interface

The MTL5031 repeats the signal from a vibration sensor in a hazardous
area to a monitoring system in a safe area.

6.15.1 Wiring connections

See figure 6.30 for wiring connections.

Terminal Function

1 Output –ve
2 Output +ve

3 Earth leakage detection
11 Control –ve
12 Control +ve
13 Supply –ve
14 Supply +ve

Solenoid, alarm or
other IS device

To earth
leakage
detector

+



Vs
Vs+

20 to 35V dc

+



Control

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Figure 6.26: MTL5024 wiring diagram and connections

SW1 Output Output

(terminals Phase Status voltage current

11 & 12) setting LED (terminals1 & 2) (terminals 1 & 2)

Closed Normal On 22 to 24V —

Closed Normal On — 45 to 52mA

Closed Reverse On — <6mA

Vs
Vs+

20 to 35V dc

+



+



SW1

V

A

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Figure 6.27: Test circuit for MTL5024

Safe areaHazardous area

Terminal Function

1 Output –ve
2 Output +ve

3 Earth leakage detection
11 Supply –ve
12 Supply +ve

Solenoid, alarm or
other IS device

To earth
leakage
detector

+



20 to 35V dc

+



6
5
4

3
2
1

7
8
9

10
11
12

Figure 6.28: MTL5025 wiring diagram and connections

Input voltage Status Output voltage Output current

(terminals 11 & 12) LED (terminals 1 & 2) (terminals 1 & 2)

24V On 22 to 24V –
24V On – 45 to 52mA

+



20 to 35V dc

+



V

A

6
5
4

3
2
1

7
8
9

10
11
12

Figure 6.29: Test circuit for MTL5025

Hazardous area

Safe area

Vs
Vs+

20 to 35V dc

Vibration
transducer

Common

Signal

Transducer
power V

T

Signal ve

Signal 0V

Monitor

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Figure 6.30: MTL5031 wiring diagram and connections

Hazardous area

Safe area

Terminal Function

1 Common
2 Signal
3 Transducer power V

T

11 Signal –ve
12 Signal 0V
13 Supply –ve
14 Supply +ve

20

INM5000-6 Jul 2010

6.15.2 Testing

Make the safe- and hazardous-area connection shown in figure 6.31.

Measure the voltage on terminal 3 with respect to terminal 1; this should
be >19V. Vary the potentiometer setting and check that the reading on
voltmeter V varies by no more than ±100mV.

6.16 MTL5032 pulse isolator

The MTL5032 isolates pulses from a switch, proximity detector, current
pulse transmitter or voltage pulse transmitter located in the hazardous area.

6.16.1. Wiring connections

See figure 6.32 for wiring connections.

*Note: When connected to a circuit which requires an external voltage
or current input, the output may be connected in parallel with that input
in conjunction with a pull-up resistor wired to terminal 12 and connected
to an appropriate voltage source. The zero volt of the same voltage
source should be referenced back to terminal 11. (Maximum current is
50mA; e.g. resistor value of 510Ωat 24V.)

6.16.2 Voltage pulse settings

The threshold voltage for the voltage pulse input is set by two switches
located on the base of the unit. Referring to figure 6.33, these are set
as follows:

6.16.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.34
and carry out the following checks:

O
N

2

1

OFF

ON

SW1

SW2

Label face

Base of unit

Figure 6.33: Pulse voltage selection switches

Threshold SW1 SW2

3V On On
6V On Off

12V Off Off

Vs
Vs+

20 to 35V dc

V

100W

1kW

V

T

Sig
0V

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Figure 6.31: Test circuit for MTL5031

V

Vs
Vs+

20 to 35V dc

Voltage
pulse

Current
pulse

2-wire
current
pulse

3-wire
current
pulse

3-wire
voltage
pulse



+

4/20
mA

4/20
mA

4/20
mA

6
5
4

3
2
1

7
8
9

10
11
12

13
14

+



+

+
+

Figure 6.32: MTL5032 wiring diagram and connections

Hazardous Area

Safe Area

Vs
Vs+

20 to 35V dc



+

SW1

2.2kW

2.2kW

SW2

4.7kW

TEST

6
5
4

3
2
1

7
8
9

10
11
12

13
14



+
+

Figure 6.34: Test circuit for MTL5032

Status Test LED

SW1 SW2 LED (terminal 14)

Closed Open On On

Open Closed On On

Terminal Function

1 Common -ve
2 Proximity detector +ve
3 Current +ve
4 Transmitter +ve

5 Voltage +ve
11 Output –ve
12 Output +ve
13 Supply –ve
14 Supply +ve

21

INM5000-6 Jul 2010

6.17 MTL5040 2-channel 4 to 20mA loop
isolator

The MTL5040 provides a fully floating dc supply for energising a
conventional 2-wire 4 to 20mA transmitter located in a hazardous area.
It also passes on a 4 to 20 mA or 0 to 20mA signal from a controller
located in the safe area to a load in the hazardous area.

6.17.1 Wiring connections

See figure 6.35 for wiring connections.

6.17.2 Testing

Make the safe and hazardous-area connections shown in figure 6.36
and, using RV1 to vary the output current on channel 1, and using the
current source to vary the output current on channel 2, carry out the
checks shown in table 6.9

Table 6.9

6.18 MTL5041/42 repeater power
supplies

The MTL5041/42 provide fully-floating dc supplies for energising
conventional 2-wire 4 to 20mA transmitters located in a hazardous
area. They repeat the current in another floating circuit to drive safe-area
loads. The MTL5042 also provides similar facilities for 3-wire transmitters

and permits bi-directional transmission of 'smart' digital communication
signals superimposed on the 4 to 20mA signal.

Note: MTL5042 terminals 1 and 3 only support HART® communi­cations in one direction from field device to safe-area connections 11
and 12.

6.18.1 Wiring connections

See figures 6.37 and 6.38 for wiring connections (MTL5041 and
MTL5042 respectively).

6.18.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.39
and, using RV1 to vary the output current, carry out the checks shown in
table 6.10.

7
8
9

6
5
4
3
2
1

13
14

10
11
12

I

I

I

I

4/20mA

4/20mA

P

I

Vs
Vs+

20 to 35V dc

+



+



4/20mA

Figure 6.35: MTL5040 wiring diagram and connections

Terminal Function

1 Input –ve (transmitter), ch 1
2 Input +ve (transmitter), ch 1
4 Output –ve (driver), ch 2
5 Output +ve (driver), ch 2
8 Input -ve (driver), ch 2

9 Input +ve (driver), ch 2
11 Output –ve (transmitter), ch 1
12 Output +ve (transmitter) ch 1
13 Supply –ve
14 Supply +ve

7
8
9

6
5
4
3
2
1

13
14

10
11
12

I

I

I

I

Vs
Vs+

20 to 35V dc



+

+





+

+

+



470

W

Ch 2

Current
Source

Ch 1

RV1

10kW lin

A3

A1

A4

A2

Figure 6.36: Test circuit for MTL5040

Output current Current reading Channel 1 Voltage

(A2 for Ch 1 and (A1 for Ch 1 and (terminal 2 with

A4 for Ch 2) A3 for Ch 2) respect to terminal 1)

4 to 20mA <±20μA

20mA >16.5V

Safe areaHazardous area

6
5
4
3
2
1

7
8

9
10
11
12

13
14



Vs
Vs+

20 to 35V dc

+

4/20mA

HHC*

Load

+



4/20mA

HHC*

* Hand-held communicator

I

I

Figure 6.38: MTL5042 wiring diagram and connections

Hazardous area Safe area



+

4/20mA

Vs
Vs+

20 to 35V dc

4/20mA

I

I

Load

+



6
5
4

3
2
1

7
8
9

10
11
12

13
14

Safe areaHazardous area

Figure 6.37: MTL5041 wiring diagram and connections

6
5
4

3
2
1

7
8
9

10
11
12

13
14

I

I

Vs
Vs+

20 to 35V dc

10kW lin

RV1

A1

A2



+



+

Terminal Function

1 Input –ve

2 Input +ve
11 Output –ve
12 Output +ve
13 Supply –ve
14 Supply +ve

Figure 6.39: Test circuit for MTL5041/2

Terminal Function

1 Current Input

2 Transmitter supply +ve

3 Common

4 Optional HHC -ve

5 Optional HHC +ve

8 Optional HHC -ve

9 Optional HHC +ve
11 Output –ve
12 Output +ve
13 Supply –ve
14 Supply +ve

Table 6.10

6.19 MTL5043 repeater power supply
dual output, 4 to 20mA for 2-wire
transmitters

The MTL5043 provides fully-floating dc supplies for a single
conventional 2-wire 4 to 20mA transmitter located in a hazardous area
and driving two safe-area loads. The MTL5043 design changed to
add HART functionality at the end of 2003.

6.19.1 Wiring connections (earlier non-HART version)

See figure 6.40 for wiring connections.

6.19.2 Wiring connections (HART version)

See figure 6.41 for wiring connections.

22

INM5000-6 Jul 2010

Current Current Voltage Voltage

Output reading reading (terminal 2 with respect (terminal 2 with respect
current (A1) (A1) to terminal 1) to terminal 1)

(A2) (MTL5041) (MTL5042) (MTL5041) (MTL5042)

4 to 20mA <±20µA <±10µA — —

20mA — — >16.5V >16.5V

6.19.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.42
and, using RVI to vary the output current, carry out the following checks:

6.20 MTL5044 repeater power supply

The MTL5044 provides fully-floating dc supplies for two conventional 2­wire 4 to 20mA transmitters located in a hazardous area and repeating
the current in two floating circuits to drive two safe-area loads.

6.20.1 Wiring connections

See figure 6.43 for wiring connections.

Safe area

Figure 6.40: MTL5043 wiring diagram and connections

Hazardous area

Safe area

Hazardous area

7
8
9

6
5
4
3
2
1

13
14

10
11
12

I

I

I

Vs
Vs+

20 to 35V dc

+



4/20mA



4/20mA

Load

+



4/20mA

Load

+

HHC

HHC

7
8
9

6
5
4
3
2
1

13
14

10
11
12

I

I

I

V

Vs
Vs+

20 to 35V dc

+



4/20mA



4/20mA

Load 2

+



4/20mA

Load 1

+

+



4/20mA

current

source mode

current

sink mode

Figure 6.41: MTL5043 wiring diagram and connections

Terminal Function

1 Input –ve
2 Input +ve
7 Output –ve (Ch 2 passive current sink)
8 Output –ve (Ch 2 active/+ve current sink)

9 Output +ve (Ch 2 active)
10 Output +ve (Ch 1 via 220Ω for HART apps.)
11 Output –ve (Ch 1)
12 Output +ve (Ch 1)
13 Supply –ve
14 Supply +ve

6
5
4

3
2
1

7
8

9
10
11
12

13
14

I

I

I

I

Ch 2

Ch 1

Vs
Vs+

20 to 35V dc



4/20mA

Load

+



4/20mA

Load

+

+



4/20mA

+



4/20mA

Ch 2

Ch 1

Figure 6.43: MTL5044 wiring diagram and connections

Hazardous area Safe area

Output Current Voltage
current reading terminal 2 with

(A2) (A1) respect to terminal 1)

4 to 20mA <±20µA —

20mA — >16.5V

6
5
4

3
2
1

7
8
9

10
11
12

13
14

I

I

I

Vs
Vs+

20 to 35V dc

10kW lin

RV1

A1

A2



+



+

Output 1

Output 2



+

Figure 6.42: Test circuit for MTL5043

Terminal Function

1 Input –ve (Ch 1)
2 Input +ve (Ch 1)
4 Input –ve (Ch 2)
5 Input +ve (Ch 2)
8 Output –ve (Ch 2)

9 Output +ve (Ch 2)
11 Output –ve (Ch 1)
12 Output +ve (Ch 1)
13 Supply -ve
14 Supply +ve

Terminal Function

1 Input –ve
2 Input +ve
8 Output –ve (Ch 2)

9 Output +ve (Ch 2)
11 Output –ve (Ch 1)
12 Output +ve (Ch 1)
13 Supply –ve
14 Supply +ve

6.20.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.44
and, using RV1 to vary the output current, carry out the following checks,
first on channel 1 and then on channel 2:

6.21 MTL5045/46 isolating drivers

The MTL5045/46 isolate and pass on a 4 to 20mA signal from a
controller located in a safe area to a load in a hazardous area. The
MTL5046 also permits bi-directional transmission of 'smart' digital
communication signals superimposed on the 4 to 20mA signal, and is
provided with line fault detection (LFD).

6.21.1 Wiring connections

See figures 6.45 and 6.46 for wiring connections (MTL5045 and
MTL5046 respectively).

6.21.2 Line fault detection (LFD) (MTL5046 only)

(See section 3.1.4 for definition of a line fault)

Line fault detection is signalled by an impedance change in the safe-area
loop. When a line fault occurs, the impedance between terminals 11
and 12 is >100kΩ.

6.22.1 Testing

Make the safe and hazardous-area connections shown in figure 6.47
and, using the current source to vary the output current, carry out the
checks shown in the table above figure 6.47.

6.22 MTL5048 analogue input/output, loop­powered isolator

The MTL5048 is a dual channel analogue input/output loop-powered
isolator being powered from the safe area side. The same current
flows in both hazardous and safe-area circuits and can be controlled

23

INM5000-6 Jul 2010

7
8
9

6
5
4

3
2
1

13
14

10
11
12

I

I

I

I



+



+

Ch 1

10kW lin

RV1

A1

A2

Ch 1

Ch 2

Ch 2

Vs
Vs+

20 to 35V dc



+



+

Figure 6.44: Test circuit for MTL5044

6
5
4
3
2
1

7
8

9
10
11
12

13
14



Vs
Vs+

20 to 35V dc

+

4/20mA

P

I

4/20mA

+



I

I

Hazardous area

Safe area

Figure 6.45: MTL5045 wiring diagram and connections

Hazardous area

Safe area

6
5
4
3
2
1

7

8

9
10
11
12

13
14



Vs
Vs+

20 to 35V dc

+

4/20mA

HHC*

HHC*

* Hand-held communicator

P

I

4/20mA

+



I

I

Hazardous area

Safe area

Figure 6.46: MTL5046 wiring diagram and connections

Output Current Voltage channel 1 Voltage channel 2
current reading (terminal 2 with (terminal 5 with

(A2) (A1) respect to terminal 1) respect to terminal 4)

4 to 20mA <±20µA – –

20ma – >16.5V –

20ma – – >16.5V

Output Current reading Current reading
current (A1) (A1)

(A2) (MTL5045) (MTL5046)

4 to 20mA <±20µA <±10µA

6
5
4
3
2
1

7
8

9
10
11
12

13
14

I

I

Vs
Vs+

20 to 35V dc

+

A1

A2



+



Current
source

680W

+

Figure 6.47: Test circuit for MTL5045/46

Terminal Function

1 Output –ve
2 Output +ve
4 Optional HHC -ve
5 Optional HHC +ve
8 Optional HHC -ve

9 Optional HHC +ve
11 Input –ve
12 Input +ve
13 Supply –ve
14 Supply +ve

6
5
4

3
2
1

7
8
9

10
11
12

I

I

I

I

Ch 2

+



Ch 1

+



22
35V
dc

Ch 2

Ch 1

+



4/20mA

4/20mA

HHC

HHC

4/20

+



HHC

HHC

P

I

P

I

4/20

22
35V
dc

Figure 6.48: MTL5048 wiring diagram and connections

Terminal Function

1 Tx– or input connection –ve (Ch 1)
2 Tx+ or input connection +ve (Ch 1)
4 Tx– or input connection –ve (Ch 2)
5 Tx+ or input connection +ve (Ch 2)
8 Output –ve or input +ve (Ch 2)

9 Output +ve or Tx supply +ve (Ch 2)
11 Output –ve or input +ve (Ch 1)
12 Output +ve or Tx supply +ve (Ch 1)

Terminal Function

1 Output –ve

2 Output +ve
11 Input –ve
12 Input +ve
13 Supply –ve
14 Supply +ve

6.24 MTL5051 serial data comms isolator

The MTL5051provides either bi-directional serial data communications
from a computer system in a safe area to instrumentation in a hazardous
area or data communications across a hazardous area. It is used to
provide a fully floating dc supply for, and serial data communications to
MTL640 text displays and MTL650 series text and graphics terminals or
to other IS and non-IS instrumentation and keyboards.

6.24 .1 Wiring connections

See figures 6.52 and 6.53 and the terminal specifications in tables 6.11
and 6.12 for wiring connections. See also section 6.22.2 on hazardous­area interfacing.

6.24.2 Hazardous-area interfacing
Displays/terminals: For details of interfacing with MTL640 and

MTL650 series displays/terminals (as an alternative to the MTL696
communications interface) see the appropriate product instruction
manual.

24

INM5000-6 Jul 2010

from either. For smart two–wire transmitters it provides bi-directional
communication signals superimposed on the 4/20mA signal. The
MTL5048 can also be used for isolating and passing a 4/20mA
signal from the safe area to the hazardous-area. The transmitter can
be interrogated either from the operator station or by a hand-held
communicator (HHC) for both the channels.The MTL5049 isolates and
passes on two 4 to 20mA signals from a controller located in a safe area
to two loads in a hazardous area.

6.22.1 Wiring connections

See figure 6.48 for wiring connections.

6.22.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.49
and, using RV1 to vary the output current, carry out the following checks,
first on channel 1 and then on channel 2.

6.23 MTL5049 two-channel isolating driver

The MTL5049 isolates and passes on two 4 to 20mA signals from a
controller located in a safe area to two loads in a hazardous area.

6.23.1 Wiring connections

See figure 6.50 for wiring connections.

6.23.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.51
and, using the current source to vary the output current, carry out the
following checks, first on channel 1 and then on channel 2.

6

5

4

3

2

1

7

8

9

10

11

12

13

14

Vs

Vs+

20 to 35V dc

RS232, TTL
or RS422

Rx
Tx

5V or 12V supply
Common

Tx
Rx

Supply
Common

Figure 6.52: MTL5051 wiring diagram (to a hazardous area)

Hazardous area Safe area

Output Current
current reading (A1)

4 to 20mA <±20μA

6
5
4

3
2
1

7
8

9
10
11
12

13
14

I

I

I

I

Vs
Vs+

20 to 35V dc

A1

A2



+

Current
source

470W

+



+



+

Ch1

Ch2

Ch1

Ch2

Figure 6.51: Test circuit for MTL5049

RS232, or
RS422

RS232, or
RS422

6
5
4
3
2
1

7
8

9
10
11
12

13
14

6
5
4
3
2
1

7

8

9
10
11
12

13
14

Vs
Vs+

20 to 35V dc

Vs
Vs+

20 to 35V dc

Safe area

Hazardous area

Figure 6.53: MTL5051 wiring diagram (across a hazardous area)

Output Current

current (A2) reading (A1)

4 to 20mA <±80μA

6
5
4

3
2
1

7
8

9
10
11
12

13
14

I

I

I

I

P

I

4/20mA

+



P

I

4/20mA

+





+

4/20mA



+

4/20mA

Vs
Vs+

20 to 35V dc

Ch 1

Ch 2

Ch 1

Ch 2

Figure 6.50: MTL5049 wiring diagram and connections

Hazardous area Safe area

Terminal Function

1 Output –ve (Ch 1)
2 Output +ve (Ch 1)
4 Output -ve (Ch 2)
5 Output +ve (Ch 2)
8 Input -ve (Ch 2)

9 Input +ve (Ch 2)
11 Input –ve (Ch 1)
12 Input +ve (Ch 1)
13 Supply –ve
14 Supply +ve

6
5
4

3
2
1

7
8

9

10
11
12

I

I

I

I

Ch 2

+



+



Ch 2

24V

+



A1

A2

Ch 1

180W

2k

RV1

W

+



+



240W

Figure 6.49: Test circuit for MTL5048

6.24.3 Testing

Remove all safe- and hazardous-area connections and apply 24V dc to
terminals 13 and 14 as shown in figure 6.55. Check that the green
power LED (on top of the unit) is on. Put all switches in the On position.
With no load, check for nominal current of 60mA ±5mA at terminal 14.
Correct operation of the communication modes is indicated by signals
received and/or transmitted.

6.25 MTL5053 isolator/power supply for

31.25kbit/s fieldbuses

The MTL5053 has been specifically developed to extend 31.25kbit/s
(H1) fieldbus networks into hazardous areas. It provides power,
communication and IS isolation to devices powered through the signal
conductors. The MTL5053 complies with the requirements of Fieldbus
Foundation™ specified power supply Type 133 (IS power supply).

To comply with fieldbus standards, each bus must be terminated at both
ends. MTL's FBT1-IS or FCS-MBT fieldbus terminators (see section 6.33)
can be supplied for this purpose or, for installations in which the safe­area bus length is small, the MTL5053 includes an internal safe-area
terminator which is enabled by a switch located on the top of the unit.

For network and termination criteria, check applicable fieldbus
standards and specification

IEC 61158-2, ISA-S50.02 for 31.25kbit/s
fieldbus systems, Foundation™ Fieldbus 31.25kbit/s Physical Layer
Profile Specification FF-816

and MTL's Application Brief AB002.)

6.25.1 Wiring connections

See figure 6.56 for wiring connections and refer to MTL's Application
Brief AB002.

Note: To assist the process of terminating cable screens,
screw terminals have been provided in terminal positions 3 and 6 and
7 and 10. Please note, however, that there is no internal connection for
these terminals so they are not earthed.

25

INM5000-6 Jul 2010

Across hazardous areas: For communication across hazardous

areas MTL5051 devices are used in pairs to transfer bi-directional full­duplex data across hazardous areas, as shown in figure 6.53. Current
switching is used to minimise the bandwidth-limiting effects of long cables.

The maximum baud rate in this mode is the lesser of 19.2k baud or the
cable-related rate produced by the following formula.

Remote signalling baud rate formula, for back-to-back mode across a
hazardous area:

max baud rate = K/(RxCxL

2

)

where K = 0.25 (constant)

R = cable resistance (Ω/m)
C = cable capacitance (F/m)
L = length (m)

For example, with a 2km cable of 100pF/m capacitance and 40mΩ/m
resistance, the maximum baud rate = 0.25/(40mΩ x 100pFx 2km

2

) =
15k baud. This assumes that the cable is 2 cores plus screen, with the
screen used for the 'common' connection.

RS232-level devices: Communication with RS232-level interfaces, such
as a suitably certified IS keyboard, mouse, etc, is achieved by using one
or more MTL5051 units as required by the IS device.(TTL level interfaces
are accommodated by the TTL compatibility of RS232 receivers.)

The supply to IS equipment at terminal 2 can be set to either 5V or
12V, by a switch located on top of the unit, as follows:

+12V mode 12.0V ±5% (load <23mA)
+12V mode 8.0V min (load >23mA to <50mA)
+5V mode5.6V ±5% (load >23mA to <50mA)

Note: the normal RS232 limitations of bandwidth versus cable length are
applicable. As a rule of thumb, speed (baud) x length (metres) <150,000.

6
5
4

3
2
1

7
8

9
10
11
12

13
14

dc supply


+

Figure 6.55: Test circuit for MTL5051

Terminal Function

1 Hazardous-area fieldbus device(s) connection –ve
2 Hazardous-area fieldbus device(s) connection +ve
4 Optional HHC connection –ve

5 Optional HHC connection +ve
8 & 11 Safe-area fieldbus device(s) connection –ve
9 & 12 Safe-area fieldbus device(s) connection +ve

13 Supply –ve
14 Supply +ve

FBT1
fieldbus
terminator

**

6
5
4

3
2
1

7
8

9
10
11
12

13
14

T

*Hand-held communicator
** See section 6.33 for details of FBT1

T

Vs+

Vs

20 to 35V dc

HHC*

Fieldbus
devices

T

FBT1
fieldbus
terminator

**

+



+



devices

Fieldbus
devices

Figure 6.56: MTL5053 wiring diagram and connections

Hazardous area Safe area

2a
2b

ON

MTL5051

PWR

1a
1b

Figure 6.54: Top label, MTL5051

Table 6.11 (see also figure 6.54)

Table 6.12 (see also figure 6.52)

MTL5051 MTL640 MTL650 Comms Other IS

Terminals mode mode mode devices

1 Common Common Common Common
2 V signal 12V - 5V/12V
3 I return Rx Rx ­4 - Tx Tx ­5---Tx

6---Rx

Switch

1a On Off Off Off
1b On On On Off/On

Terminals RS232 mode TTL mode RS422 mode

7 - - Rx ­8 - - Rx+
9 - Tx Tx+

10 Tx - Tx­11 Common Common Common
12 Rx Rx ­13 Supply -ve Supply -ve Supply -ve
14 Supply +ve Supply +ve Supply +v

Switch

2a Off On On
2b On Off Off

26

INM5000-6 Jul 2010

6.25.2 Testing

Make the safe and hazardous-area connections shown in figure 6.56
and, substituting appropriate resistors at R

test

, carry out the following

checks.

6.26 MTL5061 two-channel loop-powered
fire/smoke detector interface

The MTL5061 isolates two conventional fire and smoke detectors located
in hazardous areas. The triggering of a detector causes a
corresponding change in the safe-area circuit. The unit has reverse input
polarity, and 'non-fail' earth fault detection on either line can be
provided.

6.26.1 Wiring connections

See figure 6.59 for wiring connections.

6.26.2 'No-fail' earth fault protection

Protection is enabled by connecting earth leakage detectors, such as
MTL2220s (not CE marked), to the MTL5061; via terminal 3 or 6, or
both. To maintain isolation between the two channels, separate earth
leakage detectors are required. If a fault on either line of each channel
is detected, the unit continues working.

Note: The MTL2220 introduces a 100µA, 1Hz ripple to the field circuit.

6.26.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.60
and, using RV1 to vary the output current, carry out the following check
for both channel 1 and channel 2:

6.27 MTL5074 temperature converters,
THC or RTD input

The MTL5074 converts low-level signals from temperature sensors
located in a hazardous area into 4 to 20mA signals for driving safe-area
loads.

Note: The earlier model MTL5073 had an internal link between
terminals 11 and 13. The MTL5073 model is discontinued.

6.27.1 Wiring connections

See figure 6.61 for wiring connections.

Note: for THC inputs requiring cold-junction compensation, a HAZ-CJC
hazardous-area connector (with integrated CJC sensor) is required not a
HAZ1-3 signal plug.

6
5
4

3
2
1

7
8

9

10
11
12

I

I

I

I

Ch 2

Fire detectors

+



To earth leakage
detector

Ch 1

Fire detectors

+



6 to
35V dc

6 to
35V dc

Ch 2

Ch 1

+



+



Figure 6.59: MTL5061 wiring diagram and connections

Hazardous area Safe area

Output Current
current reading

(A2) (A1)

10 to 40mA <±400µA

6
5
4

3
2
1

7
8

9

10
11
12

I

I

I

I

Ch 2

+



+



Ch 2

24V

+



A1

A2

Ch 1

180W

2k

RV1

W

+



+



Figure 6.60: Test circuit for MTL5061

Hazardous area Safe area

Figure 6.61: MTL5073/74 wiring diagram

7
8
9

10
11
12

13
14

6
5
4

3
2
1

mV

I

Vs
Vs+

20 to 35V dc

+



mV

Load

4-wire
3-wire



+

4/20mA

MTL5053

PWR

TERMINATOR

Figure 6.58: Top label, MTL5053

Voltage across

R

test

terminals 2 and 1 (V1)

Open-circuit 17.8 < V

1

<19V

220Ω 11.5V <V1<13.5V

10Ω V

1

<5V

6
5
4

3
2
1

7
8

9
10
11
12

13
14

T

V

V

Vs+

Vs

20 to 35V dc

R

test

V

1

+



Figure 6.57 : Test circuit for MTL5053

Terminal Function

1 THC/EMF/RTD input –ve
3 THC/EMF/RTD input +ve
4 3-wire RTD input –ve

5 4-wire RTD input +ve
11 Output –ve
12 Output +ve
13 Supply –ve
14 Supply +ve

Terminal Function

1 Output –ve (Ch 1)
2 Output +ve (Ch 1)
3 Earth leakage detection (Ch 1)
4 Output –ve (Ch 2)
5 Output +ve (Ch 2)
6 Earth leakage detection (Ch 2)
8 Input –ve (Ch 2)

9 Input +ve (Ch 2)
11 Input –ve (Ch 1)
12 Input +ve (Ch 1)

A switch located on top of the module enables or disables a safety drive
in the event of thermocouple burnout or cable breakage; a second
switch permits the selection of upscale or downscale drive as required.

6.28.1 Safety drive

Please note that the safety drive on the MTL5081 responds to line
breakage (an open circuit) or in the event of thermocouple burnout. It
does not provide detection of a short circuit. It can, however, be set
upscale or downscale. Selection is made by switches located on top of
the module (see figure 6.64)

* Note that the above statement Vout = Vin is subject to transfer accuracy
and drift specified in the MTL Intrinsic Safety catalogue.

6.28.2 Wiring connections

See figure 6.65 for wiring connections.

27

INM5000-6 Jul 2010

6.27.2 Testing

Default parameters for the MTL5074, unless custom configured by MTL,
are:

Input type 3-wire RTD
Linearisation enabled
Units °C
Cj compensation disabled
Damping value 0 sec
Smoothing value 0 sec
Output zero 0°C
Output span 250°C
Tag and description fields clear
Open circuit alarm high
Transmitter failure alarm low
Cj failure alarm low
Line frequency 50Hz

Note: the configuration of MTL5074 cannot be changed without the aid

of a PCS/PCL45 configurator (see INM073A Connection and
Configuration Manual for full details). These devices also enable more
comprehensive testing of the converters.

Make the safe- and hazardous-area connections shown in figure 6.62.
Note that the range of the dc ammeter 'A' must be suitable for 4 to
20mA currents and the variable resistor 'R' should have a range of 0­200Ω and, ideally, should be a decade resistance box. Switch on the
power supply and check that the green power LED comes on (if it flashes,
the unit is incorrectly configured or the test wiring setup is faulty). Check
that the loop output current at 'A' varies as the variable resistance at 'R'
is altered and check the table below for particular settings (194Ω
@250°C and 100Ω @0°C for a PT100 sensor).

6.28 MTL5081 millivolt isolator

The MTL5081 takes a low level dc signal from a voltage source in a
hazardous area, isolates it and passes it to a receiving instrument
located in the safe area. Although used with thermocouples, this unit
does not have cold junction compensation facility. It is intended for use
with thermocouples utilising external cold junction compensation. When
using with thermocouples, in order to minim ise the temperature gradient
between the safe- and hazardous-area terminals, it is recommended that
the units are mounted on vertical DIN rail (see figure 6.63).

Input Loop output Power

resistance current LED

(R) (A) (green)

194Ω 20mA On
100Ω 4mA On

Open circuit 22.25mA Flashing

Short circuit 22.25mA Flashing

7
8
9

10
11
12

13
14

6
5
4

3
2
1

mV

I

20 to 35V dc

Note: The MTL5073 (which is no longer manufactured)
had an internal link between terminals 11 and 13.

Vs
Vs+



+

Loop output
4 to 20mA

A

+



VR1

200W lin

Figure 6.62: Test circuit for MTL5074

Figure 6.63: MTL5000 Series units mounted on vertical DIN rail

ON

MTL5081

PWR

LF
PR
CH1

ON

OFF

+

SAFETY

DRIVE

SAFETY DRIVE LINE

ON/OFF +/- BREAKAGE Vout

OFF N/A NO Vin*
OFF N/A YES undetermined
ON + NO Vin*
ON + YES >+100mV
ON – NO Vin*
ON – YES <–100mV

Figure 6.64: Top label of MTL5081 showing positions of
safety drive switches and an explanation of their functions

Terminal Function

1 THC/mV input –ve

2 THC/mV input +ve
11 Output –ve
12 Output +ve
13 Supply –ve
14 Supply +ve

7
8
9

6
5
4
3
2
1

13
14

10
11
12

mV

mV

Vs+

Output

Vs

20 to 35V dc

mV



+



+

Figure 6.65: MTL5081wiring diagram and connections

Hazardous area

Safe area

INM5000-6 Jul 2010

6.29.1 Input mode selection

The unit is factory set for 3-wire RTD mode. To select 2-wire or 4-wire RTD
modes, configure the switches located on the top of the unit in
accordance with the diagrams in figure 6.68.

6.29.2 Wiring connections
Warning: Check polarity of terminals used for safe-area connections.

Safe-area terminals 9, 10, 11 and 12 are unipolar so it is essential to
select a positive terminal on the MTL5082 for connection to the positive
of the RTD input card.

See figure 6.67 for wiring connections.

6.29.3 Testing

Make the safe- and hazardous-side connections shown in figure 6.69,
ensuring that the configuration switches on top of the unit are set to 3­wire RTD input mode (see figure 6.68). Carry out the following tests and
checks using a resistance box, with a range of 0 to 400Ω, and a
voltmeter, covering the range 47.0mV to 2.100V.

1. Set the resistance box to any value in the range 10Ω to 400Ω,
switch on the power supply and check that the green power
(PWR) LED comes on and remains steady. If the LED is flashing
after 5 seconds, either the test-wiring set-up is faulty or the unit is
faulty.

2. Check that the output voltage changes as the input resistance is
varied within the range 10Ω to 400Ω.

3. Short circuit the input and check that the output voltage is
≤51.6mV after 5 seconds.

4. Open circuit the input and check that the output voltage is
≤2.071V after 5 seconds and that the green PWR LED is flashing.

5. Set the input resistance to 200Ω and check that the output
voltage settles to 1.0V ±32mV.

6.30 MTL5099 dummy isolator

The MTL5099 is used with other MTL5000 Series units to provide
termination and earthing facilities for unused cable cores from
hazardous areas.

6.30.1 Wiring connections

See figure 6.70 for wiring connections.

6.28.3 Testing

Make the safe and hazardous-area connections shown in figure 6.66

Note: A millivoltmeter capable of measuring to within 1µV should be
used for V1.

Carry out the checks shown in table 6.13, using RV1 to vary the output
at V2 for the first test.

Table 6.13

6.29 MTL5082 resistance isolator

The MTL5082 connects to a 2-, 3- or 4-wire resistance temperature
device (RTD) or other resistance located in a hazardous area, isolates it
and repeats the resistance to a monitoring system in the safe area. The
module drives upscale in the case of open circuit detection. The number
of wires which can be connected on the safe-area side of the unit is
independent of the number of wires connected on the hazardous-area
side.

The module is intended typically, but not exclusively, for use with Pt100 3­wire RTDs. Switches located on top of the module allow selection of 2-, 3­or 4-wire connection. The MTL5082 is also used as an alternative, non­configurable MTL5074, for use in RTD applications where a resistance
input is preferred or needed instead of 4 to 20mA.

2

4

3

4

2

3

MTL5082

PWR

WIRE

Switch positions

4-wire 2-wire 3-wire

Figure 6.68: Top label, MTL5082, showing positions of
configuration switches and switch-position configurations for
different input modes

SAFETY DRIVE

ON/OFF +/- LINK V1 V2

OFF N/A CLOSED <0.05mV 0 ≤ V2 ≤ 50 mV
ON + OPEN N/A > +100 mV
ON - OPEN N/A < -100 mV

+



4-wire
3-wire
2-wire

7
8
9

6
5
4
3
2
1

13
14

10
11
12

W

W



+



+

Vs+

Vs

20 to 35V dc

Figure 6.67: MTL5082 wiring diagram and connections

Hazardous area Safe area

7
8
9

6
5
4
3
2
1

13
14

10
11
12

W

W

Vs+

Vs

20 to 35V dc

V

Voltmeter



+



+

Current Source

5.0mA ± 150µA

4-wire
3-wire
2-wire

+



Resistance

box

Figure 6.69: Test circuit for MTL5082

28

Terminal Function

1 RTD input –ve
3 RTD input +ve
4 3-wire RTD input –ve
5 4-wire RTD input +ve

9 RTD output –ve
10 RTD output +ve
11 RTD output –ve
12 RTD output +ve
13 Supply –ve
14 Supply +ve

7
8
9

6
5
4
3
2
1

13
14

10
11
12

mV

mV

Vs+

+

+



Vs

20 to 35V dc

39kW

RV1

100W



V1

V2

Figure 6.66: Test circuit for MTL5081

6.31 MTL5113P fail-safe switch/proximity
detector interface

With the MTL5113P, a fail-safe switch/proximity detector located in the
hazardous area can control an isolated, fail-safe electronic output. The
MTL5113P unit also provides line-fault detection alarm contacts.

The MTL5113P is for use with P + F TÜV-approved fail-safe sensors.
Correct operation of fail-safe output and LFD, where applicable, is

indicated by amber and red LEDs on top of the unit. Amber is ON
when fail-safe output is energised. Red is ON if a line fault is detected.
Fail-safe output is OFF if the incorrect sensor current, an open circuit
or a short circuit is present in the sensor circuit.

MTL5113P input/output characteristics are shown in table 6.14.

Table 6.14

6.31.1 Wiring connections

See figure 6.71 For wiring connections.

Note: Switch-type sensors must always be fitted with resistors, as shown.

*

Series resistor should be in the range 1k3Ω- 1k5

Ω

6.31.2 Line fault detection

(See section 3.1.4 for definition of a line fault

)

If an input line fault (open- or short-circuit) is detected, a red LED on top
of the unit goes ON, the LFD contacts open and the LFD output is de­energised providing an alarm output. The fail-safe output is also de­energised and the amber output status LED on top of the unit goes OFF.

29

INM5000-6 Jul 2010

6.31.3 Testing

Make the safe- and hazardous-side connections shown in figure 6.72.
With an ohmmeter, check that the status of the outputs is as follows:

6.32 MTL5314 trip amplifier for 2– or 3– 2
wire transmitters

The MTL5314 connects to a 2– or 3– wire 4 to 2mA transmitter or
current source located in the hazardous area. It supplies one or two
configurable alarm signals to the safe area via changeover relays.
Each relay may be configured individually to signal an alarm condition
when the input signal is greater than or less than a pre-set value.

In addition, the MTL5314 can be connected in series to the hazardous­area side of an MTL5042 4 to 20mA repeater power supply (or equivalent
device) to provide two trip alarm outputs direct from the transmitter signal
(see schematic diagram). Looping the transmitter signal through the MTL
5314 (via terminals 1 and 3) does not affect HART® communications.
Terminals 1 and 3 meet clause 5.4 of EN50020: 1994 and have the
following parameters: U ≤ 1.5V, I ≤ 0.1A, P ≤ 25mW. They can be
connected without further certification into an IS loop with open circuit
voltage of not more than 28V. See certificate for further details.

6.32.1 Wiring connections

See figure 6.73 for wiring connections.
If terminals 1 and 3 provide a 4 to 20mA loop to a HART transmitter,

HART communication can be superimposed on the 4 to 20mA signal.

Note: Reactive loads must be adequately suppressed

.

Unused
hazardous­area cores

3
2
1

6
5
4

7
8
9

10
11
12

13
14

Unused
safe-area
cores

Figure 6.70: MTL5099 wiring diagram and connections

Hazardous area Safe area

Input value in Fail-safe Operation LFD contacts
sensor circuit output

2.9mA < Is < 3.9mA ON Normal Closed

Is<1.9mA and Is>5.1mA OFF Normal Closed

Is<50µA OFF Broken line Open

Is>66mA OFF Shorted line Open

Terminal Function

1 Input –ve
2 Input +ve
3 Output –ve

7 Output +ve
10 LFD
11 LFD
13 Supply –ve
14 Supply +ve

Figure 6.71: MTL5113P wiring diagram and connections

Hazardous area Safe area

Input Fail-safe Line fault

output contacts output

open-circuit de-energised open de-energised
short-circuit de-energised open de-energised
1k4Ω energised closed energised
10kΩ de-energised closed energised

6
5
4

3
2
1

7
8
9

10
11
12

13
14

+



+



Failsafe
output

LFD

Vs
Vs+

20 to 35V dc

SW

1k4W
10kW

Figure 6.72: Test circuit for MTL5113P

Terminal Function

1 Hazardous-area core
2 Hazardous-area core
3 Hazardous-area core
4 Hazardous-area core
5 Hazardous-area core
6 Earth
7 Safe-area core
8 Safe-area core

9 Safe-area core
10 Safe-area core
11 Safe-area core
12 Safe-area core

6
5
4

3
2
1

7
8
9

10
11
12

13
14

+



+



Failsafe
output

LFD

Vs
Vs+

20 to 35V dc

1k4W*

10kW

Resistors are required
for switch inputs

30

INM5000-6 Jul 2010

6.32.2 Trip calibration

Switches and multiturn potentiometers for setting the trip points are
located on top of the unit (see figure 6.74). For each of channels A and
B:

i Set trip switch to H (high) or L (low) as required (see table 6.15

for relay operation).
ii Set input current to the required value for trip-point.
iii Adjust SET A/SET B until LED A/B is on: then slowly adjust until

LED goes out.
iv Relays are energised in normal operation and de-energised when

tripped. A lit LED shows the safe condition (not tripped).

Table 6.15

– = Either option ✫ = LED On • = LED Off

6.32.3 Testing

Make the safe- and hazardous-area connections shown in figure 6.75
and carry out the following procedure:

a Set the current source or sink to 12mA
b Adjust each trip potentiometer until the associated LED just

extinguishes.

c With sources of 11.5mA and 12.5mA carry out the following

checks:

6
5
4

3
2
1

7
8
9

10
11
12

13
14

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

Trip B

Trip A

Vs
Vs+

20 to 35V dc

+

4/20mA

Load

+



4/20mA

* Hand-held communicator

6
5
4
3
2
1

7
8

9
10
11
12

13
14

I

I



Vs
Vs+

20 to 35V dc

Trip B

Trip A

+



HHC*

HHC*

+

4/20mA



4/20mA

+



+



MTL5314

MTL5042

MTL5314

Figure 6.73: MTL5314 wiring diagram and connections

Terminal Function

1 Current input
2 Transmitter supply +ve
3 Common
7 Trip B (NC)
8 Trip B (COM)

9 Trip B (NO)
10 Trip A (NC)
11 Trip A (COM)
12 Trip A (NO)
13 Supply –ve
14 Supply +ve

Hazardous area

Safe area

H
H

SET

A

MTL5314

PWR

LF
PR
CH1

ON

L
L

SET

B

A B

Figure 6.74: Top label, MTL5314, showing positions of trip
switches and multiturn potentiometers

Trip Operation PWR A or B Relay contacts
switch LED LED 11-12 10-11
A or B 8-9 7-8

H (high) Input >Trip setting ✫ • open closed
H (high) Input <Trip setting ✫✫closed open

L (low) Input >Trip setting ✫✫closed open
L (low) Input <Trip setting ✫ • open closed

– – • • open closed

6
5
4

3
2
1

7
8
9

10
11
12

13
14

Vs
Vs+

20 to 35V dc

Trip B

Trip A

Source

or

sink

I

I

+



High alarm Low alarm

Relay Relay

LED 11-12 10-11 LED 11-12 10 -11

Current 8 - 9 7 - 8 8 - 9 7 - 8

11.5mA On Closed Open Off Open Closed

12.5mA Off Open Closed On Closed Open

Figure 6.75: Test circuit for MTL5314

31

INM5000-6 Jul 2010

6.33 MTL5344 Repeater power supply

The MTL5344 provides fully-floating dc supplies for two conventional 2­wire 4 to 20mA transmitters located in a hazardous area and repeats
the current in two floating circuits to drive two safe-area loads.

Note that although this module is similar in function to the MTL5044, the
safety description parameter are very different. Refer to the datasheet
and the ATEX certificate available from the MTL website.

6.33.1 Wiring connections

See figure 6.76 for wiring connections.

6.33.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.77
and, using RV1 to vary the output current, carry out the following checks,
first on channel 1 and then on channel 2:

6
5
4

3
2
1

7
8

9
10
11
12

13
14

I

I

I

I

Ch 2

Ch 1

Vs
Vs+

20 to 35V dc



4/20mA

Load

+



4/20mA

Load

+

+



4/20mA

+



4/20mA

Ch 2

Ch 1

Figure 6.76: MTL5344 wiring diagram and connections

Hazardous area Safe area

Terminal Function

1 Input –ve (Ch 1)
2 Input +ve (Ch 1)
4 Input –ve (Ch 2)
5 Input +ve (Ch 2)
8 Output –ve (Ch 2)

9 Output +ve (Ch 2)
11 Output –ve (Ch 1)
12 Output +ve (Ch 1)
13 Supply -ve
14 Supply +ve

7
8
9

6
5
4

3
2
1

13
14

10
11
12

I

I

I

I



+



+

Ch 1

10k

W

lin

RV1

A1

A2

Ch 1

Ch 2

Ch 2

Vs
Vs+

20 to 35V dc



+



+

Figure 6.77: Test circuit for MTL5344

Output Current Voltage channel 1 Voltage channel 2
current reading (terminal 2 with (terminal 5 with

(A2) (A1) respect to terminal 1) respect to terminal 4)

4 to 20mA <±20µA – –

20ma – >14V –

20ma – – >14V

6.34 MTL5349 two-channel isolating driver

The MTL5349 isolates and passes on two 4 to 20mA signals from a
controller located in a safe area to two loads in a hazardous area.

Note that although this module is similar in function to the MTL5049, the
safety description parameter are very different. Refer to the datasheet
and the ATEX certificate available from the MTL website.

6.34.1 Wiring connections

See figure 6.78 for wiring connections.

6.34.2 Testing

Make the safe- and hazardous-area connections shown in figure 6.79
and, using the current source to vary the output current, carry out the
following checks, first on channel 1 and then on channel 2.

6
5
4

3
2
1

7
8

9
10
11
12

13
14

I

I

I

I

P

I

4/20mA

+



P

I

4/20mA

+





+

4/20mA



+

4/20mA

Vs
Vs+

20 to 35V dc

Ch 1

Ch 2

Ch 1

Ch 2

Figure 6.78: MTL5349 wiring diagram and connections

Hazardous area Safe area

Terminal Function

1 Output –ve (Ch 1)
2 Output +ve (Ch 1)
4 Output -ve (Ch 2)
5 Output +ve (Ch 2)
8 Input -ve (Ch 2)

9 Input +ve (Ch 2)
11 Input –ve (Ch 1)
12 Input +ve (Ch 1)
13 Supply –ve
14 Supply +ve

Output Current
current reading (A1)

4 to 20mA <±20μA

6
5
4

3
2
1

7
8

9
10
11
12

13
14

I

I

I

I

Vs
Vs+

20 to 35V dc

A1

A2



+

Current
source

470W

+



+



+

Ch1

Ch2

Ch1

Ch2

Figure 6.79: Test circuit for MTL5349

6.35 MTL5991 24V dc power supply

The MTL5991 provides a convenient source of power for MTL5000
Series units in locations where a dc supply is not readily available. The
2A capability at 24V dc is sufficient to drive at least fifteen (15)
MTL5000 Series modules, or more in appropriate combinations (see
table 6.16), and the wide mains power supply range makes this unit
universally applicable.

Table 6.16

Note:The maximum current drawn from the load unit is taken at 24V.
The maximum current drawn from the MTL5991 was taken to be 1.6A

6.35.1 Wiring connections

See figure 6.80 for wiring connections.

32

INM5000-6 Jul 2010

Current

MTL5000 unit Drawn mA Maximum

(Vs=24V) number of units

MTL5011B 35 46
MTL5012 30 53
MTL5014 45 36
MTL5015 44 36
MTL5017 50 32
MTL5018 60 27
MTL5023 100 16
MTL5024 100 16
MTL5031 80 20
MTL5032 65 25
MTL5040 95 17
MTL5041 70 23
MTL5042 75 21
MTL5044 110 15
MTL5045 50 32
MTL5046 65 25
MTL5048 40 35
MTL5049 65 25
MTL5051 90 18
MTL5074 68 24
MTL5081 20 80
MTL5082 55 29
MTL5113P 70 23
MTL5314 85 19
MTL5344 122 13
MTL5349 67 24

WARNING

Segregation between hazardous- and safe-area wiring
must always be maintained

4

5

6

7
8

+



1

2

3

Figure 6.80: MTL5991 wiring diagram and connections

Terminal Function

1 AC Line
2 Earth
3 AC neutral
4 +24V
5 +24V
6OV
7OV
8 Do not use

Safe area

6.35.2 Testing

Using the terminal assignments shown in figure 6.81, make the following
tests and checks.

1. Connect a supply voltage of between 85V and 264V ac to the
live and neutral terminals. Check that the voltage measured
across these terminals is within the range 85V to 264V ac.

2 With no load connected to the unit's output, measure, in turn, the

voltage between terminals 4 and 6 then 5 and 7. Check that the
measurements are in the range 23.64V to 24.36V.

3 Connect to the output, a load that draws up to 2A from a supply

voltage between 105V and 264V ac, and draws 1.7A when the
supply voltage is less than 105V ac. Measure, in turn, the voltage
across terminals 4 and 6 and 5 and 7. Check that these
measurements are in the range 23.64V to 24.36V with a ripple
not greater than 100mV.

6.36 MTL5995 fieldbus power supply for

31.25kbit/s fieldbuses

The MTL5995 is a general purpose power supply unit designed for use
in 31.25kbit/s (H1) fieldbus systems. The MTL5995 complies with the
requirements of Fieldbus Foundation™ power supply Type 131 (non-IS
supply intended for feeding an IS barrier).).

To allow adequate heat dissipation under all likely thermal conditions, it
is recommended that MTL5995s are installed on DIN rail with a 10mm
space between adjacent units. MTL MS010 10mm DIN-rail module
spacers are available for this purpose (see section 4.2.1).

To comply with fieldbus standards, each bus must be terminated at both
ends. MTL's FBT1-IS or FCS-MBT fieldbus terminators (see section 6.37)
can be supplied for this purpose or, for installations in which the
MTL5995 is located at one end of the fieldbus trunk, it includes an
internal terminator which is enabled by a yellow switch (B) located on
the base of the unit (see figure 6.82). A second, red switch (A) in the
base of the unit should be kept in the normal mode position.

(For network and termination criteria

, see applicable fieldbus standards

and specification

IEC 61158-2, ISA-S50.02 for 31.25kbit/s fieldbus
systems, Foundation™ Fieldbus 31.25kbit/s Physical Layer Profile
Specification FF-816

and MTL's Application Brief AB001.)

4

5

6

L

E

N

7
8

+



Figure 6.81: Terminal assignments for MTL5991

A

B2

1

NORMAL MODE SW1

TERMINATOR OUT SW2

NOT USED

Red

Yellow

TERMINATOR IN

Label face

Base of unit

Figure 6.82: Functions of switches on the base of an MTL5995

and specifications are

IEC61158-2, ISA-S50.02 for 31.25kbit/s
fieldbus systems and FOUNDATION™ Fieldbus 31.25kbit/s Physical
Layer Profile Specification FF816.

Additional information on fieldbus termination can be found in

MTL's

AB001

and

AB002

application briefs.

6.37.1 Package details

The FBT1-IS terminator is designed for mounting on 35 x 7.5 mm or 35
x 15 mm DIN rail to EN50022.

6.37.2 Fitting FBT1-IS

Orientate the FBT1-IS as shown in Figure 6.82a and locate it on the
DIN rail. Using the DIN rail edge as the pivot point, press down the
other end until the package clicks into place on the other side of the rail.

6.37.3 Removal

Removal requires a screwdriver or similar flat blade. Locate the
screwdriver into the slot provided in the fixing bracket on the 'device'
side of the spur connector (see Figure 6.86). Carefully lever towards the
spur connector body until the mounting is released from the DIN rail and
lift it off the rail.

6.37.4 Connections

The +, - and cable screen (S) connections are indicated in Figure 6.87.
The terminals will accept cables with a cross sectional area of up to 4
mm2. A straight blade screwdriver with a maximum blade width of 3.5
mm is required to operate the terminals. The recommended tightening
torque is <0.9 Nm.

6.36.1 Wiring connections

See figure 6.83 for wiring connections and refer to MTL's Application
Brief AB001.

Note: To assist the process of terminating cable screens, terminals 7
and 10 are linked internally. Please note however that these terminals
are not earthed.

**Where supply voltage is 20 to 30V dc, ambient temperature limits are
–20°C to 60°C. If supply voltage is 20 to 35V dc, the ambient
temperature limits are –20°C to +55°C.

Table 6.17

**Where supply voltage is 20 to 30V dc, ambient temperature limits are

-20°C to 60°C. If supply voltage is 20 to 35V dc, the ambient
temperature limits are -20°C to +55°C.

6.36.2 Testing

Make the safe-area connections shown in figure 6.84 and, substituting
appropriate resistors for R

test

, carry out the checks shown in table 6.17

6.37 FBTI-IS fieldbus terminator

The FBT1-IS is a DIN rail mounting unit that provides the correct
termination for fieldbus circuits in either safe or hazardous areas.

The unit is certified for use in Zone 0, IIC, T4 locations, and fully
complies with the electrical characteristics requirements of section

22.7.5 of appropriate fieldbus standards. Applicable fieldbus standards

33

INM5000-6 Jul 2010

7
8
9

10
11
12

13
14

PSU

Switch

T

Fieldbus

T

T



+

20 to 30V dc

Vs
Vs+



+

FBT1*
Fieldbus
terminator

Fieldbus
device(s)

FBT1*
Fieldbus
terminator

Safe area

Figure 6.83: MTL5995 wiring diagrams and connections

R

test

Current (I1) Voltage across terminals

8 and 9 (V1)

1.8kΩ - 18.6V ≤ V

1

≤ 19.4V

56Ω 10W ~ 340mA -

0Ω < 500mA -

7
8
9

10
11
12

13
14

PSU

T



+

20 to 30V dc**

Vs
Vs+



+

R

test

R

test

I

1

6

5

4

3

2

1

Figure 6.84: Test circuit for MTL5995

S

S

+



+



F

E

GH

D

C

AB

63 mm

18 mm

64 mm

Figure 6.81: Terminator/Spur connector package

a) b )

Figure 6.86: a) fitting and b) removal

FBT1-IS

S

S

+



+



T

CAD

H
FE

Figure 6.87: Terminal assignments

Terminal Function

7 Internally linked to 10
8 & 11 Safe-area fieldbus device(s) connection –ve
9 & 12 Safe-area fieldbus device(s) connection +ve

10 Internally linked to 7
13 Supply –ve
14 Supply +ve

7 MAINTENANCE

Note: Limit tests and routine maintenance to those described in this

section and section 4. Return any isolator identified as faulty to the MTL
group company or representative from which it was purchased, for
repair or replacement.

7.1 Routine maintenance

Occasionally check the general condition of the installation to make sure
that no deterioration has occurred. At least once every two years (and
more frequently for particularly harsh environments), check that:

◆ isolators are of the types specified in the relevant documentation;

◆ isolators and connectors are correctly and legibly tagged,

connectors are plugged into the corresponding isolators and tag
details given comply with the relevant documentation;

◆ isolators are securely clipped to the DIN rail;

◆ all cable connections are properly made to the plugs;

◆ all plugs are fully inserted;

◆ all connecting cables are of the specified type and rating, are

correctly routed and segregated (particularly when fitted in
enclosures), and are not frayed or otherwise damaged;

◆ all cable screens are properly earthed;

◆ there is no sign of damage or corrosion.

7.2 Enclosures

The only maintenance needed for enclosures is cleaning and periodic
visual inspections. Clean external surfaces only, using soap and water;
do not use chemical solvents or proprietary cleaning fluids. Every year
(more frequently in harsh environments), inspect enclosures and check
that:

◆ they are attached securely to their mountings;

◆ any accumulation of water inside has been removed (using the

drain plug, if fitted);

◆ cable gland nuts are tight;

◆ there are no signs of any damage;

◆ all connections are properly made.

8 OTHER USEFUL DOCUMENTATION

MTL Hazardous Area Products Catalogue
AB001 Application Brief
AB002 Application Brief
INA5000 DofC and ATEX Safety Instructions
INM073A Connection and Configuration Manual

Customer drawings

CD5001-30 MTL5000 Power Bus Kits
CD5001-41 MTL5000 Series Tagging and Earth Rail

Accessories

CD5001-42 MTL5000 Tag and Earth Accessories
IEC 61158-2
ISA-S50.02 for 31.25kbit/s fieldbus systems
F

OUNDATION™ Fieldbus 31.25kbit/s Physical Layer Profile

Specification FF-816

HART® is a registered trademark of the HART Communication Foundation
Fieldbus Foundation™ is a trademark of Fieldbus Foundation, Austin, Texas, USA
F

OUNDATION

™ is a trademark of Fieldbus Foundation, Austin, Texas, USA

34

INM5000-6 Jul 2010

WARNING

If an isolator is faulty, DO NOT make repairs or
modifications as these may affect the intrinsic safety of
the unit.

35

INM5000-6 Jul 2010

9 APPENDIX A - INSTRUCTIONS FOR

MTL5500 SERIES

9.1 MTL5521 rotational speed monitor

A rotational speed monitor with over- and under-speed monitoring, has
proximity detector input, conforming to NAMUR/DIN 19234
standard. Easy configuration is by two push buttons on the top of the
unit and the unit has a frequency range of 0.001Hz to 10kHz (0.06
to 600000 min-

1

). A liquid crystal display on the top of the unit
displays the current frequency. The 0/4 to 20mA current output is
proportional to the rotational speed, and the unit has SPDT relay
output for over- and under-speed indication. Start-up delay is initiated
by the closure of a normally open contact. Three power supply
versions are available – 24V DC, 115V AC and 230V AC.

9.1.1 Wiring connections

Hazardous-area terminals
5 & 6 NAMUR sensor input connection.
7 & 8 Normally open switch contact for Start-up delay

function.
Safe-area terminals
9 & 13 0/4 to 20mA analogue output.
10, 11 & 12 Over- and under-speed relay output.
15 & 16 Power supply connection.

9.1.2 LED indications.

Pulse indication:

Yellow - indicates an input pulse

Red - input circuit fault
Pwr Supply voltage:

Green - device is operational
K

1

Limit value relay

Yellow - relay energized

9.1.3 Mounting instructions

The rotational speed monitor is suitable for either panel or DIN-rail
mounting. A minimum spacing of 3.5mm between the modules is
required when the modules are mounted horizontally. There is no
minimum spacing for vertically mounted units.

9.1.4 Configuration (figures 9.1 and 9.2)

Buttons S1 and S2 on the top of the unit are used to configure the
individual parameters of the unit. The required parameter Id, tb etc is
selected by pressing S2 until the parameter to be configured is displayed
and then, S1 must be pressed and held for approximately 3 seconds.
The left decimal will start flashing and the value can then be set, using
S1. S2 can then be used to adjust further decimals, the decimal point
and the exponent, in turn, returning eventually to the parameters menu.

Note: The unit does not have internal error detection. Incorrect
parameters can lead to malfunction or failure of the device.

Note: All MTL products are tested for electrical safety to EN 61010 to
comply with the EC Low Voltage Directive.

See also warning on page 1.

9.1.4.1 Menu parameters

The following parameters can be configured:
id User-specified identification number.
tb Time basis. The standard time base setting is

frequency (Hz). If other units are required, a
conversion factor has to be used. A conversion from
Hz to revolutions per minute requires a tb value of 60,
the measured rotational speed is then multiplied by
the factor tb.

nt Number of targets. The input frequency is divided by

the number of targets, nt.

F-0 Zero speed detection. If the input frequency falls

below the value F-0, the LCD display will show
'0000'. The value of F-0 must be less than the
switching threshold values, F-0<Uof.

Uof Switch-off threshold for under-speed monitoring. If the

input frequency falls below the value Uof, the limit
value relay will de-energise.

Uon Switch-on threshold for under-speed monitoring. If the

input frequency rises above the value Uon, the limit
value relay will energise (Uof < Uon).

Oon Switch-on threshold for over-speed monitoring. If the

speed falls below the value Oon , the limit value
relay will energise.

Oof Switch-off threshold for over-speed monitoring. If the

speed rises above the value Oof, the limit value relay
will de-energise (Oon < Oof).

9.1.4.2 Switching thresholds (figure 9.1)

Once the parameters tb and nt have been set, all the threshold values
will be in the user-defined units. The difference between the switch-on
and switch-off threshold values allows user-defined switching hysteresis
to be set. The limit value relay and current output performance are
illustrated in figure 9.1.

To deactivate under-speed monitoring set Uof and Uon to 0.To deactivate
over-speed monitoring set Oof and Oon to 9999*10

3

.

If both the over- and under-speed monitoring modes are deactivated the
relay operates as an alarm relay. If no errors occur during operation, the
relay is energized. If an error occurs in the input circuit, the relay de­energizes.

Iout Output current range: 0 to 20 mA or 4 to 20 mA.
F-IL The minimum frequency to be indicated by either 0 or

4 mA, depending upon Iout.

F-IH The maximum frequency for an output current of

20 mA. If F-IL > F-IH the output curve is reversed.

Tc Filter reaction time in seconds for smoothing the

Start

8888

8888

8888

8888

8888

tb Soft

S2

S1 (3 sec)

S1

S1

S1

S1

S2

S2

S2

S2

S2 S2

S2

8888

8888

8888

8888

S1

S1

S1

S1

S1

S2

S2

S2

S2

S2

. . .

S1

10

3

Figure 9.2: Configuration steps

24
22
20

4
0

Relay

status

OUT

m A

Relay de-energised

F-0 F-IL Uof Uon Oon Oof F-IH

f

Relay energised

Relay de-energised

Figure 9.1: Configuration values

36

INM5000-6 Jul 2010

current signal. The current output follows the rotational
speed change according to the preset time

-Br The value of the output current which indicates a

broken wire on the input circuit.

I-Sh The value of the output current indicating a short circuit on

the input circuit.

ICM Input circuit monitoring

off - disabled
Br - wire-break monitoring
Sh - short-circuit monitoring
Both - wire-break and short-circuit monitoring

Sud Start-up time delay in seconds. The start-up time delay

function is activated when the normally open contacts
across terminals 7 and 8 close, energizing the limit
value relay for a preset time. Consequently, an
under-speed indication is inhibited during system
start-up.

Soft Software version number.

9.2 MTL5531 voltage/current converter

Device provides hazardous-area current and voltage inputs (only one to
be used at any one time). It has short circuit protected voltage input and
active current output. Input, output and power supply are galvanically
isolated.

9.2.1 Wiring connections

Hazardous area terminals
1 & 2 Current input (passive).
3 & 4 Voltage input.
Safe area terminals
5 & 6 Output circuit.

MTL5531-xxx Li - active current output.
MTL5531-xxx LU - voltage output.

7 & 8 Power supply connection.

9.2.2 LED indications

Pwr Supply voltage:

(Green indicates that device is operational)

9.2.3 Mounting instructions

The MTL5531 is suitable for either panel or DIN-rail mounting.

9.2.4 Transfer characteristics

9.3 MTL5536 potentiometer converter

Provides repeat of a potentiometer input through an analogue signal in
the safe area. Accepts 3- or 5- wire potentiometer input, 800Ω to20kΩ
input range, with line resistance <50Ω. Two output versions are
available 0 to 20mA (MTL5536-11Li) or 0 to 10V (MTL5536-11LU). No
configuration is required, and input, output and power supply are
galvanically isolated.

9.3.1 Wiring connections

Hazardous area terminals
1 & 3 3- and 5- wire potentiometer power.
2 Potentiometer wiper
4 & 5 5-wire potentiometer sense.
Safe area terminals
7 & 8 Output:

MTL5536-11Li : 0 to 20mA output.
MTL5536-11LU : 0 to 10V output

11 & 12 Power supply connection.

9.3.2 LED indications

Pwr Supply voltage:

(Green indicates that device is operational)

9.3.3. 3- or 5-wire operation

3-wire configuration gives high enough accuracy for standard
operation. If a higher accuracy is required, or there is a problem with
high resistance lines due to long cable runs, then the 5-wire operation is
recommended.

9.3.4 Mounting instructions

The MTL5531 is suitable for either panel or DIN-rail mounting

Current input Voltage input

I (mA) RI(ΩΩ)I

max

(mA) V Ri (ΩΩ)V

max

Output circuit RL (ΩΩ)

MTL5531-11Li 0/4 to 20 100 < 40 0/2 to 10 50k < 39 0/4 to 20mA < 500
MTL5531-11LU 0/4 to 20 100 < 40 0/2 to 10 50k < 39 0/2 to 10V > 500
MTL5531-111Li 0 to 20 100 < 40 0 to 10 50k < 39 4 to 20mA < 500
MTL5531-112LU 4 to 20 100 < 40 2 to 10 50k < 39 0 to 10V > 500
MTL5531-113Li 0 to 10 175 < 40 0 to 5 70k < 39 4 to 20mA < 500
MTL5531-115Li 0/2 to 10 175 < 40 0/1 to 5 70k < 39 0/4 to 20mA < 500
MTL5531-115LU 0/2 to 10 175 < 40 0/1 to 5 70k < 39 0/2 to 10V > 500
MTL5531-119LU 2 to 10 175 < 40 1 to 5 70k < 39 0 to 10V > 500

MTL Instruments Pty Limited

9 /12 Billabong Street
Stafford
Queensland 4053
Australia
Tel: + 61 1300 308 374 Fax: + 61 1300 308 463
E-mail: [e-mail]

Cooper Electric (Shanghai) Co. Ltd.

Room 2001, China Life Tower
16 Chao Yang Men Wai Street
Chao Yang District, Beijing
China 100020
Tel: + 86 10 5980 0288 Fax: + 86 10 8562 5725
E-mail: [e-mail]

MTL Instruments sarl

Les Carrés du Parc
10 rue des Rosiéristes
69410 Champagne au Mont d’Or
France
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

MTL Instruments GmbH

An der Gümpgesbrücke 17
D-41564 Kaarst
Germany
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

MTL India

No. 36, Nehru Street
Off Old Mahabalipuram Road
Sholinganallur
Chennai - 600 119
India
Tel: + 91 (0)44 24501660/24501857 Fax: + 91 (0)44 24501463
E-mail: [e-mail]

MTL Italia srl

Via Cantù 11
I - 20092 Cinisello Balsamo MI
Italy
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

Cooper Crouse-Hinds Japan KK

MT Building 3F
2-7-5 Shiba Daimon
Minato-ku Tokyo
Japan 105-0012
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

Cooper Crouse-Hinds Korea

12F, Vision Tower
707-2 Yeoksam-dong, Gangnam-gu
Seoul 135-080
South Korea
Tel: [phone] Fax: [phone]

MTL Instruments BV

MTL Instruments BV
Terheijdenseweg 465
4825BK Breda
The Netherlands
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

Cooper Crouse-Hinds Pte Ltd.

No.2 Serangoon North Avenue 5
#06-01 Fu Yu Building
Singapore 554911
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

MTL Instruments

Villa No. 4, Sector 2-17, Street 6
PO Box 53234,
Abu Dhabi, UAE
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

Measurement Technology Limited

Great Marlings, Butterfield, Luton, Beds
England LU2 8DL
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

Cooper Crouse-Hinds MTL Inc

3413 N. Sam Houston Parkway W.
Suite 210
Houston TX 77086
USA
Tel: [phone] Fax: [phone]
E-mail: [e-mail]

Group Internet home page http://www.mtl-inst.com/

Members of The MTL Instruments Group