Rosemount Incus Operating Manual

Part Number: MAN-GDU-INCUS, rev. 7

GDU-Incus Ultrasonic Gas Leak Detector

Reference Manual

Release: July 2015

Important Instructions

Emerson Process Management designs, manufactures and tests products to function within specific
conditions. Because these products are sophisticated technical instruments, it is important that the
owner and operation personnel must strictly adhere both to the information printed on the product
nameplate and to all instructions provided in this manual prior to installation, operation, and
maintenance.

Installing, operating or maintaining an Emerson Process Management Product improperly could lead to
serious injury or death from explosion or exposure to dangerous substances. Comply with all
information on the product, in this manual, and in any local and national codes that apply to the
product. Do not allow untrained personnel to work with this product. Use Emerson Process
Management parts and work procedures specified in this manual.

In-depth specialist knowledge is an absolutely necessary condition for working with and on the GDU­Incus.

Authorized personnel for installing, operating, servicing and maintaining the GDU-Incus are instructed
and trained qualified personnel of the operating company and the manufacturer.

It is the responsibility of the operating company to;

• train staff,

• observe safety regulations

• follow the instruction manual

Operators must;

• have been trained

• have read and understood all relevant sections of the instruction manual before commencing work

• know the safety mechanisms and regulations

To avoid personal injury and loss of property, do not install, operate, maintain or service this instrument
before reading and understanding this instruction manual and receiving appropriate training

HEAVY INSTRUMENT! The GDU-Incus weighs 22 kg (49 lb) and therefore care must be taken when
lifting and carrying the unit. Ensure all bolts and fixings selected for mounting are suitable for the
weight and that the wall, pole, or mounting surface is solid and stable.

Notice

The contents of this publication are presented for informational purposes only, and while every effort
has been made to ensure their accuracy, they are not to be construed as warranties or guarantees,
expressed or implied, regarding the products or services described herein or their use or applicability.
All sales are governed by Emerson Process Management’s terms and conditions, which are available
upon request. We reserve the right to modify or improve the designs or specifications of such products
at any time.

Emerson Process Management does not assume responsibility for the selection, use or maintenance of
any product. Responsibility for proper selection, use and maintenance of any Emerson Process
Management product(s) remains solely with the purchaser and end-user.

To the best of Emerson Process Management’s knowledge the information herein is complete and
accurate. Emerson Process Management makes no warranties, expressed or implied, including implied
warranties of merchantability and fitness for a particular purpose with respect to this manual and, in no
event, shall Emerson Process Management be liable for any incidental, punitive, special or
consequential damages including, but not limited to, loss of production, loss of profits, loss of revenue
or use and costs incurred including without limitation for capital, fuel and power, and claims of third
parties.

Product names used herein are for manufacturer or supplier identification only and may be
trademarks/registered trademarks of these companies.

The Emerson logo is a trademark and service mark of the Emerson Electric Company.

Copyright © 2015 by Emerson Process Management, Slough, Berkshire, United Kingdom

All rights reserved. No part of this work may be reproduced or copied in any form or by any means ­graphic, electronic, or mechanical without first receiving written permission of Emerson Process
Management,

Slough, Berkshire, United Kingdom.

Warranty

1. Limited Warranty. Subject to the limitations contained in Section 10 (Limitation of Remedy

and Liability) herein, Seller warrants that (a) the licensed firmware embodied in the Goods will
execute the programming instructions provided by Seller; (b) that the Goods manufactured by
Seller will be free from defects in materials or workmanship under normal use and care; and (c)
Services will be performed by trained personnel using proper equipment and instrumentation
for the particular Service provided. The foregoing warranties will apply until the expiration of
the applicable warranty period. Sensors and detectors are warranted against defective parts
and workmanship as outlined in section 7.6. Products purchased by Seller from a third party for
resale to Buyer (Resale Products) shall carry only the warranty extended by the original
manufacturer. Buyer agrees that Seller has no liability for Resale Products beyond making a
reasonable commercial effort to arrange for procurement and shipping of the Resale Products.
If Buyer discovers any warranty defects and notifies Seller thereof in writing during the
applicable warranty period, Seller shall, at its option, (i) correct any errors that are found by
Seller in the firmware or Services; (ii) repair or replace FOB point of manufacture that portion of
the Goods found by Seller to be defective; or (iii) refund the purchase price of the defective
portion of the Goods/Services. All replacements or repairs necessitated by inadequate
maintenance; normal wear and usage; unsuitable power sources or environmental conditions;
accident; misuse; improper installation; modification; repair; use of unauthorized replacement
parts; storage or handling; or any other cause not the fault of Seller, are not covered by this
limited warranty and shall be replaced or repaired at Buyer’s sole expense and Seller shall not
be obligated to pay any costs or charges incurred by Buyer or any other party except as may be
agreed upon in writing in advance by Seller. All costs of dismantling, reinstallation, freight and
the time and expenses of Seller’s personnel and representatives for site travel and diagnosis
under this limited warranty clause shall be borne by Buyer unless accepted in writing by Seller.
Goods repaired and parts replaced by Seller during the warranty period shall be in warranty for
the remainder of the original warranty period or 90 days, whichever is longer. This limited
warranty is the only warranty made by Seller and can be amended only in a writing signed by an
authorized representative of Seller. The limited warranty herein ceases to be effective if Buyer
fails to operate and use the Goods sold hereunder in a safe and reasonable manner and in
accordance with any written instructions from the manufacturers. THE WARRANTIES AND
REMEDIES SET FORTH ABOVE ARE EXCLUSIVE. THERE ARE NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, AS TO MERCHANTABILITY, FITNESS FOR
PARTICULAR PURPOSE OR ANY OTHER MATTER WITH RESPECT TO ANY OF THE GOODS OR
SERVICES.

2. Limitation of Remedy and Liability. SELLER SHALL NOT BE LIABLE FOR DAMAGES CAUSED BY

DELAY IN PERFORMANCE. THE REMEDIES OF BUYER SET FORTH IN THE AGREEMENT ARE
EXCLUSIVE. IN NO EVENT, REGARDLESS OF THE FORM OF THE CLAIM OR CAUSE OF ACTION
(WHETHER BASED IN CONTRACT, INFRINGEMENT, NEGLIGENCE, STRICT LIABILITY, OTHER
TORT OR OTHERWISE), SHALL SELLER’S LIABILITY TO BUYER AND/OR BUYER’S CUSTOMERS
EXCEED THE PRICE TO BUYER OF THE SPECIFIC GOODS MANUFACTURED OR SERVICES
PROVIDED BY SELLER GIVING RISE TO THE CLAIM OR CAUSE OF ACTION. BUYER AGREES THAT
IN NO EVENT SHALL SELLER’S LIABILITY TO BUYER AND/OR BUYER’S CUSTOMERS EXTEND TO
INCLUDE INCIDENTAL, CONSEQUENTIAL OR PUNITIVE DAMAGES. THE TERM
“CONSEQUENTIAL DAMAGES” SHALL INCLUDE, BUT NOT BE LIMITED TO, LOSS OF
ANTICIPATED PROFITS, REVENUE OR USE AND COSTS INCURRED INCLUDING WITHOUT
LIMITATION FOR CAPITAL, FUEL AND POWER, AND CLAIMS OF BUYER’S CUSTOMERS.

Reference Manual Table of Contents

MAN-GDU-INCUS Revision 7 July 2015

Contents

Section 1 : Introduction ............................................................................ 1

1.1 Product overview ................................................................................................................ 1

1.2 Service support ................................................................................................................... 2

1.3 Return of material ............................................................................................................... 2

1.4 Product recycling/disposal .................................................................................................. 2

Section 2 : General operation .................................................................... 3

Section 3 : Installation .............................................................................. 4

3.1 Unpacking and inspection .................................................................................................. 4

3.2 Dimensions ........................................................................................................................ 4

3.3 Installation procedure ......................................................................................................... 5

3.3.1 Mechanical installation ...................................................................................... 5

3.4 Mounting ........................................................................................................................... 8

3.4.1 Wall / Flat surface mounting ............................................................................... 8

3.4.2 Pole mounting ................................................................................................. 10

3.4.3 Mounting with Exe Junction Box ....................................................................... 11

3.4.4 DNV mounting ................................................................................................. 12

3.5 Terminal Compartment Wiring (Non-Exe) ......................................................................... 14

3.5.1 General ............................................................................................................ 14

3.5.2 Wiring configurations ...................................................................................... 18

3.6 Exe Junction Box Wiring (Exe-Incus Only) .......................................................................... 19

3.7 External cables .................................................................................................................. 20

3.8 External ground ................................................................................................................ 20

3.9 Commissioning ................................................................................................................ 21

3.9.1 Visual inspection .............................................................................................. 21

3.9.2 Power-up ......................................................................................................... 22

Section 4 : Operation .............................................................................. 23

4.1 Normal operation ............................................................................................................. 23

4.1.1 Alarm level ....................................................................................................... 23

4.1.2 Delay time ....................................................................................................... 25

4.1.3 Automatic self-test .......................................................................................... 27

4.2 Sensor functionality check ................................................................................................ 27

4.3 Output options ................................................................................................................. 27

4.3.1 Relay Options ................................................................................................... 28

4.4 Display ............................................................................................................................. 28

4.5 4-20 mA output ................................................................................................................ 29

4.6 Fault outputs .................................................................................................................... 30

4.6.1 2.0 mA Sensor test fault ................................................................................... 30

4.6.2 1.0 mA Internal process fault ............................................................................ 30

4.6.3 0.5 mA ‘All Sensors dead’ fault ......................................................................... 30

4.6.4 0 mA Major fault .............................................................................................. 30

4.7 RS485 digital interface ...................................................................................................... 30

Section 5 : HART functionality ................................................................. 31

Section 6 : Maintenance ......................................................................... 32

6.1 Handheld test ................................................................................................................... 32

6.2 Verification test ................................................................................................................ 32

6.3 Troubleshooting ............................................................................................................... 32

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6.4 Storage ............................................................................................................................ 32

6.5 Spare parts and accessories .............................................................................................. 33

6.5.1 Spare parts ....................................................................................................... 33

6.5.2 Accessories ...................................................................................................... 34

Section 7 : Specifications ........................................................................ 35

7.1 General............................................................................................................................. 35

7.1.1 Detection method ........................................................................................... 35

7.1.2 Gases detected ................................................................................................ 35

7.1.3 Self-test ........................................................................................................... 35

7.1.4 Calibration ....................................................................................................... 35

7.2 Output signal .................................................................................................................... 35

7.2.1 4 — 20 mA ........................................................................................................ 35

7.2.2 Digital .............................................................................................................. 35

7.2.3 Relay 1 ............................................................................................................. 35

7.2.4 Relay 2 ............................................................................................................. 35

7.2.5 HART® .............................................................................................................. 35

7.3 Performance ..................................................................................................................... 36

7.3.1 Detection frequency range .............................................................................. 36

7.3.2 Dynamic range ................................................................................................. 36

7.3.3 Response time ................................................................................................. 36

7.3.4 Detection coverage.......................................................................................... 36

7.3.5 Start-up time ................................................................................................... 36

7.4 Electrical ........................................................................................................................... 36

7.4.1 Operating voltage range .................................................................................. 36

7.4.2 Power consumption ......................................................................................... 36

7.4.3 Cable entry ...................................................................................................... 36

7.5 Environmental .................................................................................................................. 37

7.5.1 Storage temperature ....................................................................................... 37

7.5.2 Operating temperature .................................................................................... 37

7.5.3 Relative humidity ............................................................................................. 37

7.5.4 Metallurgy ....................................................................................................... 37

7.5.5 Ingress protection ............................................................................................ 37

7.5.6 Weight ............................................................................................................. 37

7.5.7 Dimensions ...................................................................................................... 37

7.6 Warranty .......................................................................................................................... 37

Section 8 : Certifications ......................................................................... 38

8.1 Marking ............................................................................................................................ 38

8.2 ATEX................................................................................................................................. 41

8.3 IECEx ................................................................................................................................ 41

8.4 FM (US & Canada) ............................................................................................................. 41

8.5 EAC .................................................................................................................................. 41

8.6 INMETRO .......................................................................................................................... 41

8.7 KCs ................................................................................................................................... 41

Section 9 : Ordering information ............................................................. 42

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Section 1: Introduction

1.1 Product overview

The GDU-Incus is an ultrasonic gas leak detector used for detecting airborne ultrasound generated
from pressurized gas leaks.

Airborne ultrasound is generated when gas moves from a high-pressure area to a low pressure area
with a ratio in excess of 1.8:1 upstream to downstream, however, the GDU-Incus is only recommended
for pressures above 2 bar (30 psi) Gauge. The intensity of airborne ultrasound generated is dependent
on a number of factors including but not limited to gas pressure, leak size and gas temperature.

The GDU-Incus uses 4 individual Piezo ceramic sensing heads designed using a Patent pending floating
crystal design. The sensor design makes the sensing heads virtually indestructible and totally immune
to temperature, moisture, and other contaminants found in hazardous industry. The GDU-Incus uses a
continuous electronic monitoring test feature to ensure complete functionality.

The GDU-Incus has a large dynamic range which allows use in a wide range of applications from
offshore platforms to gas transportation systems. The multi-stage amplifier ensures a linear output
across the entire detector range without drop-off at each end of the range.

The GDU-Incus is not designed to detect specific gas types, LEL or ppm, but instead responds
instantaneously to the ultrasound produced by a wide range of leak sizes while being unaffected by
even the most extreme weather conditions. The GDU-Incus is rated to IP66/IP67, NEMA Type 4X to
withstand harsh environments.

The GDU-Incus is supplied with a 4-20 mA analog output, ‘multi-drop’ RS485 digital interface and a

®

interface.

HART

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1.2 Service support

Technical support for this product can be provided by contacting your local Emerson Process
Management sales office or by contacting the Technical Support department at

[e-mail]

1.3 Return of material

To expedite the repair and return of this product, proper communication between the customer and
the factory is important. Before returning a product for repair, e-mail [e-mail] for a
Return Material Authorization (RMA) number.

On the return of the equipment, include the following information:

1. RMA number provided to you by Emerson Process Management

2. Company name and contact information

3. Purchase order, from your company, authorizing repairs or request for quote

4. Ship all equipment, prepaid to:

Emerson Process Management
158 Edinburgh Avenue
Slough
Berkshire
SL1 4UE, UK

5. Mark all packages with Return for Repair and include RMA number

Pack items to protect them from damage and use anti-static bags or aluminum-backed cardboard as
protection from electrostatic damage.

All equipment must be shipped prepaid. Collect shipments will not be accepted.

1.4 Product recycling/disposal

Recycling of equipment and packaging should be taken into consideration and disposed of in
accordance with local and national legislations/regulations.

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Section 2: General operation

The GDU-Incus is omni-directional and is recommended to be mounted between 3 to 5 meters (10 to
16 feet) above the area of interest to eliminate ground absorption and reflections.

It is recommended that the area where the GDU-Incus is to be situated is ultrasonically mapped prior to
installation or at commissioning while all processes are running to establish a background noise level
for alarm purposes. The alarm level should be set above the background noise level. Please contact an
Emerson Process Management representative to request a mapping survey or mapping tools.

The GDU-Incus responds instantaneously to pressurized gas leaks or other sources of ultrasonic noise
between 25 kHz and 100 kHz. It is, therefore, recommended that a delay time is built in to the control
system or alternatively, programmed in the GDU-Incus when using it in standalone mode to prevent
spurious alarms. The delay time is recommended to be set at a minimum of fifteen (15) seconds but
this should be increased in response to the process located near to the detector as shown in the graph
in section 4.1.2.

The maximum area which can be monitored by a single GDU-Incus is affected by several factors such as
background (ambient) ultrasound level, gas pressure, leak size, temperature of the gas, and
environmental conditions. Emerson Process Management has formulated a series of calculations that
take all of these external factors into account and are able to determine accurate coverage information
for most installations. Please contact an Emerson Process Management representative to advise on
appropriate coverage for each installation.

The GDU-Incus detection coverage can be verified at installation or as part of a maintenance schedule
using the GDU-PTV Performance Target Verification Kit to simulate an actual gas release of known size
and pressure at the perimeter of the GDU-Incus detection radius. See section 6.5 for a listing of spare
parts and accessories or contact an Emerson Process Management representative for further details.

Compared to other Ultrasonic and traditional forms of detection, the GDU-Incus has the following
advantages:

 Gas does not need to reach the sensor for detection to occur
 Unaffected by weather conditions
 Sensors are unaffected by temperature, pressure, moisture, and contaminant build-up
 Multiple sensor redundancy in each unit
 Continuous self-test function
 No calibration required results in cost saving over detector lifecycle
 Can be remotely tested from up to 8 meter distance saving on maintenance scaffold costs
 4-20 mA Current Loop with HART communication as standard, plus relay outputs for ‘Fault’ and

‘Alarm’ conditions.

 Can operate standalone or as part of an interfaced control system.

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Section 3: Installation

The area in which the detector may be mounted must be in accordance with the certification of the
apparatus and in accordance with the standards of the appropriate authority in the country concerned.

Do not modify the enclosure or component parts as this will compromise the Hazardous Area
Certification.

Ensure all wiring and power supply to the detector is within specified operating parameters.

The GDU-Incus is a sealed unit with the exception of the terminal cover; the main enclosure is not to be
opened by anybody other than Emerson Process Management or Emerson Process Management
authorized personnel. All warranties and certification are nullified if these seals are broken or tampered
with.

The GDU-Incus is supplied without cable glands. Ensure all cable entry threads are sealed with an
appropriate plug to eliminate water ingress and thread damage. At installation, all shipping cable entry
plugs are to be removed and replaced with suitably approved Ex d cable glands or blanking plugs to
meet hazardous locations requirements. If the GDU-Incus is to be installed in a ‘Zone 1’ Hazardous Area
an Exd barrier seal must be used.

Identification tags must be firmly secured to the GDU-Incus bracket in the position shown on Figure 3-1
to prevent unwanted locally generated ultrasonic noise.

3.1 Unpacking and inspection

Carefully remove all of the components from the packaging and verify them against the enclosed
packing list. Inspect all components for obvious damage such as broken or loose parts. If you find any
components missing or damaged, notify your local Emerson Process Management representative or
the factory immediately.

3.2 Dimensions

Refer to Figure 3-1 for the dimensions of the GDU-Incus. Note: all dimensions are provided in
millimeters.

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Figure 3-1 Dimensions

3.3 Installation procedure

Mounting height of the GDU-Incus is recommended to be between 3 and 5 meters (10 to 16 feet)
above the floor level to eliminate ground reflections and absorption. The GDU-Incus may be used lower
than 3 meters (10 feet) but coverage may be reduced, please contact an Emerson Process
Management representative for more details.

Observe the area of installation for equipment capable of generating high levels of spurious airborne
noise that would not be classified as “normal background noise” such as pressure release valves, etc. If
any are present in the detector range of coverage, please contact Emerson Process Management or
monitor the detector when activated to ensure immunity.

3.3.1 Mechanical installation

The GDU-Incus incorporates a dedicated flameproof terminal compartment certified to Ex d, and a
flameproof main electronics compartment certified to Ex d both sealed to IP66/IP67. Care should be
taken when removing the terminal cover during installation to ensure that the flamepath surfaces are
not scratched or damaged.

The GDU-Incus has a large detection radius capability and care should be taken when positioning to
utilise the maximum coverage while eliminating blind spots and spurious alarms.

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The GDU-Incus has a variety of mounting options to incorporate installation into most situations found
in industrial environments such as wall / flat surface mounting (refer to section 3.4.1), vertical pole
mounting (refer to section 3.4.2), and mounting in an environment where DNV certification is required
(refer to section 3.4.4).

The GDU-Incus can be mounted in any orientation (unless a DNV bracket is used which fixes the
detector in vertical orientation) but care should be taken to position the display facing an area where
the information can be easily viewed.

Figure 3-2 3D view of detector coverage

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The GDU-Incus utilizes 4 independent sensor heads for full coverage. Figure 3-2 shows a 3D view of the
coverage (detector not to scale) at a 3m (10 foot) height above floor level with the detector pointing
vertically downwards. The GDU-Incus coverage is specified as meters radius at the floor level as this is
the minimum sensing distance. As shown, the entire area below the detector is covered as well as some
of the area above and around the detector. Each sensor overlaps the next, so areas underneath the
detector are covered by multiple sensors.

Figure 3-3 shows a 2D view of coverage when the detector is mounted vertically downwards and

highlights that the radius coverage stated is the minimum area covered.

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Figure 3-3 2D view of detector coverage

Figure 3-4 Coverage when mounted at an angle

Figure 3-4 shows coverage when the detector is mounted at an angle. This method is recommended

when the detector is mounted close to a wall or in an enclosed space to increase the coverage area.

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3.4 Mounting

3.4.1 Wall / Flat surface mounting

Figure 3-5 Wall/Flat surface mounting diagram

When mounting on a vertical flat surface such as a wall with no significant vibration it is sufficient to use
the standard mounting bracket supplied with the GDU-Incus. If vibration at fixing point is suspected,
please contact an Emerson Process Management representative for additional options.

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Figure 3-6 Wall mounting drilling template

Figure 3-4 shows the position of the mounting slots on the wall mounting bracket supplied with the

standard GDU-Incus. Pairs of Ø10 mm holes are to be drilled on the mounting surface between 30 mm
and 70 mm apart, with a vertical distance of 190 mm between the two pairs of holes.

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3.4.2 Pole mounting

Figure 3-7 Pole mounting diagram

In large open areas it is recommended that the GDU-Incus is pole mounted to take advantage of the
large omni-directional detection coverage. The detector should be mounted 3 to 5 meters (10 to 16
feet) high to eliminate reflections and ground absorption. The GDU-Incus may be used lower than 3
meters (10 feet) but coverage may be reduced, please contact an Emerson Process Management
representative for details.

The pole should be mounted to local standards and be capable of supporting the detector weight at the
installation height when environmental factors are taken into consideration.

The GDU-Incus is attached to the pole using 2 U-bolts fixed to the pole mounting adapter (wall bracket
can be used for pole mounting if the pole is 1.5” - 2” diameter). Suggested U-bolt torque is 45 Nm but
local standards should be used in the first instance.

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3.4.3 Mounting with Exe Junction Box

Figure 3-8 Exe-Incus mounting diagram

The Exe-Incus can either be wall or pole mounted as detailed above in sections 3.4.1 and 3.4.2
respectively, however the bracket holding the Exe junction box bracket must be located between the
‘wall mounting bracket’ and the ‘standard bracket’ during installation.

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3.4.4 DNV mounting

Where an installation requires equipment to be DNV certified, the GDU-Incus must be mounted using a
‘DNV Mounting Bracket’ (Part Number GDU-02-412) as shown in Figure 3-9.

Figure 3-9 DNV Mounting Diagram

Figure 3-9 shows the mounting arrangement for DNV Installation. All bolts should be torqued to 45

Nm, and spring washers are to be used in all cases.

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Figure 3-10 DNV mounting drilling template

Figure 3-4 shows the position of the mounting slots on the DNV mounting bracket supplied with the

DNV Incus. Pairs of Ø10 mm holes are to be drilled on the mounting surface between 70 mm and 90
mm apart, with a vertical distance of 75 mm between the two pairs of holes.

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3.5 Terminal Compartment Wiring (Non-Exe)

Failure to follow these installation guidelines could result in death or serious injury. Ensure that only
qualified personnel perform the installation.

Electrical shock could cause death or serious injury. Use extreme caution when making contact with
the leads and terminals.

Do not open the GDU-Incus enclosure when in a classified area or when an explosive atmosphere may
be present unless the power to the GDU-Incus has been removed.

The GDU-Incus terminal cover is certified to flameproof standards and should not be opened while
energized.

The detector housing should be connected to local ground via the external earth point as shown in

Figure 3-16. The ground wire should be minimum of 4 mm² (8 AWG) and as short as possible.

Termination at detector should be suitable for M6 (0.25”) fastener. Ensure earth wire is attached using
the supplied spring washer.

The standard GDU-Incus is temperature rated between -40°C and +85°C (-40°F and +185°F), and the
heated variant is temperature rated between -55°C and +85°C (-67°F and +185°F). Ensure that all cable
is rated to the appropriate temperature of installation.

3.5.1 General

Wiring codes and regulations may vary. Wiring must comply with all applicable regulations relating to
the installation of electrical equipment in a hazardous area and is the responsibility of the installer. If in
doubt, consult a qualified official before wiring the system.

In applications where the wiring is installed in conduit, the conduit must not be used for wiring to other
equipment.

For full EMC compliance ensure incoming cables are threaded through the ferrite beads (provided with
unit), see Figure 3-11.

To gain access to the terminal compartment, undo the six terminal cover fixing screws and raise the
terminal cover vertically until clear of the main enclosure. The terminal cover is held in place by means
of a stainless steel wire. The terminal cover can be lowered to the side of the detector during
installation but care should be taken to ensure the flamepath is not damaged. Refer to Figure 3-12 for
flamepath details. Tighten the six terminal cover fixing screws to a torque of 9 Nm.

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Figure 3-11 Ferrite bead locations

Cable entry is via suitable hazardous area approved and ingress protection certified cable glands
(customer supply) or conduit. The ATEX/IECEx approved GDU-Incus has 2 positions for M20 cable
glands, while the FM approved unit has 1 position for ¾” NPT conduit. Cable glands and conduit should
be fitted in accordance with manufacturers’ instructions for assembly to a certified flame proof
enclosure. All unused cable entries should be sealed using a flame proof certified plugging device.
Ensure all cable gland and plugging devices are ingress protected to the same standard as the
enclosure to maintain certification and are suitable for the size of cable used. If the GDU-Incus is to be
installed in an ATEX ‘Zone 1’ Hazardous Area an Exd barrier seal must be used. All FM approved units
(US and Canada) must be sealed within 18” of enclosure entry using a suitably rated conduit seal.

Thread size for cable entry is specified for each position on the terminal cover label. See section 8.1 for
further information.

The terminal compartment is sealed with two O-rings to prevent water ingress. Before closing it is
recommended that a visual inspection is undertaken to ensure the O-rings are in place and
undamaged. Also check the flame paths of the terminal cover and main enclosure for signs of damage.
Send the detector to Emerson Process Management for repair if the flame path is damaged. See

Figure 3-12 for O-ring and flame path positions.

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Figure 3-12 Flame path details

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Cable shield should be connected to instrument earth in the control room only unless extra RFI
protection is required and all local and site grounding regulations are met in which case the shield is to
be terminated to local ground via one of the internal earth points shown in Figure 3-13

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Figure 3-13 GDU-Incus terminal compartment diagram

Figure 3-13 shows a view of the GDU-Incus with the terminal cover removed. For single entry

enclosures customer cable entry is via position 1 whereas dual entry enclosures will use positions 1 and

2.

The terminals are separated into power and communications for terminal row 1 and relay outputs for
terminal row 2.

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3.5.2 Wiring configurations

Figure 3-14 Electrical connection drawing

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Refer to Figure 3-14 for descriptions of the cable entries for terminal rows 1 & 2.

For standard 3-wire connection cables should be connected to Terminal Row 1 in positions +24 V, 0 V
and current loop output connected to the mA terminal. Maximum loop resistance: 500 Ω.

Current source is the standard default operation; current sink is an option and should be specified at
time of order.

Relay data: 1.4 A, 30 Vdc switch voltage.

For a full description of fault relays refer to section 4.3.1 for more information.

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3.6 Exe Junction Box Wiring (Exe-Incus Only)

The terminal compartment on the Exe-Incus unit is sealed at the factory and should not be opened on
site. Instead, all wiring connections are made via the Exe junction box that is mounted adjacent to the
Incus unit.

Figure 3-15 Exe Incus Electrical connection drawing

Refer to Figure 3-15 for descriptions of the cable entries for the terminals inside the Exe Junction box.

The Exe-Incus is configured for a standard 3-wire connection; cables should be connected in positions
+24 V, 0 V and current loop output connected to the mA terminal.

Cable entry is via suitable hazardous area approved and ingress protection certified cable glands
(customer supply) or conduit. Ensure cable glands are ingress protected to the same standard as the
enclosure to maintain certification and are suitable for the size of cable used. Cable glands and conduit
should be fitted in accordance with manufacturers’ instructions.

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3.7 External cables

Customer cable should be chosen in accordance with Hazardous Area Certification and applicable local
regulations. Note: The GDU-Incus has a temperature rating of +85°C (185°F), when used in areas with
an ambient temperature above +60°C (140°F) ensure cable has a rating that is equal to or exceeds the
proposed maximum working temperature.

The following data indicates maximum cable length restriction due to voltage drop based on a nominal
input voltage of 24 VDC:

Conductor Cross Sectional Area/Gauge

Maximum Cable Length for Standard,
Non-Heated Incus

Maximum Cable Length for Heated
Incus

3.8 External ground

The detector housing should be connected to local ground via the external earth point as shown in

Figure 3-16. Wire should be a minimum of 4 mm² (8 AWG) and as short as possible. Termination at

detector should be suitable for M6 (0.25”) fastener. Ensure earth wire is attached using the supplied
spring washer.

Figure 3-16 External grounding point

0.5 mm²
20 AWG

540 m

1770 ft

75 m

240 ft

1.0 mm²
18 AWG

855 m

2800 ft

115 m 380

ft

1.5 mm²
16 AWG

1360 m

4470 ft

185 m 620

ft

2.5 mm²
14 AWG

2170 m

7120 ft

300 m 990

ft

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3.9 Commissioning

3.9.1 Visual inspection

Before powering the GDU-Incus, the following should be inspected. Refer to Figure 3-17 for key
locations on the GDU-Incus when completing this inspection.

 Ensure detector is correctly situated for area of detection.
 Ensure mounting bracket is secured to mounting points on the detector and mounting surface /

pole.

 Check pole mount (if present) for suitability to withstand detector weight and environment.
 Ensure external earth is correctly attached using spring washer.
 Ensure external cable is suitable for operating environment.
 Ensure correct cable gland installation and appropriate certification or local regulations have been

observed. Check correct cable installation in the terminal compartment; ensure terminal
compartment flame paths and seals are intact (Non-Exe units only).

 Ensure incoming cable is threaded through Ferrite beads (Figure 3-11) (Non-Exe units only).
 Tighten terminal cover bolts to the 9 Nm recommended torque (Non-Exe units only).
 Verify main enclosure bolts are in place. These have been torqued as required at the factory, and

should not be adjusted or tampered with.

 Check display glass for damage or contaminants that may obscure display.
 Check sensors and sensor pods for signs of damage.
 Ensure correct operating supply voltage.

Figure 3-17 Components of the GDU-Incus

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3.9.2 Power-up

Upon power-up a brief functionality check will run to ensure detector functionality, this lasts no more
than five (5) seconds. Once completed, the GDU-Incus will go into normal operation using the
factory/customer defaults specified at time of order or signal any faults that may be present. (Factory
default options can be found in section 4.1 and a list of faults can be found in section 4.6).

In addition the display will show the real-time ultrasonic sound level and the detector will become
responsive to RS485 commands for function setup and all relays will be energized or de-energized as
per defaults.

Note: If the GDU-Incus has been factory set for specific site requirements it is recommended to carry
out the steps outlined in section 4.2 before completion of commissioning.

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Section 4: Operation

4.1 Normal operation

On power-up the GDU-Incus initializes a diagnostic check and then enters normal operation mode as
per factory defaults supplied.

Factory Op mode 71 settings;

 4-20 mA = 40-120 dB (Linear scale factor)
 Display brightness set to 12. Viewing distance over 10 m (33 ft) in an outdoor environment
 Real time instantaneous ultrasonic sound level shown on display in dB
 Relays are energized open, loss of power causes alarm (fail-safe)
 Relays are set to non-latching
 Reset alarms enabled; allows latched relays to be reset and restarts alarm delay
 Alarm level set at 70 dB for relay output
 Delay time set to 15 seconds for relay output
 RS485 ID set to 1
 All communication ports are active and ready to receive commands

4.1.1 Alarm level

The ‘Alarm Level’ is the ultrasonic sound level at which an alarm state is triggered. During the alarm
state the display flashes, the relays switch states and the current loop becomes active if one or more
sensors were in fault mode (if no sensors are in fault the current loop will already be outputting dB
level).

To avoid false alarms it is recommended to set the alarm level above the background level established
by mapping when all processes are operational. If the background level is unknown it is recommended
to analyze the background using the detector itself. Care should be taken to observe all processes that
may cause intermittent ultrasonic noise such as pressure relief valves.

Please contact an Emerson Process Management representative for advice on alarm levels.

Note: the higher the alarm level the smaller the detector coverage radius, it is therefore important to
establish a safe alarm level at the lowest permissible value.

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Figure 4-1 Suggested alarm levels

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Figure 4-1 shows the suggested alarm level settings for known background sound levels. The values

shown have been found to provide sufficient immunity against most spurious alarms, however care
should be taken to survey the area of installation for potential spurious noise.

If background levels are unknown, typical historical process background levels can be used along with a
safety factor. Please contact an Emerson Process Management representative for historical values and
guidance.

Alarm levels can be set in the detector or at the control panel. Most installations set the alarm levels in
the control system.

Factory Default standard alarm level is 70 dB.

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4.1.2 Delay time

To avoid spurious alarms it is recommended that a delay time be used for non-toxic gas applications or
when instantaneous detection is not required. The delay timer is activated from the point at which the
alarm threshold is first exceeded. If the ultrasonic noise drops below the alarm level threshold the delay
time will be reset as shown in Figure 4-3. If the ultrasonic noise level remains above the alarm level
threshold for the duration of the delay time the alarm will be activated as shown in Figure 4-2.

Alarm delay time should be assessed with regards to the following:

 Detector proximity to release valves and intermittent ultrasonic noise sources
 Process leak severity, toxic / non-toxic, acceptable leak size before alarm
 Existing site protocols and local regulations

Note: If a gas leak occurs during spurious noise the delay time will continue from the first instance of
noise above the alarm threshold level.

Factory Default standard delay time is 15 seconds.

Figure 4-2 Graph showing alarm activation with leak

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Figure 4-3 Graph showing no alarm activation with spurious noise

In Figure 4-3 noise 1 and 2 are spurious noise spikes of approx. 1.5 seconds, typical of man-made
ultrasonic noise produced through normal maintenance procedures. Noise 3 is a longer spurious noise
of approx. 13 seconds typical of a pressure relief valve. Delay time is introduced to ignore spurious
noise spikes as the detector will reset when noise level drops below the alarm level before the delay
time is reached.

Figure 4-4 Graph showing alarm activation with spurious noise and leak

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Figure 4-4 shows detector response when a leak is encountered during a spurious noise spike such as a

pressure relief valve. Noise 1 represents a pressure relief valve actuating for approximately 13 seconds
before a leak (noise 2) occurs. The detector starts the delay time when the pressure relief valve opens
and continues to monitor for leaks. If a leak occurs during a spurious noise spike the delay time will be
reduced by the duration of the spurious noise spike.

It is important that all spurious noise spikes of significant duration within the detector coverage are
identified. It is recommended that the alarm delay is set to a value greater than the maximum spurious
noise spike operating duration. If two or more spurious noise sources are situated within the detector
coverage area, it is recommended to assess whether activation of these sources can overlap in time, in
which case the delay time should be extended accordingly.

4.1.3 Automatic self-test

The automatic self-test checks the complete detector every 320 ms by sending an electrical signal of
known amplitude through the sensing circuitry and analyzing the result, without interrupting the
normal functionality of the sensor. If drift, component failure or damage occurs a fault is signaled, refer
to section 4.6.

4.2 Sensor functionality check

The sensors on the GDU-Incus are factory calibrated and do not require adjustment. Before operation
functionality checks are recommended to ensure correct installation. On power-up, the GDU-Incus will
perform a diagnostic check to ensure all main functions are operational, and continuously monitors the
sensors via the built in self-test.

Sensor functionality can be checked in two ways;

 GDU-Incus handheld series test transmitter sound source. Ensure that the background ultrasonic

level is suitable for the distance of proposed test transmitter test. Aim the transmitter at the sensor
face from a known distance, The GDU-Incus display dB level will rise according to the hand held
device used and distance. Check all four (4) sensors, if possible, by moving around the detector and
repeating.

 Test verification kit — a pressurised gas release of a known pressure and size at a known distance.

The GDU-Incus display level will rise according to the size, pressure, and distance used.

4.3 Output options

The GDU-Incus comes with most industry standard forms of communication as standard. This enables
the detector to be operated as part of a system, a standalone unit, or hard wire linked to form a sub
network.

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4.3.1 Relay Options

The GDU-Incus has two relays configured as follows for the standard factory default;

Relay Type Factory Default Setting

1 Fault Energized in normal operating condition, de-energized in fault condition, non-

latching.

2 Alarm Energized in normal operating condition, de-energized in alarm condition, non-

latching.

Relay Data

Maximum switching current 1.4 A

Maximum switching voltage 30 VDC

Relay configuration can be changed to suit installation requirements using the user changeable
functions, options include Normally Open / Normally Closed condition and latching / non-latching.

Refer to GDU-INCUS RS485 Specification document (MAN-GDU-INCUS-RS485) for more information on
setup of the relays.

4.4 Display

The GDU-Incus incorporates a 5 digit x 7 segment, 8 mm high x 4 mm wide character LED display with
red numerals as standard.

During operation the real-time dB level is continuously shown while below the programmed alarm level
and flashing when above the programmed alarm level.

Figure 4-5 Example of real-time dB level display ‘53dB’

If a maintenance/minor fault occurs the display will continue to display the real-time dB value, but will
also show a flashing red dot on digit 1 to indicate that a fault has occurred.

If a major fault occurs, the display will shut down.

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Display delay (pulse filter) can be set to delay the results shown on the LED to eliminate spiked spurious
noise events and display a more consistent value.

Display settings can be changed using the user changeable functions; Refer to GDU-INCUS RS485
Specification document (MAN-GDU-INCUS-RS485).

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4.5 4-20 mA output

Figure 4-6 4-20 mA output values (example shows default Op-Mode 71)

Figure 4-6 shows the 4-20 mA output values for GDU-Incus during normal operation and under various

fault conditions. The value on the left side shows the mA output tolerance band, internal fault is set for
a 1.0 mA output with a tolerance of 0.8 to 1.2 mA for example.

Normal operation is shown with an upper tolerance of 4.7 mA (+/-0.3 mA) as the gain is usually set to a
minimum working level of 47 dB.

mA outputs are grouped in descending order to signify importance and to allow for instant status
recognition, see section 4.6;

Normal operation between 4 to 20 mA (+/- 0.2 mA) — detector working, no fault conditions.

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4.6 Fault outputs

4.6.1 2.0 mA Sensor test fault

One or more sensor heads fail to respond with a correct value during the automatic self-test. Output is
continuous at 2.0 mA unless the test is subsequently passed successfully or an alarm condition occurs,
in which case the normal sound level is transmitted on the current loop.

4.6.2 1.0 mA Internal process fault

Continuous 1.0 mA (+/-0.2 mA) output for any known internal or external faults which include over­voltage, high/low external voltage, blown fuse, or high/low internal voltage.

4.6.3 0.5 mA ‘All Sensors dead’ fault

Continuous 0.5 mA (+/-0.2 mA) output indicating that all 4 sensors have failed self-test. Firmware
version 3.4 onwards. The GDU-Incus should be returned to Emerson Process Management for repair.

4.6.4 0 mA Major fault

0 mA output is either caused by a total loss of power to the detector, or a serious microprocessor fault.
If a fault occurs due to loss of power, the fault will be cleared when power is reapplied to the detector. If
a serious microprocessor fault occurs, the GDU-Incus should be returned to Emerson Process
Management for repair.

4.7 RS485 digital interface

The GDU-Incus incorporates an RS485 digital interface which allows access to sensor status and setting
information. The RS485 interface allows the device to communicate in a simple point to point
configuration or as part of a larger, multi-drop network. (The majority of the supported commands are
duplicated on the alternative Infra-Red ‘remote-access’ interface).

The RS485 interface uses a Baud rate of 2400 and ideally should be wired via shielded ‘twisted pair’
cable to reduce interference, especially for cable runs longer than a few meters.

Full technical details of the packet structure and list of supported commands used in the RS485
communications interface are provided in the GDU-INCUS RS485 Specification document (MAN-GDU­INCUS-RS485) which is available on request.

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Section 5: HART functionality

The GDU-Incus has HART communication enabled by default. The HART communication mode is
standard current output FSK, to HART protocol revision number 7. The Device reports the Primary
Variable (PV) measurement of Sound Pressure Level in units of dB. The Secondary Variable (SV) reports
the internal case temperature (degrees Celsius) of the GDU-Incus. The Tertiary variable (TV) reports the
temperature of the heated section of the Incus, if the Heater option is fitted, otherwise will report the
same data as the Secondary Variable.

A Device description (DD) file for Emerson AMS and 375/475 field terminals is available from Emerson
Process Management. In addition, the unit can be used with FDT frame applications using a generic
DTM.

Full technical details of the HART Interface are provided in the GDU-INCUS HART Field Device
Specification document (MAN-GDU-INCUS-HART) which is available on request.

Notes:

1) The GDU-Incus does not support the Delayed-Response Mechanism, Burst-Mode or Write

Protection.

2) The HART device parameters ‘Tag’ and ‘Long Tag’ are set to ‘INCUS’ and ‘GDU-02-INCUS’ by

default. They should be set-up on site, to allow unique identification, if required.

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Section 6: Maintenance

6.1 Handheld test

The GDU-01-TT test transmitter can be used to emit an ultrasonic tone of 40 kHz with a sound pressure
level of approximately 106 dB at 1 m (3 ft). Using the GDU-01-TT handheld device makes testing the
GDU-Incus and other types of ultrasonic detectors quick and cost effective as it may be undertaken at
floor level at distances of up to 8 m (26 ft) (dependent on background noise) provided line of sight with
the sensor can be achieved. It is recommended that all alarms are disabled and the 4-20 mA output is
monitored from the control room or observed on the display. Testing is carried out to ensure that the
sensors are functioning correctly in addition to any internal test function contained within the GDU­Incus. It is recommended that a handheld test is undertaken in line with existing site maintenance
procedures.

Note: ensure that any internal test functions are disabled or not activated when undertaking a
handheld test to avoid spurious results.

6.2 Verification test

The GDU-PTV-01 performance target verification kit can be used to simulate an actual gas release to
test both functionality and performance of ultrasonic gas detectors by generating a ‘burst release’
representative of that expected in the event of a gas leak. The GDU-PTV-01 should be used at the
perimeter of the detector coverage to ensure that all leaks will be detected. It is recommended that all
alarms are disabled and the 4-20 mA output is monitored from the control room or observed on the
display. Testing is carried out to ensure that the sensors are functioning correctly in addition to any
internal test function contained within the GDU-Incus with respect to sensor response and coverage. It
is recommended that a verification test is undertaken at installation and in line with existing site
maintenance procedures.

6.3 Troubleshooting

The GDU-Incus cannot be repaired in the field. If a problem should develop, carefully check for faulty
wiring. If it is determined that the problem is caused by an electronic defect, the device must be
returned to the factory for repair (refer to 1.2 and 1.3 for instructions).

6.4 Storage

The detector should be stored in locations free from dust and moisture. The storage temperature
should be well within the limits of the certified temperatures of the equipment. See Section 7 for
storage temperatures.

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6.5 Spare parts and accessories

6.5.1 Spare parts

Enclosure Fastener Kits. Terminal cover fastener kit. Consists of 6 terminal cover fasteners

and retaining washers.

Terminal Cover O Ring Upper Replacement terminal cover O ring for upper position, standard.

Terminal Cover O Ring Lower Replacement terminal cover O ring for lower position, standard.

Please refer to individual spare part installation sheets for further information.

Description Part number

Terminal Fastener Kit. Replacement Terminal Cover fasteners and retaining
washers

Terminal Cover O Ring Upper GDU-02-TCU

Terminal Cover O Ring Lower GDU-02-TCL

GDU-02-TCFK

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6.5.2 Accessories

U-Bolt Kit Consists of two U-bolts and all fasteners required to allow the

GDU-Incus to be pole mounted using the standard mounting
bracket. Size of U-bolt should be specified at time of order.

Test Transmitter Consists of a handheld, rechargeable ultrasonic sound emitter

with carrying case, charger, and shoulder strap to allow remote
independent testing of any ultrasonic gas leak detector from
floor level. Note: the test transmitter is not hazardous area
approved and will require a hot work permit.

PTV Kit Consists of 2 x 10 litre Nitrogen Gas cylinders (150 BAR) and a

high pressure gas regulator which are attached to a trolley for
portability.

Please refer to individual accessory datasheets for further information or contact an Emerson Process
Management representative.

Description Part Number

Test Transmitter. Handheld rechargeable Ultrasonic Sound Emitter GDU-01-TT

Performance Target Verification (PTV) Kit GDU-PTV-01

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Section 7: Specifications

7.1 General

7.1.1 Detection method

Floating Piezo Ceramic — non consumable, non-ageing

7.1.2 Gases detected

All pressurized gases, minimum leak pressure 2 bar (Gauge), leak size dependent

7.1.3 Self-test

Continuous electronic check of sensor integrity

7.1.4 Calibration

Factory set

7.2 Output signal

7.2.1 4 — 20 mA

Current source 4 — 20 mA, corresponds to 40 to 120 dB SPL — Maximum load resistance 500 Ω
standard.

Current sink 4-20 mA (option)

7.2.2 Digital

RS485 interface

7.2.3 Relay 1

Error / Fault (NO or NC option)

Load: 1.4 A max. Switch Voltage 30 Vdc max. Contact resistance 70 mΩ

7.2.4 Relay 2

Alarm (NO or NC option)

7.2.5 HART

Supplied as standard.

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7.3 Performance

7.3.1 Detection frequency range

25 kHz to 100 kHz

7.3.2 Dynamic range

40 dB to 120 dB SPL (In standard operating mode)

7.3.3 Response time

Instantaneous (Less than 1 second with HART® outputs; alarm delay via 1 second variable increments —
customer programmable)

7.3.4 Detection coverage

2 to 20 meters (7 to 65 foot) radius (leak pressure, size and background level dependent). Greater
distances may be achieved subject to application consultation.

7.3.5 Start-up time

Less than 5 seconds

7.4 Electrical

7.4.1 Operating voltage range

15 to 30 Vdc

7.4.2 Power consumption

Standard Unit: 250 mA (at maximum display brightness) during normal operation

Heated Unit: 1.5 A at maximum display brightness and with heaters drawing maximum current (at ­55°C)

7.4.3 Cable entry

ATEX/IECEx/INMETRO/EAC/KOSHA: Dual M20 cable entries.

FM (US & Canada): Single ¾” NPT conduit entry

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7.5 Environmental

7.5.1 Storage temperature

-55°C to +85°C (-67°F to +185°F)

7.5.2 Operating temperature

Standard Unit: -40°C to +85°C (-40°F to +185°F)

Heated Unit: -55°C to +85°C (-67°F to +185°F)

7.5.3 Relative humidity

Humidity (operating): 0 to 100% relative humidity

7.5.4 Metallurgy

Stainless steel (AISI 316)

7.5.5 Ingress protection

IP66/IP67
Type 4X

7.5.6 Weight

Approx. 18 kg (39.8 lb.)

7.5.7 Dimensions

(without bracket) Ø210 x 272 mm (Ø8 ¼“ x 10 ¾“)

7.6 Warranty

18 months after shipment or 12 months after installation, whichever comes first

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Section 8: Certifications

8.1 Marking

Figure 8-1 Nameplate locations

The GDU-Incus has several areas that contain important information for installation and use which are
detailed below. Figure 8-1 shows the position of the nameplate, certification plate, and the terminal
cover plate. The plates supply information to comply with ATEX Directive 94/9/EC, ensure that all three
are fitted and clearly legible before installation.

Figure 8-2 Manufacturing nameplate

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Figure 8-3 ATEX/IECEx Certification nameplate (Standard Incus)

Figure 8-4 ATEX/IECEx Certification nameplate (Heated Incus Variant)

Figure 8-5 FM Certification nameplate

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Figure 8-6 ATEX/IECEx terminal cover label

Figure 8-7 FM terminal cover label

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Figure 8-6 and Figure 8-7 show the ATEX/IECEx and FM Terminal cover labels respectively. The thread
sizes of the enclosure entries situated below the label are shown on the label. If the thread size box is
empty the thread position is not machined.

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8.2 ATEX

II 2 G Ex d ib IIB+H2 T4 Gb IP66/IP67

-55°C/-40°C ≤ Ta ≤ +85°C
ITS09ATEX16836X

8.3 IECEx

II 2 G Ex d ib IIB+H2 Gb T4 IP66/IP67

-55°C/-40°C ≤ Ta ≤ +85°C
ITS 10.0004X

8.4 FM (US & Canada)

Class I, Div.1 Groups B, C, and D T4
Class I, Zone 1 AEx/Ex d ib IIB+H

-40°C ≤ Ta ≤ +85°C, Type 4X
3043275

T4

2

8.5 EAC

1Ex d ib IIB+H2 T4 Gb X

-55°C/-40°C ≤ Ta ≤ +85°C
RU C-GB.ГБ04.B.00297

8.6 INMETRO

Ex d ib IIB+H2 T4 Gb

-55°C/-40°C ≤ Ta ≤ +85°C
UL-BR 15.0063X

8.7 KCs

Ex d ib IIB+H2 T4

-55°C/-40°C ≤ Ta ≤ +85°C
14-KB4BO-0294X

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Section 9: Ordering information

Model Option Description

GDU-INCUS Ultrasonic Gas Leak Detector

Level 1 Conduit / Cable Entry

-134 1 x 3/4"NPT (cFMus approved only)

-220 2 x M20 (STANDARD, Not Available for cFMus Certified Units)

Level 2 Op. Mode

01 Stepped analogue signal (bi-state: 4 mA no alarm; 12 mA alarm)

02 Stepped analogue signal (bi-state: 4 mA no alarm; 20 mA alarm)

-50 4-20 mA = 58-104 dB

-65 4-20 mA = 40-200 dB

-71 4-20 mA = 40-120 dB (Standard)

-97 4-20 mA = 40-104 dB

Level 3 Certification

-A ATEX, IECEx, CE. Tamb = -40 °C to +85 °C (-40 °F to +185 °F)

-B ATEX, IECEx, CE. Tamb = -55 °C to +85 °C (-67 °F to +185 °F)

-E EAC. Tamb = -55 °C to +85 °C (-67 °F to +185 °F). Russia / Kazakhstan / Belarus

-F FM. Tamb = -40 °C to +85 °C (-40 °F to +185 °F) USA/Canada

-K KCs. Tamb = -40 °C to +85 °C (-40 °F to +185 °F) Korea

-M INMETRO. Tamb = -40 °C to +85 °C (-40 °F to +185 °F) Brazil

Level 4 Output

-H Current Source, HART (Standard)

-J Current Sink, HART

Level 5 Mounting

-A Standard bracket

-D DNV bracket

-N NORSOK Compliant (Indirect Exe termination)

Level 6 Features

-01

-02

-04

-05

-06

Finish = Electropolished 316 SS

Finish = Electropolished 316 SS with TAG

Finish = Electropolished 316 SS 1 x SS Exd plug fitted

Finish=Electropolished 316SS 1 x SS Exd plug +TAG fitted

Finish=Electropolished 316SS 1 x Brass Exd plug +TAG fitted

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GDU‐INCUS‐220‐71‐A‐H‐A‐01

MAN-GDU-INCUS

Revision 7

July 2015

Emerson Process Management
Rosemount Measurement Ltd.
158 Edinburgh Avenue, Slough, Berkshire,
SL1 4UE, UK
Tel [phone]
Fax [phone]

Rosemount Measurement Limited, registered in England and Wales No. 293743, VAT#864383106
Registered Office: 2nd Floor Accurist House, 44 Baker Street, London W1U 7AL

©2015 Emerson Process Management. All rights reserved.

Emerson Process Management, Rosemount Analytical, Net Safety Monitoring, and Groveley Detection Limited are marks of Emerson Process Management
group of companies. All other marks are the property of their respective owners.

The contents of this publication are presented for information purposes only, and while effort has been made to ensure their accuracy, they are not to be
construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. All sales are
governed by our terms and conditions, which are available on request. We reserve the right to modify or improve the designs or specifications of our products
at any time without notice.

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