Rosemount Legacy Manual: 975UR UV/IR Flame Detector Manuals & Guides

Rosemount™ 975UR

Legacy

Ultraviolet Infrared Flame Detector

Reference Manual

00809-0100-4978, Rev DD

November 2021

Legal notice

Legacy

The device described in this document is the property of Emerson.
No part of the hardware, software, or documentation may be reproduced, transmitted, transcribed, stored in a retrieval system,

or translated into any language or computer language, in any form or by any means, without prior written permission from
Emerson.

While great efforts have been made to ensure the accuracy and clarity of this document, Emerson assumes no liability resulting
from any omissions in this document or from misuse of the information obtained herein. The information in this document has
been carefully checked and is believed to be entirely reliable with all of the necessary information included. Emerson reserves the
right to make changes to any products described herein to improve reliability, function, or design and reserves the right to revise
this document and make changes from time to time in content hereof with no obligation to notify any persons of revisions or
changes. Emerson does not assume any liability arising out of the application or any use of any product or circuit described herein;
neither does it convey license under its patent rights or the rights of others.

WARNING

All individuals who have or will have responsibility for using, maintaining, or servicing this product must read this document
carefully.

WARNING

Physical access

Unauthorized personnel may potentially cause significant damage to and/or misconfiguration of end users’ equipment. This could
be intentional or unintentional and needs to be protected against.

Physical security is an important part of any security program and fundamental to protecting your system. Restrict physical access
by unauthorized personnel to protect end users’ assets. This is true for all systems used within the facility.

CAUTION

Equipment damage

This device is not field repairable due to the meticulous alignment and calibration of the sensors and the respective circuits.
Modifying or repairing the internal circuits may impair the system's performance and void the Emerson product warranty.

Do not attempt to modify or repair the internal circuits or change their settings.

Warranty

1. Limited Warranty . Subject to the limitations contained in Section 2 (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.

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

2

with any written instructions from the manufacturers. THE WARRANTIES AND REMEDIES SET FORTH ABOVE ARE

Legacy

EXCLUSIVE. THERE ARE NO REPRESENTATIONS OR WARRANTIES OF ANY KIND, EXPRESSED 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.

Technical support

To get technical support for this product, contact your local Rosemount representative or the Rosemount Technical Support
department at [phone] or [e-mail]

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, call [phone] or email [e-mail] for a return material authorization

(RMA) number.
On the return of equipment, provide the following information:

1. RMA number provided to you by Emerson

2. Company name and contact information

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

Ship all equipment prepaid to:
Emerson Automation Solutions
Measurement Solutions
6021 Innovation Blvd
Shakopee, MN 55379
Mark all packages with "Return for Repair" and include the RMA number.
Pack items to protect them from damage and use anti-static bags or aluminum-backed cardboard as protection from electrostatic

damage.
Ship all equipment prepaid. Emerson will not accept collect shipments.

Abbreviations and acronyms

Abbreviation or acronym Definition

ATEX Atmospheric explosives

AWG American wire gauge

BIT Built-in test

EMC Electromagnetic compatibility

EOL End of line

FOV Field of view

®

HART

IAD Immune at any distance

IECEx International Electrotechnical Commission Explosion

IPA Isopropyl alcohol

Highway addressable remote transducer - communication protocol

3

Abbreviation or acronym Definition

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IR Infrared

JP5 Type of jet fuel

Latching Refers to relays remaining in the ON state even after the ON condition has been

LED Light emitting diode

LPG Liquified petroleum gas

mA Milliamps (0.001 amps)

®

Modbus

N.C. Normally closed

N.O. Normally open

N/A Not applicable

NFPA National Fire Protection Association

NPT National pipe thread

RS485 Communication protocol allowing bi-directional communication

PN Part number

SIL Safety integrity level

UNC Unified coarse thread

Vac Volts alternating current

Vdc Volts direct current

removed.

Master-slave messaging structure

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Reference Manual Contents

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00809-0100-4978 November 2021

Contents

Chapter 1 Introduction.............................................................................................................. 7

1.1 Overview..................................................................................................................................... 7

1.2 Ordering information...................................................................................................................8

1.3 Features and benefits.................................................................................................................11

1.4 Principles of operation............................................................................................................... 11

1.5 Performance considerations...................................................................................................... 15

1.6 Internal detector tests............................................................................................................... 22

Chapter 2 Installing the detector..............................................................................................27

2.1 General guidelines.....................................................................................................................27

2.2 Unpack...................................................................................................................................... 28

2.3 Checking the product type........................................................................................................ 28

2.4 Required tools........................................................................................................................... 28

2.5 Certification instructions........................................................................................................... 29

2.6 Installing cables......................................................................................................................... 30

2.7 Installing the tilt mount (PN 00975-9000-0001)........................................................................ 30

2.8 Connect the detector.................................................................................................................34

2.9 Configure the detector.............................................................................................................. 37

Chapter 3 Operating the detector............................................................................................ 41

3.1 Power up................................................................................................................................... 41

3.2 Safety precautions.....................................................................................................................41

3.3 Testing procedures....................................................................................................................42

Chapter 4 Maintenance and troubleshooting........................................................................... 45

4.1 Maintenance..............................................................................................................................45

4.2 Troubleshooting........................................................................................................................46

Appendix A Specifications and reference data.............................................................................49

A.1 Technical specifications.............................................................................................................49

A.2 Electrical specifications..............................................................................................................49

A.3 Outputs.....................................................................................................................................50

A.4 Mechanical specifications..........................................................................................................52

A.5 Environmental specifications.....................................................................................................52

Appendix B Wiring instructions.................................................................................................. 55

B.1 General instructions for electrical wiring....................................................................................55

B.2 Typical wiring configurations.....................................................................................................57

Appendix C RS-485 communication network.............................................................................. 63

Appendix D Accessories.............................................................................................................. 65

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D.1 Flame simulator........................................................................................................................ 65

D.2 Tilt mount: PN 00975-9000-0001..............................................................................................71

D.3 Duct mount...............................................................................................................................71

D.4 Weather cover: PN 00975-9000-0003.......................................................................................72

D.5 Air shield: PN 00975-9000-0005................................................................................................73

Appendix E SIL-2 features........................................................................................................... 75

E.1 Safety relevant parameters........................................................................................................ 75

E.2 Guidelines for configuring, installing, operating, and service..................................................... 75

Appendix F End of line resistor....................................................................................................77

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1 Introduction

1.1 Overview

In the Rosemount 975UR Ultraviolet Infrared Flame Detector, the infrared (IR) sensor
works at a wavelength of 4.5 µm and is only suitable for hydrocarbon-based fires. The
detector comes with a built-in test (BIT) feature.

All Rosemount 975 series detectors include a heated optical window for improved
performance in icing, snow, and condensation conditions.

The operator can easily adapt detection performance to all environments, applications,
and requirements by changing the detector's configuration parameters. Adjusting these
parameters, as well as performing other maintenance and monitoring tasks, is possible by
means of RS-485 based Modbus® communication or HART® communication (in models
with 0-20 mA output).

The detector enclosure is ATEX certified Exd flameproof with an integral, segregated, rear,
Exe terminal compartment (avoiding exposure of the sensors and electronics to
surrounding environment). Hence the combined approval:

Ex II 2G D
Ex db eb op is IIC T4 G
Ex tb op is IIIC T96 °C Db
(-55 °C ≤ Ta ≤ +75 °C)
or
Ex II 2G D
Ex db eb op is IIC T4 Gb
Ex tb op is IIIC T106 °C Db
(-55 °C ≤ Ta ≤ +85 °C)
The flame detector is designed to operate as a stand-alone unit directly connected to an

alarm system or an automatic fire extinguishing system. The detector can also be part of a
more complex system where many detectors and other devices are integrated through a
common control unit.

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1.2 Ordering information

The Rosemount 975UR is provided in various configurations depending on:

• Output configurations

• Temperature

• Housing style

• Product certifications

The configuration detail is included in the product part
number on the product label and takes the form:
Rosemount 975UR-XXXXXXX, where XXXXXXX defines the
model according to the above requirements.

To modify the default or pre-ordered configuration and
perform maintenance tasks, please refer to the following
manuals: Rosemount 975 Flame Detector HART

Communication Manual (00809-0200-4975) or WinHost
Configuration and Diagnostic Software for Rosemount 975
Flame Detectors (00809-0300-4975).

CONFIGURE > VIEW PRODUCT >

Typical model number: 975UR1A6A1A1
The starred offerings (★) represent the most common

options and should be selected for best delivery. The non­starred offerings are subject to additional delivery lead
time.

1.2.1 Product description

Code Description

975 975 flame detector ★

1.2.2 Technology

Code Description

MR Multi-spectrum infrared ★

HR Multi-spectrum infrared hydrogen ★

UF Ultra fast ultraviolet infrared ★

UR Ultraviolet infrared ★

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1.2.3 Output configuration

Code Outputs Fault relay Alarm relay Auxiliary relay Current type

1A Analog/HART®/

RS-485/relays
(fault, alarm)

2A Analog/HART/

RS-485/relays
(fault, alarm)

3A Analog/HART/

RS-485/relays
(fault, alarm)

1R RS-485/relays

(fault, alarm,
auxiliary)

2R RS-485/relays

(fault, alarm,
auxiliary)

Normally closed Normally open N/A Sink ★

Normally closed Normally open,

normally closed

Normally open Normally open,

normally closed

Normally closed Normally open Normally open N/A ★

Normally open Normally open Normally open N/A ★

N/A Source ★

N/A Source ★

1.2.4 Housing style

Code Material Conduit entry

(1)

6A

8A

Aluminum ¾-in. national pipe thread (NPT) ★

(1)

Aluminum M25 ★

6S Stainless steel ¾-in. NPT ★

8S Stainless steel M25 ★

(1) Aluminum housing is not available in FM/CSA product certification.

1.2.5 Temperature

Code Description

1 167 °F (75 °C) ★

2 185 °F (85 °C) ★

1.2.6 Product certifications

Code Description

A1 ATEX and IECEx flameproof ★

A2 FM and CSA flameproof ★

E2 InMetro flameproof ★

EM Technical Regulations Customs Union (EAC) flameproof ★

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1.2.7 Spare parts and accessories

Part number Description

00975-9000-0001 Tilt mount ★

00975-9000-0002 Duct mount ★

00975-9000-0003 Weather cover (plastic) ★

00975-9000-0004 Weather cover (stainless steel) ★

00975-9000-0005 Air shield ★

00975-9000-0007 2-in. (50.8 mm) pipe mount ★

00975-9000-0008 3-in. (76.2 mm) pipe mount ★

00975-9000-0010 Flame simulator kit (for Rosemount 975UF and

975UR)

00975-9000-0011 USB RS-485 harness kit ★

00975-9000-0012 Spare battery pack for use with flame simulator ★

00975-9000-0014 4-in. (101.6 mm) pipe mount ★

00975-9000-0015 Spare battery charger for use with flame simulator ★

1.2.8 Output configurations

Output
configuration

1A Power Manual built-

2A Power Manual built-

3A Power Manual built-

1R Power Manual built-

2R Power Manual built-

Connections provided

in test

in test

in test

in test

in test

Fault relay
N.C.

Fault relay
N.C.

Fault relay
N.O.

Fault relay
N.C.

Fault relay
N.O.

Alarm relay
N.O.

Alarm relay,
N.O., N.C.

Alarm relay
N.O., N.C.

Alarm relay
N.O.

Alarm relay
N.O.

0-20 mA sink RS-485 HART

0-20 mA
source

0-20 mA
source

Auxiliary
N.O.

Auxiliary
N.O.

RS-485 HART

RS-485 HART

RS-485 N/A

RS-485 N/A

★

®

NOTICE

Output configuration 1A is default. You can change the mA sink output to source type,
with a link between terminals 1 and 8. You cannot change any other output configurations
on site.

For example, product number Rosemount 975UR3A8S2A1 has the following options:

• Output configuration: 3A (analog/HART/RS-485/relays, fault N.O., alarm N.O./N.C.)

• Housing style: 8S (stainless steel - M25 conduit entry)

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• Temperature: 2 (185 °F [85 °C])

• Approvals: A1 (ATEX and IECEx flameproof)

NOTICE

Check your specific part numbers against the information in Checking the product type.

1.3 Features and benefits

The flame detector has the following features and benefits.

• UV/IR dual sensor.

• Built-in-test (BIT): manual and automatic (see Built-in test (BIT)).

• Heated window: prevents effects of icing, snow, and condensation.

• Electrical interface:
— Dry contact relays

— Communication network RS-485
— 0-20 mA output

• HART® protocol: communication protocol (see HART® protocol).

• Exde: integral junction box for easy wiring.

• SIL-2: TÜV approved.

• Hazardous area certification: ATEX, IECEx, and FM

• Functionality approval:
— EN54-10 approved by VdS

— FM approved per FM3260

• Accessories are approved as part of ATEX and IECEx approval.

1.4 Principles of operation

1.4.1 Detection principles

The Rosemount Rosemount 975UR flame detector is an electronic device designed to
sense the occurrence of fire and flames and subsequently activate an alarm or an
extinguishing system directly or through a control circuit.

The UV/IR radiation flame detector is a dual spectrum optical detector sensitive to two
separate ranges of the radiation spectrum, both of which are present in fires. The detector
monitors the protected volume by measuring the radiation intensity in it within two
frequencies of the electromagnetic spectrum, namely the ultraviolet (UV) and the infrared
(IR).

The detector integrates two dependent channels in which appropriate detection pulses
are registered and further analyzed for frequency, intensity, and duration.

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Sensing elements

The IR sensor in the Rosemount Rosemount 975UR is sensitive to radiation over a range of

4.4 to 4.6 µm spectral band where the CO2 has a unique spectral peak that enables it to

detect the combustion product of any organic substance.
The UV sensor is sensitive to radiation over the range of 0.185 to 0.260 µm. The UV

channel incorporates a special logic circuit that eliminates false alarms caused by solar
radiation and other non-fire UV sources. Furthermore, the UV channel's sensitivity is
stabilized over the working temperature range.

Detection levels

Simultaneous detection of radiation in both the UV and the IR channels having an intensity
that exceeds the detector's preset warning level results in a Warning signal.

Simultaneous detection of radiation in both the UV and the IR channels having an intensity
that exceeds the detector's preset alarm levels results in an Alarm signal.

Simultaneous detection of radiation in both the UV and the IR channels having an intensity
that exceeds the detector's preset flash-fire detection level results in an immediate Alarm

signal.
As the present dual range and level of radiation as well as the flickering pattern are

characteristics of real fire, all other radiation sources apart from actual fire are not
detected, thus avoiding false alarms.

1.4.2 Heated optics

The flame detector uses heated optics. The heater increases the temperature of the
optical surface by 5 to 8 °F (3 to 5 °C) above the ambient temperature to improve
performance in icing, condensation, and snow conditions.

The heated optics can be set to one of the following:

• Off, not operating.

• On continuously.

• Automatic, per temperature change (default): the operator can define the start

temperature below which the window is heated. The default is 41 °F (5 °C). The
operator can define this temperature between 32 °F (0 °C) and 122 °F (50 °C). The
heating stops when the temperature is 27 °F (15 °C) above the start temperature.

For more information, see Configure the detector.

1.4.3 HART® protocol

The flame detector uses the HART protocol.
HART communication is a bi-directional industrial field communication protocol used to

communicate between intelligent field instruments and host systems. HART is the global
standard for smart process instrumentation, and the majority of smart field devices
installed in plants worldwide are HART-enabled. HART is available in output configurations
1A, 2A, and 3A (see Output configuration).

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HART technology is easy to use and very reliable.
Through the HART connection, you can do the following:

• Detector setup

• Detector troubleshooting

• Detector health and status

For more details, refer to Rosemount 975 HART Communication Manual

(00809-0200-4975).

1.4.4 RS-485 Modbus

For more advanced communications, the flame detector has an RS-485 Modbus­compatible output that provides data communication from a network (up to 247
detectors) to a host computer or universal controller for central monitoring. This feature
allows for reduced installation costs, easy maintenance, and local or remote diagnostic
tools.

®

1.4.5 Product certifications

The flame detector has the following certifications:

• ATEX, IECEx

• FM, CSA

• SIL-2 (TÜV)

• EN54-10

• InMetro (UL)

• TR CU/EAC

ATEX, IECEx

The flame detector is certified to:
ATEX per SIRA 15ATEX1364X and IECEx per IECEx SIR 15.0138X.

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Ex II 2G D
Ex db eb op is IIC T4 Gb
Ex tb op is IIIC T96 °C Db
(-55 °C ≤ Ta ≤ +75 °C)
or
Ex II 2G D
Ex db eb op is IIC T4 Gb
Ex tb op is IIIC T106 °C Db
(-55 °C ≤ Ta ≤ +85 °C)

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The accessories: tilt mount (PN 00975-9000-0001), weather cover (PN 00975-9000-0003
[plastic] and PN 00975-9000-0004 [stainless steel]), duct mount (PN 00975-9000-0002),
and air shield (PN 00975-9000-0005), are included in the approval.

This product is available to use in hazardous zones 1 and 2 with IIC gas group vapors
present and zones 21 and 22 with IIIC dust type present.

FM, CSA

The flame detector is certified to FM and CSA explosion proof and functionality per
FM3260.

• Class I, Division 1, Groups B, C, and D, T5 Ta = 85 °C.

• Dust ignition proof - Class II/III Division 1, Groups E, F, and G.

• Ingress protection - IP67, IP66, NEMA 250 Type 6P

• For more details, see FM Report Project ID3029553 and CSA Report No. 2451134.

SIL-2 (TÜV)

The flame detector is certified to SIL-2 requirement per IEC 61508A, Chapter 3.5.12.
The alert condition according to SIL-2 can be implemented by:

• Alert signal via 0-20 mA current loop

or

• Alert signal via alarm relay and fault relay

For more details and guidelines for configuring, installing, operating, and service, see SIL-2

features and TUV Report No. 968/FSP 1223.

EN54-10

The flame detector is approved per EN54-10 and CPD.

• The detector has been tested and approved per EN54-10 Vds.

• This test includes functional test, environmental test, EMI/EMC test, and software

check.

• For more details, see SIL-2 (TÜV) and TÜV Report Number 968/EZ 348.

InMetro (UL)

The flame detector is in compliance with the following standards as of May 18, 2010:

• ABNT NBR IEC 60079-0

• ABNT NBRIEC 60079-1

• ABNT NBR IEC 60079-7

• ABNT NBR IEC 60079-18

• ABNT NBR IEC 60079-31

• INMETRO decree No. 179

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For further details, see the Certificate of Compliance No. UL-BR 16.065XX.

TR CU/EAC

The flame detector is in compliance with the standard TR CU 012/2011 per:

1Ex db eb op is IIC T4 Gb X
Ex tb op is IIIC T96 °C Db X

-55 °C ≤ Ta ≤ +75 °C

or
1Ex db eb op is IIC T4 Gb X
Ex tb op is IIIC T106 °C Db X

-55 °C ≤ Ta ≤ +85 °C

For more details, see TR CU certificate No. TC RU C-US MЮ 62.B05535.

1.5 Performance considerations

1.5.1 Detection sensitivity

Detection sensitivity is the maximum distance at which the detector reliably detects a
specific size of fire and typical type of fuel (standard fire).

Standard fire

Defined as 1 ft.2 (0.1 m2) n-heptane pan fire with maximum wind speed of 6.5 ft./sec
(2 m/sec).

Sensitivity ranges

The detector has two response levels:

• Warning (Pre-alarm)

• Alarm

The detection distance for the Alarm level is 93 ft. (28 m) from a standard fire.

The detection distance for the Warning level is approximately 10 percent higher than the

Alarm distance.

For some typical ambient conditions, the Zeta parameter as defined in NFPA 72 for the
detector is 0.005 (1/meter).

Note

Zeta parameters may vary significantly with changes in temperature, air pressure,
humidity, visibility conditions, etc.

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Other fuels

The detector reacts to other types of fire as follows:

• The baseline fire refers to n-heptane 1 ft.2 (0.1 m2) and is defined as 100 percent

sensitivity.

• For fuel fire: standard pan fire size: 1 ft.2 (0.1 m2)

• For gas flame: 30 in. (0.75 m) high, 10 in. (0.25 m) wide plume fire

• Maximum response time: 10 sec.

Table 1-1: Fuel Sensitivity Ranges

Type of fuel Max. distance (ft. / m)

Gasoline 93 / 28

n-heptane 93 / 28

JP5 70 / 21

Kerosene 70 / 21

Diesel fuel 70 / 21

IPA 70 / 21

(1)

LPG

Polypropylene 60 / 18

Methanol 57 / 17

Methane

Ethanol 95% 57 / 17

Paper 33 / 10

(1) 30 in. (0.75 m) high, 10 in. (0.25 m) wide plume fire

1

60 / 18

60 / 18

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1.5.2 Field of view

For Rosemount 975MR, 975UF, and 975UR

Figure 1-1: Horizontal Field of View

A. Relative range

Horizontal: 100 °

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Figure 1-2: Vertical Field of View for Rosemount 975UF and 975UR

A. Relative range

• +50 ° (down)

• -40 °(up)

1.5.3 False alarms prevention

To prevent false alarms, the detector will not alarm or react to the radiation sources
specified in the table below.

Table 1-2: Immunity to False Alarm Sources

Radiation source Immunity distance ft. (m)

Indirect or reflected sunlight IAD

Vehicle headlights (low beam) conforming to
MS53023-1

Incandescent frosted glass light, 300 W IAD

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Table 1-2: Immunity to False Alarm Sources (continued)

Radiation source Immunity distance ft. (m)

Fluorescent light with white enamel reflector,
standard office or shop, 70 W (or two 35 W)

Electric arc (15/32 in. [12 mm] gap at 4,000 Vac,
60 Hz)

Arc welding (5/16 in. [6 mm] rod; 210 A) 9.8 (3)

Ambient light extremes (darkness to bright light
with snow, water, rain, desert glare, and fog)

Bright colored clothing, including red and safety
orange

Electronic flash (180 W-seconds minimum
output)

Movie light, 625 W quartz DWY lamp (Sylvania
S.G. - 55 or equivalent)

Blue-green dome light conforming to
M251073-1

Flashlight (MX 99 I/U) IAD

Radiation heater, 3,000 W IAD

Radiation heater, 1,000 W with fan IAD

Quartz lamp (1,000 W) 12 (4)

Mercury vapor lamp IAD

IAD

IAD

IAD

IAD

IAD

> 6.5 (2)

IAD

Grinding metal 3.3 (1)

Lit cigar IAD

Lit cigarette IAD

Match, wood, stick, including flare up 3.3 (1)

1. IAD: Immune at any distance.

2. All sources are chopped from 0 to 20 Hz.

1.5.4 Visual indicators

One three-color LED indicator is located inside the detector window, as shown in Figure

1-3. The detector statuses are listed in Table 1-3.

Table 1-3: LED Indications

Detector status LED color LED mode

Fault, BIT Fault Yellow 4 Hz - flashing

Normal Green 1 Hz - flashing

Warning Red 2 Hz -flashing

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Table 1-3: LED Indications (continued)

Detector status LED color LED mode

Alarm Red Steady

Figure 1-3: Indication LED

A. Indicator LED

1.5.5 Output signals

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Outputs are available according to the default configuration or the wiring options selected
for the detector.

Determine the outputs of your model according to Table 1-4.
The detector incorporates several types of output suitable to different control systems.

• 0-20 mA (stepped) with HART

• Relays (alarm, fault, auxiliary)

• RS-485 Modbus

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Table 1-4: Available Output Types

Output type Version Detector status

Alarm relay 975UR - output configurations

Auxiliary relay 975UR - output configurations

Fault relay 975UR - output configurations

0-20 mA current output 975UR - output configuration

RS-485 All versions Modbus protocol

1.5.6 Detector status

1AXXXXX, 1RXXXXX, and
2RXXXXX

975UR - output configurations
2AXXXXX and 3AXXXXX

1RXXXXX and 2RXXXXX

1AXXXXX, 2AXXXXX, and
1RXXXXX

975UR - output configurations
3AXXXXX and 2RXXXXX

1AXXXXX

975UR - output configurations
2AXXXXX and 3AXXXXX

The relay is N.O.

The relay is N.O. and N.C.

The relay is N.O.

The relay is N.C. energized.

The relay is N.O. energized.

Sink with the HART protocol
(can be changed to Source - see

Figure B-3, Figure B-4, and
Figure B-5).

Source with the HART protocol

The possible detector function statuses are listed in the table below. Use HART® or
Modbus® to see a more detailed fault analysis.

Table 1-5: Detector Statuses

Status Description

Normal Normal operation.

BIT Built-in test being performed.

Warning Fire detected - changed to Warning (pre-alarm state).

Alarm Fire detected - changed to Fire Alarm state.

Latched alarm (optional) The alarm outputs remain latched on following detection of a fire

that has already been extinguished.

BIT fault A fault is detected during built-in test sequence or other electric

failure. The detector will continue to detect for fire.

Fault A fault is detected when the power supply is too low or due to a

software fault or electrical failure. The detector will not detect fire
in this condition.

In each state, the detector activates different outputs, as specified in Table 1-6.

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Table 1-6: Output Signals vs. Detector State

Detector state LED indicator LED mode Alarm relay Auxiliary relay Fault relay mA output

Normal Green 1 Hz Off Off On 4 mA

On

(1)

(1)

(1)

On 16 mA

On 20 mA

Off 16 mA

Warning Red 2 Hz Off On

(2)

Alarm

(3)

Latch

BIT Fault

Warning at BIT
Fault

(4)

Red Constant On On On 20 mA

Red Constant On Off On 20 mA

Yellow 4 Hz Off Off Off 2 mA

Red 2 Hz Off On

Alarm at BIT
Fault

Fault Yellow 4 Hz Off Off Off 0 mA

(1) The auxiliary relay can be activated at the Warning level or Alarm level, depending on programmed function.
(2) The alarm outputs are activated while alarm conditions exist and will stop approximately five seconds after a fire is no

longer detected.

(3) The Alarm state can be optionally latched via programmed function. (Default is non-latching).
(4) The detector will remain in BIT Fault state until it has passed a successful built-in test.

Red Constant On On Off 20 mA

Note

The outputs depend on the output configurations.

Optional latching

Alarms are set as non-latching by default. However, the detector includes a latched alarm
output capability, which operates according to the programmed function.

If selected, upon detection of a fire, the detection signal is latched until the operator
manually resets the detector (disconnecting the power supply or performing a manual
built-in test [see Manual built-in test]).

Latching affects the alarm relay, 0-20 mA output, and the alarm LED. The auxiliary relay is
latched only when the programmable function Auxiliary Relay is set to Yes.

NOTICE

The auxiliary relay is available only in models with output configurations - 1RXXXXX and
2RXXXXX.
The 0-20 mA is available only in models with output configurations - 1AXXXXX, 2AXXXXX,
and 3AXXXXX.

1.6 Internal detector tests

The detector performs two types of self-tests:

• Continuous feature test

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• Built-in test (BIT)

1.6.1 Continuous feature test

The detector is supplied with default settings, including a continuous feature test.
During normal operation, the detector tests itself continuously and indicates a fault if a

failure is found.
The detector continuously tests:

• Input voltage level

• All internal regulator voltage level

• Voltage level status of sensor and sensor circuitry for noise or disconnection in the

electronic circuitry

• 0-20 mA level output

• Relays and heater operation

• Processor watch dog

• Software

• Memory

• Oscillator frequency

Response to a fault indication

If a failure is found, the detector indicates it by:

• Fault relay:
— Opens in output configurations 1A, 2A, and 1R

— Closes in output configurations 3A and 2R

• 0-20 mA: indicates fault (0 mA or 2 mA) in output configurations 1A, 2A, and 3A

• LED - yellow flashes (4 Hz)

• Correcting the fault

The fault indications remain until the detector's power is removed. The fault indications
return if the fault is still found when power is restored.

1.6.2 Built-in test (BIT)

The detector's built-in test (BIT) also checks the following:

• Electronics circuitry

• Sensors

• Window cleanliness

The detector can be set to perform the built-in test in the following modes:

• Automatically and manually

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• Manually only

NOTICE

In a manual built-in test, the outputs may also be tested; apply control system inhibit if
this could initiate other systems.

How the built-in test operates

• The detector's status remains unchanged if the result of a built-in test is the same as

the current status (Normal or BIT Fault).

• The detector's status is changed (from Normal to BIT Fault or vice versa) if the built-in

test differs from the current status.

NOTICE

In BIT Fault status, the detector can continue to detect a fire.

Automatic built-in test

The detector automatically performs a built-in test every fifteen minutes. A successful
built-in test sequence does not activate any indicator.

All outputs of built-in test results function as described in Table 1-7 and Table 1-8, and the
built-in test is automatically executed every one minute.

This continues until a successful built-in test occurs, when the detector resumes normal
operation.

Table 1-7: Results of a Successful Built-in Test

Output Result

Fault relay • Output configurations 1A, 2A, and 1R:

0-20 mA output Output configurations 1A, 2A, and 3A: Normal

Power LED Green, flashing, 1 Hz on (Normal)

Table 1-8: Results of an Unsuccessful Built-in Test

Output Result

Fault relay • Output configurations 1A, 2A, and 1R:

remain CLOSED

• Output configurations 3A and 2R: remain

OPEN

(4 mA)

change to OPEN

• Output configurations 3A and 2R: change to

CLOSED

0-20 mA output Output configurations 1A, 2A, and 3A: BIT Fault

(2 mA)

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Table 1-8: Results of an Unsuccessful Built-in Test (continued)

Output Result

Power LED Yellow, flashing, 4 Hz

BIT procedure Performed every one minute

Manual built-in test

To intiate the built-in test manually, momentarily connect Terminal 3 to Terminal 2 (or a
switch across these terminals in a safe area).

The results of a successful and unsuccessful manual built-in test are listed in Table 1-9 and

Table 1-10.

Table 1-9: Results of a Successful Manual Built-in Test

Output Result

Fault relay • Output configurations 1A, 2A, and 1R: remain CLOSED

(Normal).

• Output configurations 3A and 2R: remain OPEN (Normal).

Alarm relay Activated for three seconds (only when the function Alarm BIT is

set to YES).

Auxiliary relay For output configurations 1R and 2R, is activated for three

seconds (only when the function Auxiliary BIT is set to YES).

0-20 mA output Output configurations 1A, 2A, and 3A:

• Initiates 20 mA only when the function Alarm BIT is set to

YES.

• Initiates 16 mA when the function Auxiliary BIT is set to YES

and the function Alarm BIT is set to NO.

Power LED Green, flashing, 1 Hz

Table 1-10: Results of an Unsuccessful Manual Built-in Test

Output Result

Fault relay • Output configurations 1A, 2A, and 1R: change to OPEN.

• Output configurations 3A and 2R: change to CLOSED.

0-20 mA output Output configurations 1A, 2A, and 3A: indicates BIT Fault (2 mA)

Power LED Yellow, flashing, 4 Hz

Manual built-in test only selected

The built-in test is initiated manually by momentarily selecting Terminal Number 3 with
Terminal Number 2 or a switch across these terminals in a safe area.

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2 Installing the detector

This chapter provides basic guidelines for installing the detector. It does not attempt to
cover all of the standard practices and codes of installation. Rather, it emphasizes specific
points of consideration and provides some general rules for qualified personnel. Wherever
applicable, special safety precautions are stressed.

2.1 General guidelines

To ensure optimal performance and an efficient installation, consider the following
guidelines:

• Sensitivity: To determine the level of sensitivity, consider the following:
— Size of fire at the required distance to be detected

— Type of flammable materials

• Wiring:
— The wire gauge must be designed according to the distance from the detector to

the controller and the number of detectors on the same power line. See Wiring

instructions.

— To fully comply with EMC directive and protect against interference caused by RFI

and EMI, the cable to the detector must be shielded, and the detector must be
grounded. Ground the shield at the detector end.

• Spacing and location: The number of detectors and their locations in the protected

area are determined by:

— Size of the protected area
— Sensitivity of the detectors
— Obstructed lines of sight
— Cone of view of the detectors

• Environment:
— Dust, snow, or rain can reduce the detector's sensitivity and require more

maintenance activities.

— The presence of high intensity flickering IR sources may affect sensitivity.

• Aiming the detector:
— Aim the detector toward the center of the detection zone and make sure the view

of the protected area is completely unobstructed.

— Whenever possible, tilt the detector face down at a 45-degree angle to maximize

coverage and prevent accumulation of dust and dirt.

— Take into account all conceivable considerations regarding detection location

before starting an installation.

Installations must comply with National Fire Protection Agency (NFPA) 72E or any other
local and international regulations and standards, as applicable to flame detectors and
installation of Ex approved products.

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2.2 Unpack

Procedure

1. Upon receipt of your detector, verify that you have received the following contents:

• Delivery form

• Flame detector

• Plastic weather cover

• Quality document

2. Check and record the following:

a) Verify the appropriate purchase order.

b)

Record the model number and serial number of the detector and the
installation date in an appropriate log book.

c) Verify that all components required for the detector installation are readily

available before beginning the installation.

Postrequisites

If the installation is not completed in a single session, secure and seal the detectors and
conduits/cable entries.

2.3 Checking the product type

Confirm your product has the configuration options you ordered.
Check the detailed model number on the label and compare this information with the

descriptions contained in Ordering information.

2.4 Required tools

The operator can install the detector using general purpose tools and equipment.

Table 2-1 lists the specific tools required to install the detector.

Table 2-1: Required Tools

Tool Function Comments

Hex key 3/16-in. Open and close the detector

cover (for wiring).

Hex key ¼-in. Mount the detector on the tilt

mount.

Part of the kit

Part of the kit

Flat screwdriver 6 mm Connect ground terminal. Standard tool

Flat screwdriver 2.5 mm Connect wires to the terminal

blocks.

Hex key 5/16-in. Scrw detector plug. Part of the kit

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For wiring, use color-coded conductors or suitable wire markings or labels. You may use 12
to 20 AWG (0.5 mm2 to 3.5 mm2) wires for site wiring. Select wire gauge based on the
number of detectors used on the same line and the distance from the control to the
ground unit, in compliance with specifications. See General instructions for electrical

wiring.).

2.5 Certification instructions

WARNING

Flammable

Do not open the detector, even when isolated, in a flammable atmosphere.

Use the following certification instructions:

• The cable entry point may exceed 167 °F (75 °C). Take suitable precautions when

selecting the cable.

• The equipment may be used with flammable gases and vapors with apparatus groups

IIA, IIB, and IIC:

— T5 in the ambient temperature range: -67 °F (-55 °C) to 167 °F (75 °C)
— T4 in the ambient temperature range: -67 °F (-55 °C) to 185 °F (85 °C)

• Only suitably trained personnel should install the detector, in accordance with the

applicable code of practice, such as EN 60079-14:1997.

• Only suitably trained personnel should inspect and maintain the detector, in

accordance with the applicable code of practice, such as EN 60079-17.

• Only suitably trained personnel should repair the detector, in accordance with the

applicable code of practice, such as EN 60079-19.

• The certification of this equipment relies upon the following materials used in its

construction:

— Enclosure: 316L stainless steel or aluminum
— Window: sapphire glass

• If the equipment is likely to come into contact with aggressive substances, take

suitable precautions to prevent it from being adversely affected, thus ensuring that the
type of protection provided by the equipment is not compromised.

— Aggressive substances: acidic liquids or gases that may attack metals or solvents

that may affect polymeric materials.

— Suitable precautions: regular checks as part of routine inspections or establishing

from the material's data sheets that it is resistant to specific chemicals.

• To maintain the IPx6 and Type 6P ingress protection ratings, NPT plugs shall be

torqued to a value of 90 Nm (67 lbft). In addition, a suitable thread sealant, such as
PTFE tape, shall be applied to NPT threads for submersion applications.

Refer to Product certifications for more information about product certifications.

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2.6 Installing cables

When installing cables for the flame detector, consider the following:

• Ensure all cables to the detector are well shielded in order to comply with EMC

requirements.

• The end user must use suitable rated blanking plugs for all unused entries.

• Ground the detector to the nearest ground point (not more than 9.8 ft. (3 m) from the

flame detector).

• Install the detector with the cable entries and conduit pointed downwards.

2.6.1 Installing conduit

The conduit used for the cabling must comply with the following:

• To avoid water condensation in the detector, install the detector with the conduits that

include drain holes pointed downwards.

• When using the optional tilt mount, use flexible conduits for the last portion

connecting to the detector.

• For installation in atmospheres as defined in group B of the National Fire Protection

Agency (NFPA) 72E, seal the conduit inlets.

• When pulling the cables through the conduits, ensure that they are not tangled or

stressed. Extend the cables about 12 in. (30 cm) beyond the detector location to
accommodate wiring after installation.

• After pulling the conductor cables through the conduits, perform a continuity test.

2.7 Installing the tilt mount (PN 00975-9000-0001)

The tilt mount (PN 00975-9000-0001) enables the detector to rotate up to 60 degrees in
all directions.

Figure 2-1 shows the detector mounted on the tilt mount.

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Figure 2-1: Detector with Tilt Mount

A. Cover bolts

B. Back cover
C. Tilt mount plate
D. Horizontal locking screw

E.

Tilt mount

F. Vertical locking screw
G. Detector holding screw
H. Tilt mount holding plate

I. Conduit/cable inlet
J. Detector assembly

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2.7.1 Assemble the tilt mount

Figure 2-2: Tilt Mount Assembly

A. Tilt holding plate

B. Tilt mount
C. Horizontal locking screw
D. Vertical locking screw

E.

Detector holding plate

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Figure 2-3: Tilt Mount Assembly Dimensions

To install the tilt mount:

Procedure

1. Place the tilt mount in its designated location and secure it with four (4) fasteners

through four (4) holes 0.14 in. (7 mm) in diameter. Use the four (4) screws and
spring washers according to the kit.

Refer to Figure 2-3,

Note

You do not have to remove the tilt mount when removing the detector for
maintenance purposes.

2. Unpack the detector.

3. Place the detector with its conduit/cable entries pointing downwards on the

holding plate of the tilt mount. Secure the detector with 5/16-in. 18 UNC x 1-in.
screw to the tilt mount.

4. Release the horizontal and vertical locking screws using the supplied 3/16-in. hex

key, such that the detector can be rotated. Point the detector towards the
protected area and ensure the view of the area is unobstructed. Secure the detector
in position by tightening the locking screws on the tilt mount.

The detector is now correctly located, aligned, and ready to be connected to the system.

Table 2-2, and Table 2-3.

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Postrequisites

Refer to Connect the detector.

2.8 Connect the detector

To connect the detector to the electrical cables:

Procedure

1. Disconnect the power to the electrical cables.

2. Remove the back cover of the detector by removing three socket head screws in the

cover bolts.
Refer to Figure 2-1
The terminal chamber is now revealed.

3. Remove the protective plug mounted on the detector conduit/cable entry; pull the

wires through the detector inlet.

4. Use a ¾-in. - 14 national pipe thread (NPT) explosion-proof conduit connection or

M25 x 1.5 flameproof gland to assemble the cable/conduit to the detector.

5. Connect the wires to the required terminals on the terminal board according to the

wiring diagram.
See Figure 2-4 and Table 2-2.

.

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Figure 2-4: Detector with Cover Removed

Rosemount 975UR 35

A. Terminal chamber

Terminals

B.
C.

Internal earth terminal
Earth terminal

D.

E.

Detector holding screw

F. Conduit/cable entry
G. See Table 2-2.
H. Alarm relay (C)

I. Alarm relay (normally open)
J. Fault relay (C)

K. Manual built-in test (BIT)

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6. Connect the grounding wire to the ground screw outside the flame detector (earth
terminal).

The detector must be well-grounded to earth ground.

7. Verify the wiring.

CAUTION

Equipment damage

Improper wiring may damage the detector.

8. Check the wires for secure mechanical connection and press them neatly against
the terminal to prevent them from interfering while closing the back cover.

Refer to Figure 2-4.

9. Place and secure the detector's back cover by screwing the three (3) socket-head
screws in the cover bolts.

Refer to Figure 2-1.

2.8.1

Table 2-2: Rosemount 975UR Output Configurations

Wire terminal
number

1 +24 Vdc +24 Vdc +24 Vdc +24 Vdc +24 Vdc

2 0 Vdc 0 Vdc 0 Vdc 0 Vdc 0 Vdc

3 Manual built-in

4 Fault relay

5

6 Alarm relay N.O. Alarm relay N.O. Alarm relay N.O. Alarm relay N.O. Alarm relay N.O.

7 Alarm relay C Alarm relay C Alarm relay C Alarm relay C Alarm relay C

8 0-20 mA in Alarm relay N.C. Alarm relay N.C. Auxiliary N.O. Auxiliary N.O.

9 0-20 mA out

Verify the detector wiring

The flame detector has five output configurations within the Exde integral terminal
section of the enclosure. There are twelve terminals labeled 1 - 12.

For more information on the output configurations, see Wiring instructions.

Table 2-2 describes the function of each terminal for all the output configurations.

1A (default) 2A 3A 1R 2R

test

normally clsed
(N.C.)

Manual built-in
test

Fault relay N.C. Fault relay

(1)

0-20 mA out

(1)

Manual built-in
test

normally open
(N.O.)

0-20 mA out

Manual built-in
test

Fault relay N.C. Fault relay N.O.

(1)

Auxiliary C Auxiliary C

Manual built-in
test

10 RS-485 + (1) RS-485 + (1) RS-485 + (1) RS-485 + (1) RS-485 + (1)

11 RS-485 - (1) RS-485 - (1) RS-485 - (1) RS-485 - (1) RS-485 - (1)

12 RS-485 GND RS-485 GND RS-485 GND RS-485 GND RS-485 GND

(1) Available with the HART® protocol.

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Output configuration notes

• RS-485 is used for network communication, as specified in RS-485 communication

network, (terminals 10, 11, and 12) and to connect (in safe areas) to PC/laptop for

configuration/diagnostics.

• Alarm relay
— Normally open (N.O.) in output configuration 1A, 1R, and 2R

— N.O. and normally closed (N.C.) in output configuration 2A and 3A

• 0-20 mA is Sink in output configuration 1A and Source in output configurations 2A and

3A.

• 0-20 mA output configurations 1A, 2A, and 3A are available with the HART® protocol.

• In output configuration 1A, link terminals 1 and 8 to change the mA output to Source.

• The fault output is N.C. energized SPST relay. The contacts are closed when the

detector is in its normal operational condition in output configurations 1A, 2A, and 1R
and available as N.O. energized in output configurations 3A and 2R.

• The auxiliary output is N.O. energized (SPST) relay. The auxiliary relay may act in

parallel with the alarm relay to activate another external device, or it may provide a
warning signal, depending on the function configuration.

2.9 Configure the detector

You can reprogram the function setup using the RS-485 connection or using the HART
protocol as follows:

• USB RS-485 harness kit (PN 00975-9000-0011): The USB RS-485 harness kit with

RS-485/USB converter, used with the Rosemount host software, enables you to
connect to any available PC or laptop to reconfigure settings or perform diagnostics on
all Rosemount 975 series flame detectors.

Refer to the WinHost Configuration and Diagnostic Software for Rosemount 975 Flame

Detectors Manual (00809-0300-4975) for programming instructions when using the

USB RS-485 harness kit.

• HART protocol: Refer to the Rosemount 975 Flame Detector HART Communication

Protocol Manual (00809-0200-4975) for programming instructions.

These functions enable you to set:

• Alarm delay

• Address setup

• Mode of operation

• Heated optics operation

The factory default settings listed for each function are:

• Alarm delay: 3 sec

®

• Alarm latch: No

• Auxiliary relay: No

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• Automatic BIT: Yes

• Alarm BIT: No

• Auxiliary BIT: No

• Heated optics: Auto

• Temperature: 41 °F (5 °C)

2.9.1 Alarm delay

The flame detector is equipped with an alarm delay option, which provides programmable
time delay with settings at:

• Antiflare

Other delay settings are available:

• 0, 3, 5, 10, 15, 20, or 30 seconds

When an alarm (detection) level condition occurs, the flame detector delays the execution
of the alarm outputs by the specified period of time. The detector then evaluates the
condition for three seconds. If the alarm level is still present, the detector activates the
alarm outputs. If this condition no longer exists, the detector returns to its standby state.

(1)

The alarm delay option affects the output relays and the 0-20 mA output. The LEDs and
outputs indicate warning levels during the delay time only if the fire condition exists.

2.9.2 Address setup

The flame detector provides up to 247 addresses that can be changed with the RS-485
communication link or the HART® communication protocol.

2.9.3 Function setup

You can select the desired functions as detailed in Table 2-3.

Table 2-3: Functions

Function Setting

Alarm latch • Yes: Enable alarm latching.

• No: Disable alarm latching (default).

Auxiliary relay

Automatic BIT • Yes: Perform automatic and manual built-in test

(1)

• Yes: Activate auxiliary relay at warning level.

• No: Activate auxiliary relay at alarm level (default).

(default).

• No: Perform manual built-in test only.

(1) The Antiflare mode is selected to prevent false alarms in locations where fast flares may be present. The time delay for fire

alarms in this mode ranges from 2.5 to 15 seconds (usually less than 10 seconds).

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Table 2-3: Functions (continued)

Function Setting

Alarm BIT • Yes: Successful manual built-in test activates the

alarm relay for approximately three seconds (default).

• No: Successful manual built-in test does not activate

the alarm relay.

Auxiliary BIT

(1) Only available in output configurations 1R and 2R.

(1)

2.9.4 Heated optics

To configure optical window heating, select one of the modes listed below.

• OFF: Optical window surface heating does not operate.

• ON: Optical window surface heating operates continuously.

• AUTO: Optical window surface heating operates according to temperature change.

Specify the start temperature below which the optical window surface is heated to
improve performance in temperatures where snow, ice, and condensation may occur.

In AUTO mode, the default Heat On setting is 41 °F (5 °C). Heating stops when the
temperature is 27 °F (15 °C) above the start temperature.

You can define the start temperature below which the window will be heated. The
temperature can be defined between 32 and 122 °F (0 and 50 °C).

• Yes: Successful manual built-in test activates the

auxiliary relay for approximately three seconds
(default).

• No: Successful manual built-in test does not activate

the auxiliary relay.

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3 Operating the detector

This chapter describes how to power up and test the detector. It also includes some very
important safety checks that you should make before operating the detector.

3.1 Power up

Follow these instructions carefully to obtain optimal performance from the detector over
its life cycle.

To power up the detector:

Procedure

1. Turn on the power.

2. Wait approximately 60 seconds for the detector to finish the startup procedure.
Applying power initiates the following sequence of events:

• The yellow LED flashes at 4 Hz.

• Built-in test is executed.

If successful, the green LED flashes at 1 Hz, and the FAULT relay contacts close; mA
output is 4 mA.

3. Enter Normal mode.

NOTICE

The majority of detectors are used in the default non-latching alarm mode. Only
perform a reset when the latching alarm option has been programmed.

To reset the detector when it is in a Latched Alarm state, do one of the following:

• Disconnect power (terminal number 1 or terminal number 2).

• Initiate a manual built-in test.

3.2 Safety precautions

After powering up, the detector requires almost no attention in order to function properly,
but note the following:

• Follow the instructions in this Reference Manual and refer to the drawings and

specifications.

• Do not expose the detector to radiation of any kind unless required for testing

purposes.

• Do not open the detector housing while power is applied.

• Do not open the electronic compartment. Keep this part closed at all times. It can only

be opened in the factory. Opening the electronic component side invalidates the
warranty.

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• Only access the wiring compartment to wire or remove the detector or access RS-485

terminals for maintenance.

• Disconnect or disable external devices, such as automatic extinguishing systems,

before carrying out any maintenance.

3.2.1 Factory default function settings

Table 3-1 lists the default function configurations supplied with the detector.

Table 3-1: Factory Default Function Settings

Function Value Notes

Alarm delay 3 sec

Alarm latch No

Auxiliary relay No In output configurations 1A,

2A, and 3A, the auxiliary relay is
not available. This function is
not used.

Automatic built-in test (BIT) Yes

Auxiliary built-in test No In output configurations 1A,

Heated optics Auto

Heat on 41 °F (5 °C) The detector starts heating the

In order to change the default function, use:

• USB RS-485 harness kit PN 00975-9000-001

• HART® protocol. Refer to the Rosemount 975 Flame Detector HART Communication

Manual (00809-0200-4975) for instructions.

3.3 Testing procedures

This section describes the proof testing procedure for proper operation of the detector.
Test the detector using the manual built-in test (BIT) or the flame simulator.

The detector performs the internal test continuously and the automatic built-in test every
fifteen minutes; for more details, refer to Built-in test (BIT) .

2A, and 3A, the auxiliary relay is
not available. This function is
not used.

window for any temperature
below this value.

3.3.1 Automatic built-in test

Check that the indicators show normal conditions.
See Power up.

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3.3.2 Manual built-in test

To perform a manual built-in test:

NOTICE

If the function setup Alarm BIT and or Auxiliary BIT are set to YES (default NO), the alarm,
auxiliary relay, and 0-20 mA outputs are activated during a manual built-in test. Therefore,
you must disconnect automatic extinguishing systems or any external devices that may be
activated during the built-in test.

Procedure

1. Verify that the detector is in Normal mode.

2. Initiate the manual built-in test.

The results of succcessful and unsuccessful manual built-in tests are detailed in

Table 1-9 and

Table 1-10.

3.3.3 Test with flame simulator

Use the flame simulator to simulate exposure of the detector to a real fire condition. The
flame simulator exposes the detector to radiation at the required detection level. As a
result, the detector generates a fire alarm signal.

See Flame simulator for more information.

NOTICE

If the detector is exposed to a flame simulator, the alarm and accessory relays and 0-20
mA are activated during the simulation. Therefore, disconnect automatic extinguishing
systems or any external devices that may be activated during this process.

To test the detector with a flame simulator:

Procedure

1. Power up the system and wait up to 60 seconds for the detector to turn to a normal

state.
The power LED turns on.

2. Aim the flame simulator at the target point of the detector, in a way that the

radiation emitted by it is facing directly towards the detector.
See Flame simulator

3. Press Operation once.

After a few seconds, a successful test shows the results shown in Table 3-2.

.

Table 3-2: Results of a Successful Flame Simulator Test

Component Action Notes

0-20 mA Turns to 20 mA For a few seconds and then

returns to 4 mA

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Table 3-2: Results of a Successful Flame Simulator Test (continued)

Component Action Notes

Alarm relay Activated For a few seconds and then

returns to Normal

Auxiliary relay Activated For a few seconds and then

returns to Normal

Fault relay Remains active during the test

LED Red, steady

The detector is now ready for operation.

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4 Maintenance and troubleshooting

This chapter deals with preventative maintenance, describes possible faults in detector
operation, and indicates corrective measures.

Ignoring these instructions may cause problems with the detector and may invalidate the
warranty. Whenever a unit requires service, please contact Emerson or its authorized
distributer for assistance.

4.1 Maintenance

This section describes the basic maintenance steps you should take to keep the detector in
good working condition.

4.1.1 General maintenance procedures

Only suitably qualified personnel who are familiar with local codes and practices should
perform maintenance. Maintenance requires ordinary tools.

Cleaning

Keep the detector as clean as possible. Clean the viewing window and the reflector of the
flame detector periodically.

The frequency of cleaning operations depends upon the local environmental conditions
and specific applications. The fire detection system designer will give his or her
recommendations.

To clean the detector viewing window and reflector:

Procedure

1. Disconnect power to the detector before proceeding with any maintenance,

including window/lens cleaning.

2. Use water and detergent and then rinse the viewing window with clean water.

3. Where dust, dirt, or moisture accumulates on the window, first clean only with a

4.1.2

soft optical cloth and detergent and then rinse with clean water.

Periodic maintenance procedures

In addition to preventive cleaning and maintenance, functionally test the detector every
six months or as dictated by local codes and regulations. Also perform these tests if the
detector has been opened for any reason.

Power-up procedure

Perform the power-up procedure every time power is restored to the system.
Follow the instructions described in Power up.

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Functional test procedure

Perform a functional test of the detector as described in Internal detector tests.

4.1.3 Keeping maintenance records

Emerson recommends that you record maintenance operations performed on a detector
in a log book. The record should include the following:

• Installation date and contractor

• Serial and tag number

• Entries for every maintenance operation performed, including the description of the

operation, date, and personnel ID

If you send a unit to Emerson or a distributer for service, include a copy of the maintenance
records.

4.2 Troubleshooting

This section is intended to be a guide to correct problems that may happen during normal
operation.

4.2.1 Fault relay at N.O.

LEDs off

0-20 mA at 0 mA

Potential cause

No power to the unit.

Recommended actions

1. Check that the correct power is sent to the detector.

2. Check power polarity.

3. Check wiring in the detector.

4.

Send the detector back for repairs.

4.2.2 Fault relay at N.O.

Yellow/amber LED flashes at 4 Hz.

0-20 mA at 0 mA

Potential cause

Detector fault

• Low voltage

• Faulty detector

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Recommended actions

1. Check the voltage at the detector; verify at least 24 V at the detector terminal.

2. Send the detector back for repairs.

4.2.3 Fault relay at N.O.

Yellow/amber LED flashes at 4 Hz.

0-20 mA at 2 mA

Potential cause

Built-in test (BIT) fault: faulty detector

Recommended actions

1.

Clean detector window.

2. Re-power the detector.

3. Replace the detector.

4.2.4 Red LED constantly on

Potential cause

If no fire exists, the detector alarm may be latched.

Recommended action

Reset the detector.

4.2.5 Alarm relay at on

0-20 mA at 20 mA

Potential cause

Alarm condition

Recommended actions

1. Check cause of alarm.

2. If no alarm, re-power the detector.

3. Send the detector back for repairs.

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A Specifications and reference data

A.1 Technical specifications

Table A-1: Technical Specifications

Spectral response UV: 0.185 to 0.260 µm

IR: 4.4 to 4.6 µm

Detection range (at
highest sensitivity
setting for1 ft.2 (0.1
m2) pan fire)

Response time Typically 5 seconds

Adjustable time delay Up to 30 seconds

Sensitivity ranges 1 ft.2 (0.1 m2) n-heptane pan fire from 93 ft. (28 m)

Fields of view Horizontal: 100 °, vertical: 95 °

Built-in test (BIT) Automatic (and manual)

(1) 30 in. (0.75 m) high, 10 in. (0.25 m) wide plume fire

Fuel ft. / m Fuel m / ft

Gasoline 93 / 28 Polypropylene 60 / 18

n-Heptane 93 / 28 LPG 60 / 18

IPA (isopropyl alcohol) 70 / 21 Methane

JP5 70 / 21 Ethanol 95% 57 / 17

Kerosene 70 / 21 Methanol 57 / 17

Diesel fuel 70 / 21 Paper 33 / 10

A.2 Electrical specifications

Operating voltage: 18 - 32 Vdc
Power consumption: Table A-2

(1)

60 / 18

Table A-2: Electrical Specifications

Operating voltage Status All outputs Without 0-20 mA

Power consumption
(max. 24 Vdc)

Maximum current
(max. 24 Vdc)

Rosemount 975UR 49

Normal 1.61 W 1.56 W

Normal when heateron2.28 W 2.16 W

Alarm 2.64 W 2.28 W

Alarm when heater on 3.24 W 2.88 W

Normal 70 mA 65 mA

Normal when heateron95 mA 90 mA

Alarm 110 mA 95 mA

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Table A-2: Electrical Specifications (continued)

Operating voltage Status All outputs Without 0-20 mA

Alarm when heater on 135 mA 120 mA

Power consumption
(max. 18-32 Vdc)

Maximum current (18 ­32 Vdc)

Electrical input protection: The input circuit is protected against voltage-reversed polarity,
voltage transients, surges, and spikes according to MIL-STD-1275B.

A.3 Outputs

Electrical
interface

There are five output configurations. These configurations must be defined
at the factory per the customer order and cannot be changed at the
customer facility.
See General instructions for electrical wiring for the wiring/terminal
diagrams for each option.

Unless otherwise specified, the default is output configuration 1A. The
wiring arrangement is identified on the detector by the part number (see

Ordering information).

Normal 1.95 W 1.85 W

Normal when heateron2.56 W 2.45 W

Alarm 3.04 W 2.56 W

Alarm when heater on 3.68 W 3.2 W

Normal 90 mA 85 mA

Normal when heateron105 mA 100 mA

Alarm 130 mA 115 mA

Alarm when heater on 160 mA 145 mA

• Output configuration 1A: power, RS-485, 0-20 mA (sink), fault relay

(N.C.), alarm relay (N.O.) (see Figure 2-4).

Electrical
outputs

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• Output configuration 2A: power, RS-485, 0-20 mA (source) and HART

protocol, fault relay (N.O.), alarm relay (N.O., N.C.)

• Output configuration 3A: power, RS-485, 0-20 mA (source) and HART

protocol, fault relay (N.O.), alarm relay (N.O., N.C.)

• Output configuration 1R: power, RS-485, fault relay (N.C.), auxiliary relay

(N.O.), alarm relay (N.O.)

• Output configuration 2R: power, RS-485, fault relay (N.O.), auxiliary relay

(N.O.), alarm relay (N.O.)

• Dry contact relays

®

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Table A-3: Contact Ratings

Relay name Type Normal position Maximum

ratings

Alarm SPDT N.O., N.C. 2 A at 30 Vdc

Auxiliary SPST N.O. 2 A at 30 Vdc

Fault (see notes 1
and 2)

1. The fault relay (in output configurations 1A, 2A, and 1R) is
normally energized closed during normal operation of the
detector. The relay is de-energized open if a fault condition or low
voltage situation occurs.

2. In output configurations 3A and 2R, the relay is normally energized
open during normal operation of the detector. The relay is de­energized closed contact if a fault condition or low voltage
situation occurs.

• 0-20 mA current output: The 0-20 mA can be Sink or Source according to

the output configuration (see General instructions for electrical wiring) .
The maximum permitted load resistance is 600 Ω.

Table A-4: 20 mA Current Output

State Output

Fault 0 + 1 mA

Built-in test (BIT) fault 2 mA ± 10%

Normal 4 mA ± 10%

IR 8 mA ± 5%

SPST N.C. or N.O. 2 A at 30 Vdc

UV 12 mA ± 5%

Warning 16 mA ± 5%

Alarm 20 mA ± 5%

Rosemount 975UR 51

• HART protocol: The HART protocol is a digital communication signal at a

low level on top of the 0-20mA. This is a bi-directional field
communication protocol used to communicate between intelligent field
instruments and the host system. HART is available in output
configurations 1A, 2A, and 3A.

Through the HART protocol, the detector can:

— Display setup.
— Reconfigure the setup.
— Display detector status and definition.
— Perform detector diagnostics.

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— Troubleshoot.

For more details, refer to the Rosemount 975 Flame Detector HART

Communication Manual (00809-0200-4975).

• Communication network: The detector is equipped with an RS-485

communication link that can be used in installations with computerized
controllers.

The communication protocol is Modbus® compatible.

— This protocol is standard and widely used.
— It enables continuous communication between a standard Modbus

controller (master device) and a serial network of up to 247 detectors.

Heated
optics

The front window can be heated to improve performance in icing,
condensation, and snow conditions. The heater increases the temperature
of the optical surface by 5 to 8 °F (3 to 5 °C) above the ambient temperature.
The heated optics can be configured in three ways:

• OFF: The optics are not heated.

• ON: The optics are heated continuously.

• AUTO: Operated only when the change of temperature requires heating

(default).

In AUTO mode, you can define the start heating temperature between 32
and 122 °F (0 and 50 °C). The detector stops heating the window when the
temperature is 27 °F (15 °C) above the start temperature.

A.4 Mechanical specifications

Enclosure

Water and dust tight

Electronic modules
Electrical connection

(two entries)

Stainless steel 316 or aluminum, heavy duty, copper-free (less
than 1%), red epoxy enamel finish

• NEMA® 250 type 6p.

• IP66 and IP67 per EN 60529

Conformal coated

• ¾-in. -14 national pipe thread (NPT) conduit or

• M25 x 1.5

Dimensions
Weight

4 x 4.6 x 6.18 in. (101.6 x 117 x 157 mm)
Stainless steel: 6.1 lb. (2.8 kg)

Aluminum: 2.8 lb. (1.3 kg)

A.5 Environmental specifications

The Rosemount 975UR is designed to withstand harsh environmental conditions.

High temperature

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• Designed to meet DNVGL-CG-0339, class D

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• Operating temperature: +167 °F (+75 °C)

• Storage temperature: +185 °F (+85 °C)

Low temperature

Humidity
Enclosure
Water and dust

Vibration

Table A-5: Electromagnetic Compatibility

This product is in conformance with EMC per EN50270.

Radiated immunity EN61000-4-3

Conducted immunity EN61000-4-6

• Designed to meet DNVGL-CG-0339, class D

• Operating temperature: -57 °F (-50 °C)

• Storage temperature: -65 °F (-55 °C)

The Rosemount 975 detector conforms to DNVGL-CG-0339, class B.
The Rosemount 975 detector conforms to DNVGL-CG-0339, class C.

• IP66 per EN60529

• IP68 per EN60529

• Dust: Completely protected against dust.

• Liquids: Protected against immersion between 6 in. (15 cm) and

3 ft. (1 m) in depth. Protected against water jets from all
directions.

The Rosemount 975 detector conforms to DNVGL-CG-0339, class B.

Level per

Electrostatic discharge (ESD) EN61000-4-2

Magnetic field EN61000-4-8

Burst EN61000-4-4

Surge EN61000-4-5

Radiated emission EN550022

Conducted emission EN550022

CAUTION

To fully comply with EMC directive 2014/30/EU and protect against interference caused by
radio frequency interference and electromagnetic interference, shield the cable to the
detector and ground the detector. Ground the shield at the detector end.

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B Wiring instructions

B.1 General instructions for electrical wiring

Follow the instructions detailed in this section for determining the correct wire gauge to
be used for this installation.

1. Use Table B-1 to determine the required wire gauge/size for general wiring, such as
relay wiring. Calculate the permitted voltage drop with respect to load current, wire
gauge, and length of wires.

Table B-1: Maximum DC Resistance at 68 °F (20 °C) for Copper Wire

AWG # mm

20 0.52 - 0.61 1.07 3.50

18 0.81 - 0.96 0.67 2.20

16 1.22 - 1.43 0.43 1.40

2

Ohm per 100 ft. Ohm per 100 m

14 1.94 - 2.28 0.27 0.88

2. Use Table B-2 to select wire gauge for power supply wires. Do not connect any
circuit or load to detectors' supply inputs.

• Select number of detectors connected in one circuit.

• Select wiring length per installation requirements.

• Refer to power supply range for voltage extreme applied.

Table B-2: Wiring Length in Meters (Feet)

Number of
detectors

24 18 16 14 N/A N/A 22-32

20 18 16 14 N/A N/A 22-32

16 20 18 16 14 N/A 22-32

12 20 18 16 14 N/A 20-32

8 20 18 16 14 N/A 20-32

4 and less 20 18 16 16 14 20-32

m (ft) 50 (164) 100 (328) 150 (492) 200 (656) 240 (820)

Recommended wire diameter (AWG) Power supply

Max. length from power supply to last detector

range (Vdc)

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B.1.1 Calculation formula

Use the following formula to calculate minimum wire gauge per wire length between the
power supply (controller) and the detector, considering the number of detectors on the
same power line, where:

L = Actual wire length between the detector and the power supply.
N = Number of detectors per loop
R = Resistance of wire per 100 m (see Table B-2)
V = Voltage drop on the wire
Calculate the voltage drop on the wire as follows:

20 + V = Minimum required voltage of the power supply.

0.2 A is the maximum power consumption of the detector.
For example:
If N = 1 (1 detector in loop), L = 1,000 m, wire size = 1.5 mm2 (see Table B-1, the resistance

per 100 m for 1.5 mm2 is 1.4 Ω).
You calculate the voltage drop in the wire as follows:

The minimum voltage of the power supply should be 20 V + 5.6 V = 25.6 V.

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B.2 Typical wiring configurations

This section describes examples of typical wiring configurations.

Figure B-1: Wiring terminals

A. See table.

B. Alarm relay (C)
C. Ground
D. Alarm relay: normally open (N.O.)

E.

Fault relay (C)

Table B-3: Output Configurations

Output
configuration

1A 975UR-1AXXXXX Fault relay (N.C.) 0-20 mA (sink) 0-20 mA (sink)

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Detector model Terminals

5 8 9

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Table B-3: Output Configurations (continued)

Output
configuration

2A 975UR-2AXXXXX Fault relay (N.C.) Alarm relay (N.C.) 0- 20 mA (source)

3A 975UR-3AXXXXX Fault relay (N.O.) Alarm relay (N.C.) 0 - 20 mA (source)

1R 975UR-1RXXXXX Fault relay (N.C.) Auxiliary relay (N.O.) Auxiliary relay (N.O.)

2R 975UR-2RXXXXX Fault relay (N.O.) Auxiliary relay (N.O.) Auxiliary relay (N.O.)

Detector model Terminals

Figure B-2: Typical Wiring for Four-Wire Controllers (Using Output Configuration 1A
or 2A)

A. Controller

B. First detector
C. Second detector
D. Last detector

E. Power supply

F. Alarm loop

G. End of line (EOL)

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Figure B-3: 0-20 mA Output Configuration 1A (Sink 4-Wire) - Default

A. Detector

B. Controller
C. Input power 18-32 Vdc
D. Return

0-20 mA meter

E.

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Figure B-4: 0-20 mA Output Configuration 1A (Converted to Source Three-Wire)

A. Detector

Controller

B.
C.

Input power 18-32 Vdc
Return

D.

E.

0-20 mA meter

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Figure B-5: 0 - 20 mA Output Configuration 1A (Non-Isolated Sink Three-Wire)

A. Detector

Controller

B.
C.

Input power 18-32 Vdc
Return

D.

E.

0-20 mA meter

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Figure B-6: 0-20 mA Output Configurations 2A and 3A (Source Three-Wire Available
with HART® Protocol)

A. Detector

Controller

B.
C.

Input power 18-32 Vdc
Return

D.

E.

0-20 mA meter

NOTICE

There are no 0-20 mA outputs in output configurations 1R and 2R.

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C RS-485 communication network

By using the RS-485 network capability of the detector and additional software, you can
connect up to 32 detectors in an addressable system with four wires only (two for power
and two for communication). Using repeaters, the number of detectors can be much
larger (32 detectors for each repeater) up to 247 on the same four wires. When using the
RS-485 network, you can read each detector status (Fault, Warning, and Alarm) and to
initiate a built-in test to each detector individually.

For more details, consult Rosemount.

Figure C-1: RS-485 Networking

A. Controller

B. Detector
C. Power supply

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D. RS-485 computer port

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D Accessories

This appendix describes the accessories that can help you maximize fire detection with the
Rosemount 975UR flame detector.

D.1 Flame simulator

Emerson designed the flame simulators specifically for use with Rosemount flame
detectors. The flame simulator includes a halogen lamp that emits UV and IR energy. This
energy is accumulated by a reflector directed towards the detector. This allows the
detectors to be tested under simulated fire conditions without the associated risks of an
open flame.

Figure D-1: Flame Simulator

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D.1.1 Ordering information

The part number of the flame simulator kit is FS-UVIR-975. The kit is supplied in a carry
case that includes:

• Flame simulator

• Charger

• Tool kit

• Reference manual

D.1.2 Unpacking

Verify that you have received the following contents:

• Delivery form

• Flame simulator with integral battery

• Reference manual

• Factory acceptance test forms

• EC declaration

• Storage case

D.1.3 Simulate a flame

WARNING

Hazardous areas

Do not open the flame simulator to charge the batteries or for any other reason in a
hazardous area.

CAUTION

The following test simulates a real fire condition and may activate the extinguishing
system of other alarms.

If you don't want this to happen, disconnect/inhibit other alarms before the test and
reconnect after the simulation.

Procedure

1. Make sure that you are at the correct distance from the detector according to the

type of detector and the detector sensitivity.

2. Aim the detector using the mechanical sight at the center of the detector. Activate

the button and adjust the spot at the center of the detector.

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Figure D-2: Rosemount Rosemount 975UR Detector Target Point

A. Detector target point

3. Keep the simulator aimed at the detector for up to 50 seconds until you receive an

alarm.

D.1.4 Range

Rosemount 975UR 67

4. Wait 20 seconds before repeating the test.

Table D-1: Sensitivity Ranges

Detector sensitivity settings Maximum testing distance

49.2 ft. (15 m) 8 ft. (2.5 m)

1. The minimum distance from the detector is 2.5 ft. (0.75 m).

2. At extreme temperatures, there is a 15 percent maximum reduction in the range.

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NOTICE

Keep the flame simulator in a safe place when not in use.

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D.1.5 Charge the battery

The flame simulator uses lithium ion batteries as a rechargeable power source. When the
batteries are fully charged, the simulator operates for at least 100 times without having to
be recharged. The simulator will not operate when the voltage from the batteries is lower
than the required operational level.

Figure D-3: Flame Simulator Battery Replacement

A. Simulator

B. Battery pack
C. Locking disc
D. Back cover

NOTICE

The item letters in this procedure can be found in Figure D-3.

Procedure

1. Place the flame simulator in a safe area, not exceeding 104 °F (40 °C).

2. Release the locking screw.

3. Unscrew the battery back cover (D) counter-clockwise.

Unscrew the locking disc (C) clockwise.

4.

5. Pull out the battery from the flame simulator.

6. Connect the battery to the charger.

7. Charge for a maximum of two to three hours.

8. Disconnect the charger.

9. Insert the battery in the flame simulator.

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10. Screw on the locking disc (C).

11. Screw on the back cover (D).

12. Lock the back cover with the locking screw.

D.1.6 Replace the battery

NOTICE

The item letters shown in this procedure can be found in Figure D-3.

Procedure

1. Place the flame simulator on a table in a safe area, not exceeding 104 °F (40 °C).

2. Release the locking screw.

3. Unscrew the battery back cover (D) counter-clockwise.

4.

Unscrew the locking disk (C) clockwise.

5. Pull out the battery from the flame simulator.

6. Insert the new battery pack in the simulator housing.

Use only Rosemount battery pack, PN 00975-9000-0012.

7. Screw on the locking disc (C).

8. Screw on the back cover (D).

9. Lock the back cover with the locking screw.

NOTICE

For more information, refer to the Rosemount FS-UVIR-975 Flame Simulator

Manual (00809-0800-4975).

D.1.7 Technical specifications

Table D-2: Flame Simulator Technical Specifications

General • Temperature range: -4 to +122 °F (-20 to +50 °C)

• Vibration protection: 1 g (10 - 50 Hz)

Electrical • Rechargeable four cell lithium-ion battery:

— Power: 14.8 V (4 x 3.7 V), maximum current: 0.2 A

— Charging: 16.8 V (4 x 4.2 V), maximum current: 4 A

• Battery capacity: 2.6 Ah

• Charging time: Two hours at 2 A

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Table D-2: Flame Simulator Technical Specifications (continued)

Physical • Dimensions: 9 x 7.3 x 5.35 in. (230 x 185 x 136 mm)

• Weight: 5.5 lb. (2.5 kg)

• Enclosure: aluminum, heavy duty copper free, black zinc

coating

• Explosion-proof enclosure

ATEX and IECEx
Ex II 2 G D
Ex db ib op is IIB +H2 T4 Gb
Ex ib op is tb IIIC T135 °C Db

-4 to +122 °F (-20 to +50 °C)

• Water and dust tight: IP65

Electromagnetic interference
(EMI) compatibility

Table D-3: Immunity Tests

Title Basic standard Level to be tested

Electrostatic discharge (ESD) IEC 61000-4-2 6 kv / 8 kv contact / air

Radiated electromagnetic field IEC 61000-4-3 20 V/m (80 MHz to 1 GHz)

Conducted disturbances IEC 61000-4-6 10 Vrms (150 kHz to 80 MHz)

Immunity to mains supply
voltage variations

Table D-4: Emission Tests

Title Basic standard Level to be tested Class

Radiated emission IEC 61000-6-3 40 dbuv/m (30 MHz to

See Table D-3 and Table D-4.

MIL-STD-1275B N/A

10 V/m (1.4 GHz to 2 GHz)
3 V/m (2.0 GHz to 2.7 GHz)

230 MHz)
47 dbuv/m (230 MHz
to 1 GHZ)

Like Class B of
EN55022

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D.2 Tilt mount: PN 00975-9000-0001

The tilt mount provides accurate directional selection for optimum area coverage.

Figure D-4: Tilt Mount

D.3 Duct mount

The duct mount limits the cone of vision of the installed detector to 70 degrees horizontal
and vertical.

For more instructions, refer to the Duct Mount Manual (00809-0600-4975).

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D.4 Weather cover: PN 00975-9000-0003

The weather cover protects the detector from different weather conditions, such as snow
and rain.

Figure D-5: Weather Cover

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D.5 Air shield: PN 00975-9000-0005

The air shield is suitable for use with the Rosemount 975 series flame detectors for both
the aluminum and stainless steel enclosures.

Optical flame detectors are often used in highly polluted or dirty areas that force
maintenance personnel to access the detector frequently to clean its optical window. The
special air shield, developed for the Rosemount 975 series optical flame detectors, allows
operators to install the flame detectors under tough environmental conditions where they
may be exposed to oil vapors, sand, dust, and other particulate matter.

The temperature of the air supply to the air shield should not exceed 140 °F (60 °C) at any
time.

Air pressure source: clean, dry, and oil-free air
Inlet pressure: 30-45 psi (2-3 bar), maximum 100 psi (7 bar)
Cubic feet per minute: 1.5-2.8
Tube outside diameter: ¼-in. national pipe thread (NPT)/6 mm
Connecting adapter size: 7/16-in. NPT
Operation temperature: -67 to 185 °F (-55 to 85 °C)
For more instructions, refer to the Rosemount 975 Air Shield Manual (00809-0700-4975).

Figure D-6: Rosemount 975 Air Shield

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E SIL-2 features

This appendix details the special conditions to comply with the requirements of EN 61508
for SIL 2.

The Rosemount 975UR Flame Detector can only be used in low or high demand mode
applications; see IEC 61508.4, Chapter 3.5.12.

E.1 Safety relevant parameters

Perform the following functional checks of the detector every thirty days.

• HFT: 0

• PFD: 1.9 x 10-4 (≈ 2% of SIL-2) if only alarm relay is used for alerting.

• PFD: 1.9 x 10-4 (≈ 2% of SIL-2) if 0-20 mA - interface is used as alarm.

• SFF: 97% fulfills the conditions of EN 61508 for SIL2.

E.2 Guidelines for configuring, installing,

operating, and service

The alert conditions according to SIL-2 can be implemented by an:

• Alert signal via 20 mA current loop

or

• Alert signal via alarm relay and the fault relay

E.2.1 Conditions for safe operating

1. The flame detector shall consist only of the approved hardware and software
modules.

2. The 24 V power supply must fulfill the requirements for PELV/SELV of EN 60950.

3. The automatic built-in test (BIT) must be activated.

4. The setup parameters must be verified (as described in

for alerting and Using the alarm relay contact for alerting), and the function of the

Rosemount 975 flame detector (flame detection, function of the 0-20 mA interface,
relay functions) must be checked completely.

5. The function of the Rosemount 975UR Flame Detector (flame detector, function of
the 0-20 mA interface, and relay functions) must be checked completely.

Using the 0-20 mA interface

E.2.2 Using the 0-20 mA interface for alerting

The following parameters shall be set:

• Automatic built-in test: On

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• Connected to 0-20 mA terminals

The following allowed output current must be supervised with an accuracy of ±5 percent.

• Normal state: 4 mA

• Warning state: 16 mA

• Alarm state: 20 mA

The output current must be supervised regarding the over-and under run of the 0-20 mA.

E.2.3 Using the alarm relay contact for alerting

The following parameters shall be set:

• Automatic built-in-test: On

• Connected to normally closed (N.C.) contact of alarm relay terminals

• Connected to fault relay terminals

The relay contacts (alarm and faulty relay) must be protected with a fuse rated at 0.6 of
the nominal specified relay contact current.

The maximum contact rating that is allowed per SIL-2 is 30 Vdc.
The contact of the alarm relay opens if there is a fire alarm.
During the forwarding and evaluation of the alarm, the relay contact opens.

E.2.4 Other

1. The complete function of the flame detector (flame detection, function of the
0-20 mA interface, and the relays) must be examined at least every six or twelve
months (see Safety relevant parameters) when the flame detector must be
switched OFF and ON.

2. The window of the sensor must be examined at appropriate time intervals for
partial contamination.

3. The HART® and the RS-485 interfaces must not be used for the transmission of the
safety-related data.

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F End of line resistor

The Rosemount 975 series can be equipped with an EOL resistor inside the flameproof 'd'
terminal compartment.

The EOL resistor can be situated in the rear part, which is Ex e or Ex d, depending on the
application. When the resistor is assembled, the rear part can be used as Ex d only.

To meet the allowed power consumption, the total resistance should be higher than

1.5 KΩ.

Figure F-1: Rosemount 975UR Flame Detector

A. Terminal number 5

B. Terminal number 6
C. Rosemount 975UR flame detector
D. End of line resistor

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For more information:

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