Ametek LAND RT8A User manual

Thermometer
Copyright © 2005 - 2012 Land Instruments International
User Guide
Issue 3: January 2012
Part Nº is 801450
Publication Nº PP309
Language: English
RT8A

Health and Safety Information
Read all of the instructions in this booklet - including all the WARNINGS and CAUTIONS
- before using this product. If there is any instruction which you do not understand.
DO NOT USE THE PRODUCT.
Safety Signs
WARNING
Indicates a potentially hazardous situation which, if not avoided, could result in death or
personal injury.
CAUTION
Indicates a potentially hazardous situation which, if not avoided, could result in minor or
moderate injury to the user or users, or result in damage to the product or to property.
NOTE
Indicates a potentially hazardous situation which, if not avoided, could result in damage or the loss of
data.
Equipment Operation
Use of this instrument in a manner not specied by Land Instruments International may be hazardous.
Read and understand the user documentation supplied before installing and operating the equipment.
Protective Clothing, Face and Eye Protection
It is possible that this equipment is to be installed on, or near to, machinery or equipment operating at
high temperatures and high pressures. Suitable protective clothing, along with face and eye protection
must be worn. Refer to the health and safety guidelines for the machinery/equipment before installing
this product. If in doubt, contact Land Instruments International.
Electrical Power Supply
Before working on the electrical connections, all of the electrical power lines to the equipment must
be isolated. All the electrical cables and signal cables must be connected exactly as indicated in these
operating instructions. If in doubt, contact Land Instruments International.
Storage
The instrument should be stored in its packaging, in a dry sheltered area.
Unpacking
Check all packages for external signs of damage. Check the contents against the packing note.
Lifting Instructions
Where items are too heavy to be lifted manually, use suitably rated lifting equipment. Refer to the
Technical Specication for weights. All lifting should be done as stated in local regulations.
IMPORTANT INFORMATION - PLEASE READ

Contact Us
UK - Droneld
Land Instruments International
Tel: [phone]
E-Mail: [email protected].uk
Web: www.landinst.com
USA - Pittsburgh
AMETEK Land, Inc.
Tel: [phone]
E-Mail: [email protected]
Web: www.ametek-land.com
For further details on all LAND/Ametek ofces, distributors and representatives, please visit
our websites.
Return of Damaged Goods
IMPORTANT If any item has been damaged in transit, this should be reported to the carrier and to the
supplier immediately. Damage caused in transit is the responsibility of the carrier not the supplier.
DO NOT RETURN a damaged instrument to the sender as the carrier will not then consider a claim. Save
the packing with the damaged article for inspection by the carrier.
Return of Goods for Repair
If you need to return goods for repair please contact our Customer Service Department. They will be
able to advise you on the correct returns procedure.
Any item returned to Land Instruments International should be adequately packaged to prevent damage
during transit.
You must include a written report of the problem together with your own name and contact information,
address, telephone number, email address etc.
Design and Manufacturing Standards
The Quality Management System of Land Instruments International is approved to BS EN ISO 9001 for
the design, manufacture and on-site servicing of combustion, environmental monitoring and non-contact
temperature measuring instrumentation.
Approvals apply in the USA
This instrument complies with current European directives relating to Electromagnetic
Compatibility 89/336/EEC and Low Voltage Directive 73/23/EEC.
Operation of radio transmitters, telephones or other electrical/electronic devices in close proximity
to the equipment while the enclosure doors of the instrument or its peripherals are open, may cause
interference and possible failure where the radiated emissions exceed the EMC directive.
The protection provided by both CE and IP classications to this product may be invalidated if alterations
or additions are made to the structural, electrical, mechanical or pneumatic parts of this system. Such
changes may also invalidate the standard terms of warranty.
Copyright
This manual is provided as an aid to owners of Land Instruments International’s products and contains
information proprietary to Land Instruments International. This manual may not, in whole or part, be
copied, or reproduced without the expressed written consent of Land Instruments International Ltd.
Copyright © 2012 Land Instruments International.

Thermometer User Guide
RT8A
Technical support
Technical support for the LAND RT8A Thermometer can be obtained by either
contacting the address/telephone number on the cover of this User Guide or
by e-mail at the following address:
 [email protected]

User Guide Thermometer
RT8A
Contents
1 Introduction 1
1.1 General Introduction 1
1.2 About the RT8A thermometer 1
2 Instrument Specications 2
2.1 Specication Table 2
2.2 Thermometer Dimensions 3
2.3 Target Spot Size 3
2.4 Thermometer Installation 4
3 Electrical Connections 5
3.1 General Connections 5
3.2 Loop Resistance 6
4 Thermometer Operation 7
4.1 General 7
4.2 Location of Controls 7
4.3 Adjusting the ‘Emissivity’ Setting 8
4.4 Adjusting the Averager ‘Response Speed’ Setting 9
4.5 Settings Archive 9
5 Mountings and Accessories 10
5.1 General 10
5.2 Services 12
6 Maintenance 13
6.1 General 13
7 Emissivity 14
7.1 Refractories 14
7.2 Alloys 15
7.3 Metals 16
7.4 Miscellaneous 17

Thermometer User Guide
RT8A

Page 1
User Guide Thermometer
RT8A
1 Introduction
1.1 General Introduction
This publication provides the necessary information required to safely operate
the Land RT8A Thermometer.
It is important to fully check all equipment with which you have been
supplied.
The equipment must only be used, maintained and serviced by suitably
trained personnel, capable of carefully following the procedures and guidelines
given in this User Guide.
This User Guide should be read thoroughly before proceeding with any
operations detailed within it and it is advisable that it is kept readily available,
for reference when the equipment is in general use.
1.2 About the RT8A thermometer
The Land RT8A Thermometer is a highly accurate, non-contact infrared
thermometer, designed for independent or ‘stand alone’ applications.
The thermometer features include:
• stand alone operation
• adjustable response speed
• 4 to 20mA loop powered output, linear over the temperature span of
the instrument
• built-in emissivity controls
Fig. 1 Land RT8A thermometer 309001

Page 2
Thermometer User Guide
RT8A
Operating Temperature Range:
(focused at innity)
RT80A
RT81A
RT82A
RT83A
0 to 250°C
0 to 500°F
0 to 500°C
0 to 1000°F
Specied Temperature Range: RT80A
RT81A
RT82A
RT83A
0 to 250°C
30 to 500°F
0 to 500°C
30 to 1000°F
Output: Linear 4 to 20mA over temperature range
Field of view: See section 2.2
Emissivity: 0.10 to 1.00 (adjustable in 0.01 increments)
Waveband: 8 to 14μm (nominal)
Response time(3t): 1 to 10s (adjustable)
Resolution: <0.2°C
Accuracy (absolute): <½° of span
(within specied temperature range)
Ambient temperature limits: -5 to 50°C/23 to 122°F (specied)
-5 to 70°C/23 to 158°F (storage)
Drift with ambient temperature: <1.5° per 10° change in ambient temperature
Drift with time: <1°C (2°F) per year
Power supply voltage limits: 11 to 45V d.c. (26V d.c. nominal)
Maximum load resistance: 1KΩ
EMC: EN 50 082-2 (immunity)
EN 50 081-1 (emission)
IEC 61010 (electrical safety)
Sealing: Designed to meet IP65/NEMA4 requirements
Vibration: 3g any axis (10 to 300Hz)
Weight: 0.5kg/1.1lb
2 Instrument Specifications
2.1 Specification Table

Page 3
User Guide Thermometer
RT8A
2.2 Thermometer Dimensions
Fig. 2 - Land RT8A thermometer dimensions 309002
2.3 Target Spot Size
Fig. 3 - Land RT8A thermometer target spot size table 309003
114/4.49
80.5/3.17 158/6.22
Mounting pad: 2 holes, 1/4in BSW,
7/0.3 deep on 25/0.98 centres
All dimensions in mm/in
Not to scale
0.83 1.02 1.34 2.13 3.39 4.80 6.14
Minimum Target Size (mm)
Distance to Target (mm)
Minimum Target Size (in)
Distance to Target (in)
0 300 500 1000 1500 2000 2500
21 26 34 54 86 122 156
0 11.8 19.7 39.4 59.1 78.7 98.4

Page 4
Thermometer User Guide
RT8A
The Land RT8A thermometer operates by sensing radiation from within a well
dened ‘eld of view’. The intersection of this eld of view with the intended
target, determines the ‘target spot’, the area where the temperature is
measured. Fig. 3 shows the RT8A thermometer target spot size table.
2.4 Thermometer Installation
The location of the RT8A thermometer should be carefully chosen, such that
it is easily accessible and in a position not unnecessarily exposed to heat,
fumes or liquid spray. The sight path between the thermometer and the
target, should be as free as possible from smoke, liquid spray and from the
intrusion of machinery. The axis of the thermometer should be at right angles
to the target surface, however, an angle of up to 45° from the normal is
acceptable. It is also important that the intended target completely lls the
thermometer eld of view at the selected installed distance and that no part
of the sight path is obstructed.
When choosing a suitable location for mounting the RT8A thermometer, the
following criteria should be considered:
• If the installation area is not clean or free from dust, smoke or water
spray, then a Land air purge system must be utilised to ensure that the
thermometer lens is kept free from such airborne contaminants. Ensure that a
suitably conditioned air supply is available.
• If the surrounding ambient temperatures of the installation area are
outside the thermometer specication, then a Land water cooled protective
jacket must be utilised to ensure that the thermometer operates at the
specied ambient temperature. Ensure that a suitably conditioned water
supply is available.
NOTE
In some RT8A applications, a sighting tube may be required to
eliminate any unwanted reections from entering the thermometer
and to keep the sight path clear from obstructions. Sighting tubes can
also be used to create a ‘stand-off’, between the thermometer and the
process under observation.
When selecting a suitable sighting tube, it is important to ensure that
the internal bore of the tube is at least 25% greater than the largest
target spot size over the tubes length. All distances must be measured
from the thermometer datum, which is located at the front of the
thermometer.

Page 5
User Guide Thermometer
RT8A
3.1 General Connections
The electrical connections for the RT8A thermometer power supply and
temperature output are made via the 6-way socket on the rear of the
thermometer (see Fig. 6).
The connection to the thermometer can be made via any of the following:
• Pre-wired 4m cable (Land Part No. 029.673)
• 6-way plug (Land Part No. 206.551)
• 6-way plug housed in protective jacket end cap (Land Part No. 091.562)
3 Electrical Connections
To connect the 6-way plug to the RT8A thermometer (see Fig. 4):
• Align the red marker near the lugs of the plug, with the red marker
located above the keyway in the thermometer socket.
• Push the plug into the socket, ensuring that the locking sleeve slides
forwards, locking the plug to the socket.
To disconnect the 6-way plug to the RT8A thermometer:
• Grip the locking sleeve portion of the plug.
• Slide the locking sleeve rearwards to release the locking mechanism and
disconnect the plug from the thermometer socket.
Thermometer
Pin Function Cable Colour End Cap Pin No.
1 - - -
2 - - -
3 V+, 4 to 20mA Red 5
4 - - -
5 - - -
6 V-, 4 to 20mA Black 6

Page 6
Thermometer User Guide
RT8A
Locking Sleeve
Lugs Keyway
Red Markers
Fig. 4 - Connecting the 6-way plug to the RT8A Thermometer 309004
3.2 Loop Resistance
The maximum allowable loop resistance in the RT8A thermometer current
loop, for a given power supply voltage, is illustrated in Fig. 5.
NOTE
The system load resistance includes the cable resistance and the indicator
resistance.
Fig. 5 - Graph showing load resistance versus power supply voltage 309005
0 5 10 15 20 25 30 35
1000
900
800
700
600
500
400
300
200
100
0
Power Supply Voltage (V)
Maximum Loop Resistance (ohms)

Page 7
User Guide Thermometer
RT8A
4 Thermometer Operation
4.1 General
It is recommended that the ‘Emissivity’ and ‘Response Speed’ controls are
set to match the requirements of the specic application and measurement
location, before installation. This is particularly relevant if the thermometer
is to be used in a location which is difcult to access and/or is used in
conjunction with a protective jacket and back cap.
4.2 Location of Controls
The ‘Emissivity’ and ‘Response Speed’ control switches are located on the rear
face of the thermometer. The controls are protected by a screw-on cap
(see Fig. 6).
NOTE
To ensure that the electronics of the thermometer are fully sealed
against the ingress of moisture and dirt, the screw-on cap covering the
thermometer controls must be replaced immediately after making any
settings or adjustments.
Fig. 6 - Location of RT8A thermometer controls screw-on cap 309006
Screw-on cap covering
thermometer controls
Rear face of RT8A
thermometer
Electrical connector
Not to scale

Page 8
Thermometer User Guide
RT8A
4.3 Adjusting the ‘Emissivity’ Setting
To ensure that the Land RT8A thermometer makes consistent accurate
temperature measurements, an emissivity correction value must be set in the
thermometer which accurately corresponds with the target under observation.
The emissivity value can be set in the range 0.10 to 1.00 in adjustable
increments of 0.01. The thermometer is supplied with the emissivity value
pre-set to 1.00.
To set the emissivity value:
• Remove the screw-on cap covering the control switches.
• Set the emissivity value using the ‘SW1’ and ‘SW2’ switches (see Fig. 7).
Switch ‘SW1’ denotes the rst gure after the decimal point of the
emissivity value.
Switch ‘SW2’ denotes the second gure after the decimal point of the
emissivity value.
e.g. for an emissivity value of ‘0.87’, ‘SW1’ should be set to ‘8’ and ‘SW2’
should be set to ‘7’.
When switch ‘SW1’ is set to ‘0’, this denotes a ‘1’ before and a ‘0’ after the
decimal point of the emissivity value.
e.g. for an emissivity value of 1.00, ‘SW1’ should be set to ‘0’ and ‘SW2’
should be set to ‘0’.
• Ret the screw-on cap covering the control switches.
Fig. 7 - RT8A Thermometer ‘Emissivity’ an ‘Response Speed’ Contro 309007
Emissivity
Example = 0.85
Response Speed
Fully anti-clockwise = 1sec (3t)
Fully clockwise = 10sec (3t)
SW2
SW1
P1
Example settings
Emissivity SW1 SW2
0.10 1 0
0.80 8 0
0.85 8 5
0.92 9 2
1.00 0 0
e=0.85

Page 9
User Guide Thermometer
RT8A
4.4 Adjusting the Averager ‘Response Speed’ Setting
The response speed setting allows the time constant of the Land RT8A
thermometer to be adjusted to suit the application. The response speed
relates to the signal output rate and gives an average reading over the
duration of the response speed time value and can be set via potentiometer
P1 (see Fig. 7).
The averager response speed can be set to any value between 1 and 10
seconds (for 0 to 95% of the nal reading).
To increase the response speed value (i.e. make the response faster):
• Remove the screw-on cap covering the control switches.
• Turn the potentiometer ‘P1’ anti-clockwise. When ‘P1’ is turned fully
anti-clockwise, the response speed is 1 second (3t)
To decrease the response speed value (i.e. make the response slower):
• Remove the screw-on cap covering the control switches.
• Turn the potentiometer ‘P1’ clockwise. When ‘P1’ is turned fully
clockwise, the response speed is 10 seconds (3t).
• Ret the screw-on cap covering the control switches.
4.5 Settings Archive
It is recommended that any emissivity or response speed settings made,
are recorded and saved to archive. This allows future reference and quick
traceability of settings without having to access the instrument to check
switch settings. When values for emissivity and response speed are set, enter
the information and values in the table below:
Serial Number Date Emissivity Response Speed

Page 10
Thermometer User Guide
RT8A
5 Mountings and Accessories
5.1 General
A comprehensive range of mountings and accessories is available for the
RT8A thermometer, ensuring it is environmentally protected when utilised in
hostile or challenging applications.
NOTE
If the thermometer is to be used in an area of ambient temperature
higher than that specied, then the thermometer must be housed in a
protective cooling jacket. If the thermometer is to be used in an area
where the atmosphere contains a high proportion of dust/smoke/steam
etc, then the thermometer must be used in conjunction with an air purge
system, to keep the thermometer lens clean and free from contamination.
Sighting tube
mounting ange
Electrical
Connections
Position of RT8A thermometer
within protective jacket assembly
End cap
assembly
Cooling jacket
assembly
Air/water
cooling
Air purge
assembly
Fig. 8 - Location of RT8A thermometer in protective jacket assembly 309008
Not to scale

Page 11
User Guide Thermometer
RT8A
Fig. 9 - RT8A thermometer protective assembly dimensions 309009
3x equi-spaced mounting
holes 6.5 to 7.0/0.26 to 0.28
clearance for M6 bolts
Thermometer removal clearance
Approx. 200/8.0
150/5.9 170/6.7 110/4.4
430/17.0
117/4.6
All dimensions in mm/in Not to scale
120/4.7
SideView
TopView

Page 12
Thermometer User Guide
RT8A
5.2 Services
When any cooling or purging accessories are utilised, it is important that the
air and water supply to these facilities are fully conditioned and supplied at
the recommended ow rates. The following information details the specied
ow rates:
S4-J Cooling Jacket Assembly
Requirement: Conditioned water supply (clean and free from any
contaminants) Flow rate: 1ltr/min or 0.035cu.ft/min
S4-P Air Purge Assembly
Requirement: Conditioned air supply (clean and dry, free from any
contaminants) Flow rate: 1ltr/sec or 2cu.ft/min
CAUTION
“Over-cooling” of the thermometer may cause a build-up of condensation
on or inside the instrument.
To prevent this, ensure that the water supply temperature is not lower
than the local dewpoint temperature.

Page 13
User Guide Thermometer
RT8A
6 Maintenance
6.1 General
RT8A thermometer maintenance consists mainly of ensuring that the
thermometer lens is kept clean and free from contaminants and that all
services to the system (water and air supplies) are set correctly and are
routinely checked.
It is recommended that routine checks of the RT8A thermometer system, are
incorporated into any local maintenance schedules.

Page 14
Thermometer User Guide
RT8A
7 Emissivity
In order to obtain accurate temperature measurements, the emissivity value
of the target surface must be known. This section of the RT8A Thermometer
User Guide contains typical emissivity values of the most commonly measured
materials. Where no emissivity value is quoted, this means that either
the thermometer is not suitable for the measurement application or the
temperature of the target is outside the thermometer’s measurement span. If
you have a query regarding the emissivity of the target in your measurement
application, contact Land Instruments International for assistance.
7.1 Refractories
Refractories
Material Emissivity Value
Magnesite
oxidised
0.60
0.85
Brick
Red 0.90
White
Refractory 0.80
Silica 0.80
Sillimanite 0.60
Ceramics 0.90
Alumina 0.60
Fig. 10 - Typical Emissivity Values for Refractories 309010