Scott Instruments 4688IR Series Manual instruction

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Rev: 4688IR (G)
Date: 10/30/03
CN: 3209
Part #087-0007G
IR
Series 4688IR/4679IRSeries 4688IR/4679IR
Series 4688IR/4679IRSeries 4688IR/4679IR
Series 4688IR/4679IR
Operation & Maintenance Manual
THREE KEY POINTS TO OPERATIONAL SAFETY
To assure both personnel and facility safety, it is extremely
important to observe all transmitter installation and operational
safety requirements. The three key points listed below may be
found in the contents of this manual.
#1 - Install the system correctly following all local, state, and
federal guidelines.
#2 - Perform regular operational tests on the transmitter. This
helps ensure the unit is functioning properly.
#3 - Maintain a zero adjustment log for each transmitter and
adhere to the schedule. Infrared combustible gas transmitters
require periodic zero adjustment in order to continue to operate
accurately. Failure to properly operate and maintain this
instrument could result in serious injury.
! SAFETY FIRST !
®
SERIES 4600-IR
ESC
IR
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1
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Transmitter Quick Start
1. Mount and wire the transmitter (See "Transmitter Installation").
2. Apply power to the transmitter. All segments and indicators on the
display will turn on for 2 seconds, then will turn off for 2 seconds. The
transmitter will subsequently enter a 30 second warm-up period
(countdown shown on the display).
3. Select the gas to be detected.
a. Touch the magnet to the up arrow key and observe
"USER" on the display.
b. Touch the magnet to the E key and observe
"A1.SP" is the first parameter to be displayed.
c. Repeatedly touch (or hold to scroll) the magnet to
the UP key until the display shows "SR.GN." Touch
the E key.
d. The display should read "1". Use the Up or Down arrow keys to
change the number to the appropriate gas as shown in the following
table below. See Appendix 3 for gas cross-sensitivity tables.
e. When the display has the correct gas, touch the magnet to the E
key and observe the display read "SEt". Then, touch the magnet to the
Z key 3 times until the display shows "RUN."
The instrument is now ready to operate! Consult the manual
for more information on the instrument's many features.
Parameter SR.GN = Gas Notes
Standard
Gas Set
1
2
3
4
5
6
10
Methane
Ethane
Propane
Butane
Pentane
Hexane
Propylene
Extended
Gas Set
9
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Ethylene
Acetone
IPA
MEK
Toluene
Methanol
Butadiene
Pure Methane
20% Hexane
Ethanol
Benzene
Xylene
Isobutanol
Rotosolv-1
Cyclohexane (0-60% LEL)
Only ONE
"extended" gas
can be selected
on tran s m itte rs
ordered with
th is o pti o n.
Other standard
gases are still
selectable.
Model
4679IR CO2
Gas
Detector
ONLY
64 Carbon Dioxide
Hydrocarbon
settings are
not available
AL1 AL2 FAULT
INHIBIT MAINT
AL1 AL2 FAULT
INHIBIT MAINT
ESC
IR
SERIES 4600-IR
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2
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
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3
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Contents
Start-Up, General Information, & Installation _________ 5
Introduction _____________________________________________ 6
Principle of Operation _____________________________________ 6
Other Gas Sensitivities - Model 4688-IR ONLY __________________ 6
Lower Explosive Limit - Model 4688-IR ONLY ___________________ 7
Suitability For Use in Hazardous Locations _____________________ 7
Using a Flowcell _________________________________________ 7
General Instrument Overview Map _________________________ 8
Transmitter Installation _____________________________________ 9
Installation Considerations _________________________________ 9
Using the Rain Shields and Filters __________________________ 10
Wiring and Power _______________________________________ 12
Mounting the Transmitter __________________________________ 13
Powering The Transmitter _________________________________ 15
Installation Drawings _____________________________________ 16
Transmitter Operation ________________________________ 21
Basic Instrument Adjustments ______________________________ 22
Navigating the Instrument _________________________________ 22
RUN Mode _____________________________________________ 22
How to Adjust Transmitter Parameters _______________________ 22
Adjusting LCD Display Contrast ____________________________ 23
Acknowledging Latched Alarms ____________________________ 24
Inhibiting Output ________________________________________ 24
Zeroing the Transmitter ___________________________________ 24
Adjusting the Loop Output Parameters _______________________ 26
Setting Alarm and Sensor Parameters ___________________ 27
Relay N.O./N.C. Status ___________________________________ 27
Optional Alarm Relays ____________________________________ 28
Sensor Parameters______________________________________ 30
Report Generation______________________________________ 30
Setting Transmitter Security________________________________ 31
The LOCK Menu ________________________________________ 31
Toggling Parameter Security On/Off (LK.ON) __________________ 32
Changing the Password (LK.PW) ___________________________ 32
Auto-Lock Timer (LK.tM) __________________________________ 32
Instrument Parameter Change Example ___________________ 33
Serial Communications ________________________________ 35
Setting Up for Digital Communications ___________________ 36
Using MODBUS®Serial Communications _________________ 38
Configuring the Master Device and Tagging Data Elements _______ 38
Registers, Coils, and Addresses ____________________________ 39
Accessing Parameter Data - The ABCs of Reading and Writing ___ 40
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4
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Writing a Parameter to Memory ___________________________ 41
Instrument Navigation & Parameter Reference_______ 43
Parameter Navigation Map ________________________________ 44
The USER Menu _____________________________________________ 45
Alarm Relay Parameters __________________________________ 45
Sensor Parameters______________________________________ 46
The LOCK Menu ____________________________________________ 49
The COMM Menu ___________________________________________ 50
Loop Current Parameters _________________________________ 50
Report Generator Parameters _____________________________ 50
Serial Communication Parameters __________________________ 52
The FACT Menu ________________________________________ 54
Maintenance, Troubleshooting, & Product Support ____ 55
Maintenance ________________________________________________ 56
Routine Maintenance_____________________________________ 56
Periodic Maintenance ____________________________________ 57
Troubleshooting ____________________________________________ 62
General Difficulties ______________________________________ 62
Fault Codes ____________________________________________ 63
Resetting Factory Defaults _________________________________ 66
Contacting Scott Instruments _______________________________ 66
Technical Specifications _____________________________________ 67
Appendix 1 - MODBUS®Registers & Coil Addressing ______ 68
Addresses _____________________________________________ 68
MODBUS®Read-Only Register Descriptions __________________ 69
Appendix 2 - (FSR) Command Functions ___________________ 71
Appendix 3 - Instrument Cross-Sensitivity _________________ 74
Record Your Parameters!___________________________________ 76
Spare Parts & Accessories __________________________________ 77
Scott Instruments Warranty ________________________________ 78
Statement of Year 2000 Compliance ___________________________ 78
Index________________________________________________________ 79
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5
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Start-Up, General
Information, &
Installation
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6
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Introduction
The GasPlus-IR 24VDC powered INFRA-RED GAS TRANSMITTER uses
infrared absorption technology to monitor the level of combustible
hydrocarbon gases (Model 4688-IR) or CO2(Model 4679-IR) in the
surrounding atmosphere and transmits an analog (4-20 mA) or digital
(Modbus®) signal that is proportional to the measured concentration. The
output signal is linear for the specific gas being measured. Linearization
curves for numerous gases are built into the instrument and are user
selectable.
The instrument features 2 alarm relays capable of indicating high and high-
high alarm conditions, and a separate relay for indicating faults (relays are
optional). A local display reports concentration readings in units of either
%LEL or %V/V (user selectable), as well as system status. The operator
panel interface uses a Scott Instruments magnetic screwdriver for accessing
the system parameters and may be password protected. Non-intrusive user
setup and calibration permits operation and maintenance from within
classified areas.
Principle of Operation
Infrared radiation propagating from an incandescent emitter passes through a
volume of gas, then is reflected by a mirror onto 2 fixed detectors. One
detector is tuned to a wavelength that is absorbed by hydrocarbons or CO2,
while the other detector is tuned to a nearby wavelength that is not absorbed.
The ratio of the output voltages of the 2 detectors is used to compute the
concentration of gas. As gas concentration increases, the incremental output
produced by the detectors decreases. The instrument then uses a gas-
specific algorithm to linearize the signal. Since the amount of infrared
absorption differs with each gas, the instrument's cross-sensitivity will vary.
For example, an instrument setup to detect methane, which absorbs less
infrared radiation than most other hydrocarbons, will produce high readings
when exposed to most other combustible gases.
Other Gas Sensitivities - Model 4688-IR
ONLY
The Model 4688-IR is specifically tuned to detect certain hydrocarbon gases
and will not detect non-hydrocarbon combustibles such as NH3, H2, etc. Scott
Instruments' Model 4600 GasPlus Universal Toxic Gas Transmitter provides
an excellent solution for many of these gases. Hydrocarbons not listed as
available (see parameter SR.GN) may or may not be detectable by the
transmitter. Consult the factory for further information.
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7
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Lower Explosive Limit - Model 4688-IR ONLY
Combustible gas mixtures can be ignited only between certain concentration
limits. These limits are known as the Lower Explosive Limit (LEL) and the
Upper Explosive Limit (UEL). When these terms are used, it is assumed that
a normal atmospheric air background (20.9% O2) is present. For example,
the LEL for methane is a concentration of 5.00 %V/V (volume per volume) in
air.
Combustible gas sensors are designed to operate at concentrations under
the LEL, and typically the readings are calibrated in %LEL. For methane, 100
%LEL is defined as a concentration of 5.00% in air; 50% LEL is defined as a
concentration of 2.5%, and so on. If the reading is under 100% LEL, the gas
at the sensor cannot ignite. However, even very low readings indicate that
there may be a significant gas leak at some distance from the sensor.
Readings exceeding 100% LEL are possible.
Suitability For Use in Hazardous Locations
The Models 4688-IR and 4679-IR are designed to be acceptable for use in
Class 1, Zones 1 and 2, Groups B, C, and D hazardous (classified) locations
(these locations are approximately equivalent to Class 1, Division 1 and 2,
Groups B, C, and D, as defined in the pre-1996 NEC). The instrument
accomplishes this primarily through the use of the explosion-proof method of
protection (Ex d). The 1 exception is the heater which uses the intrinsically-
safe (Ex ib) method of protection.
Using a Flowcell
When using the GasPlus-IR with a flowcell, it is important to recognize that
output will vary with gas pressure. The Ideal Gas Law establishes a
relationship between pressure and the number of molecules. Where
P=pressure, V=volume, n=number of molecules, R=gas constant, and
T=temperature): P V = nRP V = nR
P V = nRP V = nR
P V = nRTT
TT
T
If temperature is held at a constant, the number of molecules in a given
volume of gas (gas density) will vary linearly with pressure. Since the amount
of infrared absorption increases with gas density, the higher the pressure in
the flowcell with respect to atmospheric, the higher the instrument's
concentration output will be (and vice-versa). Note that the flowcell pressure
can be either positive (i.e., gas is being pushed into the flowcell) or negative
(i.e., gas is being pulled through the flowcell).
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8
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
General Instrument
Overview Map
Alphanumeric Display - Used for
displaying decimal values in the range -999
to -0.00 and 0.000 to 9999, hexadecimal
values in the range 0000 to FFFF, and text
labels representing parameters during user
setup.
Gas Concentration Units - Parameters can
be set to display gas concentration in %LEL
or in %V/V.
Security Indicator (Lock) - Appears when
software security is active, prohibiting
parameter editing. When the security
parameter is "locked" parameters may be
reviewed, but not changed.
Alarm Indicators - Visible when alarm,
fault, inhibit, or maintenance conditions
exist.
Case Fitting - Stainless steel housing
containing emitter, detectors, and heater I.S.
barrier.
Replacement Emitter Assembly - Provides
infrared radiation for detectors. Easily field-
replaceable (see "Troubleshooting &
Maintenance: Replacing The Emitter").
Mirror Support Assembly - Provides the
optical path in which gas absorbs infrared
radiation from the emitter. An intrinsically
safe heater prevents condensation on the
mirror. Two versions exist, the standard
nickel-plated aluminum and the optional 316
stainless steel.
Filters - Allow gas to diffuse into the mirror
support assembly while protecting the optics
from dust, oil, and dirt. Filter material
(Porex™) is hydrophobic so filters are
suitable for all weather conditions. Note that
use of filters slows sensor response. Refer
to page 10 for information detailing their use.
Dust Shield - Provides protection against
indoor dust (See Figure 1).
Rain Guard - Provides protection against
rain (See Figure 2).
Deluge Guard- Provides protection in hose-
down areas (See Figure 3).
ESC
IR
SERIES 4600-IR
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9
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Transmitter Installation
Installation Considerations
Prior to installing GasPlus-IR, consideration should be given to the following
items when choosing its location:
1. Orientation - In outdoor applications always mount the instrument's optical
bench pointing downwards.
2. Gas Density - For gases with densities greater than air, the Instrument
should be installed approximately 18" from floor level. In these applications
care should be taken to protect the sensors from physical damage. For gases
with densities less than air, the Instrument should be installed at a high level or
close to the potential leak source. For gases with densities equal to air, mount
as close to potential leak source as practical.
3. Potential Gas Sources - The location and
nature of potential vapor/gas sources (e.g.,
pressure, amount, source, temperature, and
distance) need to be assessed. Locate the
transmitter where air currents are most likely to
contain the highest concentration of escaping gas.
4. Ambient Temperature - Ensure that the
system is located within an area that complies
with the specified operating temperature range.
5. Vibration - Mount the instrument in a manner
that minimizes vibration.
6. Accessibility - When determining mounting
location, consider future maintenance
requirements.
7. Avoid water. Water inside the infrared optics will adversely affect
performance. Although the optics are heated to prevent condensation on the
mirror, the use of a rain shield is still recommended for outdoor installations.
NOTE: The rain shield is included with the instrument.
8. Avoid strong electromagnetic fields. Although the instrument is
designed to be RFI/EMI resistant, mounting the gas transmitter near power
transformers or other strong EM fields may cause undesirable results.
9. Conduit seals and drain loops. Explosion proof conduit and other
materials required for electrical wiring in hazardous areas should be installed
in accordance with National Electrical Code (NEC) and Canadian Electrical
Code (CEC) requirements. All conduit connections should be sealed and
contain a drain loop to protect the transmitter electronics from moisture.
10. Direct bold sunlight. Scott Instruments recommends using a sunshade
if the instrument will be mounted in direct sunlight.
Air
Propane
Butadiene
Butane
IPA
Pentane
Hexane
Toluene
Methane
Ethane
Ethylene
Carbon Dioxide
Propylene
Acetone
MEK
Vapor Densities
Relative To Air
0.6
1.0
1.0
1.5
1.5
2.0
2.1
2.5
1.0
1.6
1.9
2.0
2.5
3.0
3.1
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10
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Using the Rain Shield
and Filters
Using different combinations of the transmitter's
filters optimizes air flow to the detector.
1. For Outdoor Use - Non-Hose Down
Enviroments: Use the rain guard (096-2709),
but not optics assembly inner filter (077-0166).
The transmitter is mounted vertically. See Figure
2 for list of parts and Figure 5 for dimensions.
2. For Outdoor /Indoor Use - Hose Down
Environments: Use the deluge guard (096-
2727), but not optics assembly inner filter (077-
0166). The transmitter is mounted vertically.
See Figure 3 for list of parts and Figure 5 for
dimensions.
3. For Clean Indoor Use: For use in
applications were no wash-downs or liquid spray
is expected. Use the optics assembly inner filter
(077-0166) and dust shield cage (074-0340),
see Figure 1. The transmitter is typically
mounted vertically, or should the application
require, the transmitter may be mounted
horizontally to provide a more unrestricted flow
of gas over the detector. Mounting the
transmitter horizontally is application dependent
and should only be done in indoor applications
and where there is no potential for the transmitter's
optics assembly to be exposed to liquid.
4. For Dirty Indoor Use: For use in
applications were no wash-downs or liquid spray
is expected. Use the inner filter (077-0166), dust
shield cage (074-0340) outer filter (077-0209)
and filter disk (077-0210). The transmitter is
typically mounted vertically, or should the
application require, the transmitter may be
mounted horizontally to provide a more
unrestricted flow of gas over the detector.
Mounting the transmitter horizontally is
application dependent and should only be done in
indoor applications and where there is no potential
for the transmitter's optics assembly to be exposed
to liquid.
5. For Indoor Use - Remote Bump Testing
Installation: Typical application is a gas
compressor installation where the sensor is
mounted in the ceiling. Use deluge guard (096-
2727) and attach tubing to the 1/4" FNPT fitting.
Use inner filter (077-0166). Apply bump check
gas at a minimum flowrate of 2 LPM. THIS IS
NOT FOR CALIBRATION PURPOSES NOR
ACCURACY VERIFICATION.
Figure 1 - Dust Filter Assembly
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11
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Figure 2 -Rain Guard - P/N 096-2709
Figure 3 - Deluge Guard - P/N 096-2727
POREX FILTER MEMBRANE
w/ DRAINAGE HOLE
(P/N 077-0210-1)
INNER FILTER CAGE
POREX FILTER
(P/N 077-0209)
O-RING
(P/N 009-0024, VITON)
OUTER SHIELD
SUBASSEMBLY
OUTER SHIELD
SUBASSEMBLY
POREX FILTER MEMBRANE
w/ DRAINAGE HOLE
(P/N 077-0210-1)
INNER FILTER CAGE
POREX FILTER
(P/N 077-0209)
1/4" NPT PLUG
O-RING
(P/N 009-0024, VITON)
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12
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Wiring and Power
Current Draw
Upon instrument start-up, the GasPlus-IR will experience a 500 mA transient
current draw. Immediately thereafter, current draw will drop to the
instrument's 250 mA iMAX , eventually "settling" down" to the 130 mA typical
current draw.
Maximum Wire Length
AWG wire size requirements are dependent upon power supply voltage and
wire length.
The maximum distance between the transmitter and its power supply is
determined by the maximum allowable interconnecting loop-voltage drop. If
the voltage drop is exceeded, the transmitter will not operate. To determine
the maximum loop-voltage drop, subtract the transmitter's minimum operating
voltage (18 VDC) from the power supply's minimum output voltage. For
example; if the power supply's minimum output voltage is 24 VDC, then the
maximum voltage drop across the power supply is 6 volts.
To determine actual maximum wire length, divide the maximum allowable
voltage drop by the transmitter's maximum current draw, then by the
resistance of the wire (ohms/foot), then divide by 2.
Switches and Circuit Breakers: UL and EN Requirements
EN 61010-1, 1995 edition and UL 3111-1, 1994 edition (Safety Requirements
for Electrical Equipment for Measurement, Control and Laboratory Use-Part 1:
General Requirements) contain the following requirement:
Except as specified in 6.12.1.1, equipment shall be provided with a means
for disconnecting it from each operating energy supply source, whether
external or internal to the equipment. The disconnecting means shall
disconnect all current-carrying conductors.
For the GasPlus-IR to comply with EN 61010-1, 1995 edition and UL 3111-1,
1994 edition:
1. A switch or circuit breaker must be included in the GasPlus-IR
installation,
2. The switch or circuit breaker must be in close proximity to the equipment
and within easy reach of the operator, and
3. The switch or circuit breaker must be marked as the disconnecting
device for the GasPlus-IR.
Minimum Operating Voltage
Power Supply Voltage
Max allowable volt drop (MAV)
(MAV ÷ Max Current draw)
÷ Ohms per ft
÷2
= Max Wire Length
Figure 4 -
Calculating
Maximum Wire
Length
VMIN Source Voltage 24 VDC
VMIN Transmitter 18 VDC
IMAX Transitter 250 mA
RMAX of W ire 24 Ohms
Wire Ohms/ft Max Length Ft (M)
18 AW G (0.00639 Ohm /ft) 1878 (572)
20 AW G (0.01015 Ohm /ft) 1182 (360)
22 AW G (0.01614 Ohm /ft) 743 (227)
Stand-Alone 24 VDC Pow e r Supply
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13
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Current Sourcing and Sinking Modes (see Figure 7)
The GasPlus-IR may be wired in a current sourcing (most typical) or a current
sinking mode. As the names suggest, these 2 modes describe the direction
of current flow in the 4-20 mA loop connecting the GasPlus-IR transmitter
and its receiver. Principally, this is dictated by which end of the loop is
connected to the positive supply voltage (the source).
Current sourcing mode (TYPICAL). When the transmitter is wired in
current sourcing mode, a positive voltage supply is connected to the
transmitter’s mA+ terminal [TB1-3]. Note that this may be the same
supply powering the instrument or a different one (see Isolated and Non-
Isolated Loop Power). Current flows into the mA terminal [TB1-3] and out
of the mA- terminal [TB1-4], controlled by the virtual resistance of the
instrument. From the transmitter’s mA- terminal [TB1-4], current flows into
the receiver’s + terminal, and then out of the receiver’s - terminal to the
power supply negative (common). Most facilities wire instruments in the
current sourcing mode.
Current sinking mode. When the transmitter is wired in the current
sinking mode, the positive supply voltage is connected to the receiver’s +
terminal. Note that this may be the same supply powering the instrument
or a different one (see Isolated and Non-Isolated Loop Power). Current
flows through the receiver and out of the - terminal to the transmitter’s
mA+ terminal [TB1-3]. Controlled by the virtual resistance of the
instrument, current flows out of the transmitter’s mA- terminal [TB1-4] to
the supply negative (common).
Isolated and Non-Isolated Loop Power
When the current loop power supply is different than the one used to power
the transmitter, the loop is “isolated.” When the same power supply is used
for both the current supply and the instrument, the loop is “non-isolated.”
Many PLCs require an isolated loop.
The GasPlus-IR can be wired with either isolated or non-isolated power. Note
from Figure 7 that isolated power requires 4 wires, whereas non-isolated
power can use a 3-wire configuration.
Mounting the Transmitter
General
Before installing (or servicing) the transmitter, ground it and follow all
appropriate procedures to declassify the area (if necessary). Make all
mounting connections (e.g., wiring conduit, mounting bolts, etc.) then mount
the transmitter using the plastic spacer block (on wall mount configurations).
Installing the Transmitter
In most applications, the display and controls will be integral to the transmitter.
After physically mounting the transmitter:
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14
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
1. Unscrew transmitter cover and turn power switch to the "OFF" position.
DO NOT REMOVE OR INSERDO NOT REMOVE OR INSER
DO NOT REMOVE OR INSERDO NOT REMOVE OR INSER
DO NOT REMOVE OR INSERT THE BOT THE BO
T THE BOT THE BO
T THE BOARD STARD ST
ARD STARD ST
ARD STACK while theACK while the
ACK while theACK while the
ACK while the
transmitter is powered ! Place the power switch to the OFFtransmitter is powered ! Place the power switch to the OFF
transmitter is powered ! Place the power switch to the OFFtransmitter is powered ! Place the power switch to the OFF
transmitter is powered ! Place the power switch to the OFF
position prior to rposition prior to r
position prior to rposition prior to r
position prior to removing the Display / CPU boaremoving the Display / CPU boar
emoving the Display / CPU boaremoving the Display / CPU boar
emoving the Display / CPU board stack. Seed stack. See
d stack. Seed stack. See
d stack. See
Figure 3.Figure 3.
Figure 3.Figure 3.
Figure 3. Do not swap CPU and power supplyDo not swap CPU and power supply
Do not swap CPU and power supplyDo not swap CPU and power supply
Do not swap CPU and power supply
boards between different units. They come fromboards between different units. They come from
boards between different units. They come fromboards between different units. They come from
boards between different units. They come from
the fthe f
the fthe f
the factoractor
actoractor
actory calibry calibr
y calibry calibr
y calibraa
aa
ated as a mated as a ma
ted as a mated as a ma
ted as a matctc
tctc
tched set.hed set.
hed set.hed set.
hed set.
2. Grasp the top display board, and pull outward while gently rocking it from
top to bottom. Both the top display board and the center CPU board will
remove, exposing the electrical connectors on the Power Supply board
in the bottom of the housing. The terminal blocks pull out for easy
access.
3. Make wire connections (18 to 22 AWG wire is recommended for
electrical connections). Ensure that proper wire gauge is used and that
all wire, electrical grounds, and sensor connections are secure and
intact.
4. Replace the 2 stacked boards and return the power switch to the ON
position.
5. Screw transmitter cover on, ensuring a tight seal.
Installing Transmitters with Remote Display (see Figure 8)
The remote display option enables users to mount the GasPlus-IR's
controls and display up the 50 feet away from the sensor. The 50 foot
maximum should not be exceeded. After physically mounting the
transmitter and remote display enclosures:
1. Unscrew the (master) transmitter cover and turn power switch to the
"OFF" position.
DO NOT REMOVE OR INSERDO NOT REMOVE OR INSER
DO NOT REMOVE OR INSERDO NOT REMOVE OR INSER
DO NOT REMOVE OR INSERT THE BOT THE BO
T THE BOT THE BO
T THE BOARD STARD ST
ARD STARD ST
ARD STACK while theACK while the
ACK while theACK while the
ACK while the
transmitter is powered ! Place the power switch to the OFFtransmitter is powered ! Place the power switch to the OFF
transmitter is powered ! Place the power switch to the OFFtransmitter is powered ! Place the power switch to the OFF
transmitter is powered ! Place the power switch to the OFF
position prior to rposition prior to r
position prior to rposition prior to r
position prior to removing the Display / CPU boaremoving the Display / CPU boar
emoving the Display / CPU boaremoving the Display / CPU boar
emoving the Display / CPU board stack. Seed stack. See
d stack. Seed stack. See
d stack. See
Figure 3.Figure 3.
Figure 3.Figure 3.
Figure 3. Do not swap CPU and power supplyDo not swap CPU and power supply
Do not swap CPU and power supplyDo not swap CPU and power supply
Do not swap CPU and power supply
boards between different units. They come fromboards between different units. They come from
boards between different units. They come fromboards between different units. They come from
boards between different units. They come from
the fthe f
the fthe f
the factoractor
actoractor
actory calibry calibr
y calibry calibr
y calibraa
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ated as a mated as a ma
ted as a mated as a ma
ted as a matctc
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tched set.hed set.
hed set.hed set.
hed set.
POWER
SWITCH
Place in the OFF position
before removing Display /
CPU board stack. Ensure
power switch is in
the OFF position prior to
replacing board stack.
POWER
SWITCH
Place in the OFF position
before removing Display /
CPU board stack. Ensure
power switch is in
the OFF position prior to
replacing board stack.
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15
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
2. Disconnect the ribbon cable located on the top (CPU) board in the
transmitter enclosure. Grasp the board and pull outward.
3. Make power, loop, and relay wire connections (18 to 22 AWG wire is
recommended), then connect the 9 conductor (master-to-remote) cable
as shown in Figure 10. Replace the CPU board.
4. Unscrew the (remote display) transmitter cover and remove the display
board. Connect the 9 conductor (master-to-remote) cable as shown in
Figure 10. Replace the display board and screw the enclosure cover
on, ensuring a tight seal.
5. Turn the power switch to the ON position on the (master) transmitter and
screw the enclosure cover on, ensuring a tight seal.
Powering The Transmitter
When power is applied to the transmitter, all segments and indicators on the
display will turn on for 2 seconds, then will turn off for 2 seconds. The
transmitter will subsequently enter a 30 second warm-up period
(countdown shown on the display).
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16
Model 4688-IR / 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Installation Drawings
Figure 5 - Instrument Dimensions
IR
ESC
5.44 [138.2]
5.63 [143]
11.25 [285.8] REF.
4.06 [103.1]
4.25 [108] REF.
(2) .312 DIA. [7.9]
MOUNTING HOLES
3/4" NPT X-PROOF UNION
(048-0040). INSERT KWIKO
FIBER FILLER THEN FILL WITH
SEALING CEMENT (096-2211).
ALL COMPONENTS PROVIDED.
.50
[13]
ENCLOSURE
MOUNTING
BLOCK
(074-0289)
(2) 3/4" NPT CONDUIT FITTINGS -
ONE EACH SIDE (CONDUIT
CUSTOMER SUPPLIED)
ALL DIMENSIONS ARE SHOWN IN
INCHES [mm] AND ARE NOMINAL.
5.63 [143]
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17
Model 4688-IR / Model 4679-IR
Operation & Maintenance Manual
Manual #087-0007G, 10/2003
Figure 6 - RS-485 Communications Connections
Figure 7 - RS-232
Communications Connections
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