Det-Tronics PIR9400 User manual

INSTRUCTIONS
PointWatch™ Infrared
Hydrocarbon Gas Detector
PIR9400
11/96 Form 95-8440
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APPLICATION ..........................................................................1
FEATURES...............................................................................1
SPECIFICATIONS....................................................................1
DESCRIPTION..........................................................................4
Detection Method...............................................................4
Current Loop Output..........................................................4
Operating Modes...............................................................4
INSTALLATION.........................................................................5
Detector Location...............................................................6
0 to 100% LFL Linearized Output Options.........................6
Junction Boxes ..................................................................7
General Wiring Requirements ...........................................8
Detector Wiring Procedure ................................................8
Detector Separation (Optional)..........................................8
STARTUP PROCEDURE .......................................................10
CALIBRATION........................................................................10
Calibration Equipment .....................................................10
Calibration Procedures....................................................11
TROUBLESHOOTING............................................................15
MAINTENANCE......................................................................15
Disassembly and Cleaning Procedure.............................16
To Replace the IR Module...............................................17
DEVICE REPAIR AND RETURN............................................18
Office Locations...............................................................18
ORDERING INFORMATION...................................................19
PointWatch Detector........................................................19
Junction Boxes ................................................................19
Calibration Equipment .....................................................19
Spare Parts......................................................................19
ASSISTANCE .........................................................................19
APPENDIX..............................................................................20
Approval...........................................................................20
Attachment/Options.........................................................20
Calibration........................................................................20
List of Illustrations
Figure 1 4 to 20 ma Current Loop Resistance.....................2
Figure 2 PointWatch Wiring Requirements .........................3
Figure 3 Aluminum PointWatch Unit Dimensions
in Inches (MM).......................................................3
Figure 4 Stainless Steel PointWatch Unit Dimensions
in Inches (MM).......................................................3
Figure 5 Junction Box Dimensions in Inches (MM) .............4
Figure 6 Tall PointWatch Junction Box with Window ..........5
Figure 7 Short PointWatch Junction Box ............................5
Figure 8 PointWatch Gas Absorption Curves......................6
Figure 9 Aluminum PointWatch Disassembly......................7
Figure 10 Stainless Steel PointWatch Disassembly..............7
Figure 11 IR Module and Base Assemblies ..........................7
Figure 12 IR Module Removal...............................................7
Figure 13 Gas Selection Switch Location at the Bottom
of the Electronics Assembly ..................................7
Figure 14 Typical PointWatch Wiring,
Standalone Configuration......................................9
Figure 15 Typical PointWatch Wiring,
PointWatch with Det-Tronics Junction Box ...........9
Figure 16 Junction Box Terminals and Calibration Switch ....9
Figure 17 Typical PointWatch Wiring
with Det-Tronics Infiniti Transmitter.....................10
Figure 18 Typical PointWatch Wiring
with Eagle Communication Module.....................10
Figure 19 Options for Detector Separation..........................10
Figure 20 Sensor Separation with Infiniti Transmitter
and PointWatch...................................................11
Figure 21 Aluminum PointWatch Detector Calibration Port.13
Figure 22 Aluminum PointWatch Detector Calibration
Configuration.......................................................13
Figure 23 Stainless Steel PointWatch Detector Calibration
Configuration.......................................................13
Figure 24 Aluminum PointWatch Detector Disassembly
for Cleaning.........................................................16
Figure 25 Stainless Steel PointWatch Detector
Disassembly for Cleaning....................................17
List of Tables
Table 1 Current Loop Output Levels and Corresponding
Status Indications..................................................2
Table 2 Mounting Orientation.............................................6
Table 3 Installation Options for Intrusive and
Non-intrusive Calibration.......................................8
Table 4 Calibrate or Check...............................................11
Table 5 Calibration Sequence, Inhibited Current Output..12
Table 6 Troubleshooting Table.........................................15
Table of Contents
ii

INSTRUCTIONS
PointWatch™ Infrared
Hydrocarbon Gas Detector
PIR9400
©Detector Electronics Corporation 1996 11/96 95-8440
APPLICATION
The PointWatch Detector is a diffusion-based point-type
infrared gas detector that provides continuous monitor-
ing of combustible hydrocarbon gas concentrations in
the range of 0 to 100% LFL. The detector provides a 4
to 20 milliampere output signal, corresponding to the
detected gas concentrations. The explosion-proof sen-
sor housing meets FM, CSA and CENELEC require-
ments for use in hazardous environments.
PointWatch is ideally suited for use in harsh environ-
ments and where the cost of required maintenance for
conventional catalytic detectors is prohibitive. The
PointWatch IR Detector will perform reliably in the pres-
ence of silicone and other catalytic poisoning agents
and can also operate in oxygen free environments or
where high background gas levels are present. There
are no known poisons that affect this technology.
The PointWatch detector can be used alone or as part
of a larger system such as Det-Tronics’ Infiniti Gas
Transmitter, R8471 Controller, or Eagle 2000 Hazard
Monitoring System.
FEATURES
•Requires no routine calibration to ensure proper oper-
ation.
•Continuous self-test automatically indicates a fault or
fouled optics condition.
•Unique multi-layered filtering system protects optics
from dirt and water ingress.
•Internal heating system minimizes condensation,
allowing reliable operation through temperature
extremes.
•Performs well in the presence of high concentrations
or constant background levels of hydrocarbons and in
oxygen depleted atmospheres.
•There are no known poisons, e.g. silicones or
hydrides, that compromise the integrity of the mea-
surement.
• Standard 4 to 20 milliampere output (current source).
• Standard 0 to 100% LFL detection range.
•Compact, lightweight, explosion-proof housing is
designed for duty in harsh environments.
SPECIFICATIONS
INPUT VOLTAGE—
+24 vdc nominal (range +18 to +32 vdc).
POWER CONSUMPTION (Watts)—
Input Voltage: 18 vdc 24 vdc 32 vdc
Nominal 3.5 4.6 6.2
Maximum 4.0 5.5 7.0
DETECTION RANGE—
0 to 100% LFL.
GASES —
Will respond to most hydrocarbon gases. Outputs lin-
earized for 0 to 100% LFL are provided for methane,
ethane, propane/butane, ethylene, propylene.
All devices are shipped with a 0 to 100% LFL linearized
output for methane. Other linearized outputs are field
selectable by means of a switch.
CURRENT OUTPUT (NON-ISOLATED)—
Linear 4 to 20 ma current source.
• 4 to 20 ma output indicates 0 to 100% LFL
detection range (for linearized gases)
• 23.2 ma indicates over-range condition (120%
LFL)
• 0 to 2.4 ma levels indicate calibration, fault and
fouled optics conditions.
Refer to Table 1 for a detailed description of current out-
puts.
Maximum loop resistance: 600 ohms at +24 vdc. See
Figure 1 for further information.

The following specifications for Accuracy, Stability
and Repeatability are based on a 0 to 100% LFL
methane calibration
ACCURACY (Room Temperature)—
±3% LFL from 0 to 50% LFL, ±5% LFL from 51% to
100% LFL.
RESPONSE TIME (Seconds)— T50 T90
Aluminum
Outside weather baffle only 6 17
All weather protection installed 9 21
Stainless Steel
All weather protection installed 2 5
(Det-Tronics verified)
STABILITY—
Temperature
Zero: ±2% LFL from
–40°F to +167°F (–40°C to +75°C).
Span: ±5% LFL at 50% LFL from
–13°F to +167°F (–25°C to +75°C),
±10% LFL at 50% LFL from
–40°F to –13°F (–40°C to –25°C).
Time (10 months) ±2% LFL (Det-Tronics verified).
REPEATABILITY (Room Temperature)—
Zero: ±1% LFL.
Span: ±2% LFL at 50% LFL.
(Det-Tronics verified)
WIRING—
The PointWatch detector has five 22 AWG wires, 20
inches long for wiring into a junction box or the Infiniti
transmitter.
Red = + 24 volts dc
Black = – (common)
White = 4 to 20 milliampere signal output
Yellow = Calibration input
Green = Chassis ground
Power Wiring: 18 AWG minimum is recommended for
power wiring. Larger diameter wire may be required to
maintain a minimum of 18 vdc (including ripple) at the
sensor for all operating conditions (see Figure 2). For
maximum EMI/RFI protection, shielded cable is recom-
mended.
OPERATING TEMPERATURE RANGE—
–40°C to +75°C (–40°F to +167°F).
HUMIDITY (Non-Condensing)—
0 to 99% relative humidity (Det-Tronics verified)
5 to 95% relative humidity (FMRC/CSA verified).
RFI/EMI PROTECTION—
EN50081-1. Class B, EN50082-1 (IEC 801-2, 3, 4). (ETL
verified -EMC).
Operates properly with 5 watt walkie talkie keyed at 1
meter.
INGRESS PROTECTION—
IP66 (DEMKO certified per EN60529).
ENCLOSURE MATERIALS—
Aluminum (clear anodized) enclosure and weather pro-
tection baffles. Content: 0.8% to 1.2% Mg, 0.15% to
0.40% CU.
Stainless Steel (316 electropolished) enclosure, polyph-
thalamide (PPA) weather protection baffle.
2
1000
900
800
700
600
500
400
300
18 20 22 24
INPUT VOLTAGE
26 28 30 32
LOOP RESISTANCE (OHMS)
A1750
Figure 1—4 to 20 ma Current Loop Resistance
Table 1—
Current Loop Output Levels and Corresponding Status Indications
Current Level Status
23.2 ma Over-range (120% LFL)
20.0 ma Full scale (100% LFL)
4.0 ma Zero gas level (0% LFL)
2.2 ma Zero calibration in progress
2.0 ma Span calibration in progress
1.8 ma Calibration complete - remove gas
1.6 ma Calibration fault
1.0 ma Fouled optics
0.8 ma 24 vdc line low (less than 17.5 vdc)
0.6 ma Calibrate input active at power-up
(probable wiring fault)
0.4 ma Active channel fault
0.2 ma Reference channel fault
0.0 ma CPU system fault, warmup

CERTIFICATION—
PointWatch Aluminum Stainless Steel
CENELEC1X X
FM2X
CSA3X
Gosstandart4X X
1CENELEC: Certificate No. 95D.119043
EEx d IIB + H2 T6 (Tamb –40°C to +40°C)
EEx d IIB + H2 T5 (Tamb –40°C to +75°C).
Ingress protection IP66.
2FM: Explosion-proof for Class I, Div. 1, Groups B,
C & D per FM 3615. Performance per FM
6320. (See Appendix for approval descrip-
tion.)
3CSA: Explosion-proof for Class I, Div. 1, Groups B,
C & D per CSA C22.2 No. 30. Performance
per CSA C22.2 No. 152.
4Gosstandart: Certificate No. A-0272; Performance
Certificate No. 1039.
1Ex d IIB T6/H2 (Tamb. -40°C to +40°C)
1Ex d IIB T5/H2 (Tamb. -40°C to +75°C).
Junction Box Aluminum Stainless Steel
CENELEC5X N/A
FM6X N/A
CSA7X N/A
Gosstandart8Pending N/A
5CENELEC: Certificate No. 96D1115
EEx d IIC T6 (Tamb –60°C to +40°C)
EEx d IIC T5 (Tamb –60°C to +75°C).
Ingress protection IP66.
6FM: Explosion-proof for Class I, Div. 1, Groups B,
C & D per FM 3615.
7CSA: Explosion-proof for Class I, Div. 1, Groups B,
C & D per CSA C22.2 No. 30.
8Gosstandart:
1Ex d IIC T6 (Tamb –60°C to +40°C)
1Ex d IIC T5 (Tamb –60°C to +75°C).
MOUNTING—
Detector can be threaded into any approved junction
box suitable for the specific applications. (Junction box
spacers may be required for flush mounting.)
PointWatch thread options:
• 3/4 inch NPT
• M20 (for use outside North America).
SHIPPING WEIGHT—
Aluminum: 2.8 pounds (1.3 kilograms).
Stainless Steel: 4.8 pounds (2.2 kilograms).
DIMENSIONS—
See Figures 3 and 4 for the dimensions of the
PointWatch Detector and Figure 5 for dimensions of the
PointWatch Junction Box.
TERMINALS—
Terminals UL/CSA rated for 14 to 22 AWG wire; termi-
nals DIN/VDE rated for 2.5 mm2wire.
A1752
8.95
(227)
2.5
(64)
3/4 – NPT
M20 X 1.5
M25 X 1.5
A1751
5000
4800
4600
4400
4200
4000
3800
3600
3400
3200
3000
2800
2600
2400
2200
2000
1800
1600
1400
1200
1000
800
600
400
200
018 20 22 24
POWER SUPPLY VOLTAGE (VDC)
26 28 30 32
WIRING DISTANCE (FT)
18 AWG
16 AWG
14 AWG
12 AWG
3 95-8440
Figure 2—PointWatch Wiring Requirements
Figure 3—Aluminum PointWatch Unit Dimensions in Inches (MM)
A1753
9.50
(241)
3.25
(83)
Figure 4—Stainless Steel PointWatch Unit Dimensions in Inches (MM)

DESCRIPTION
DETECTION METHOD
PointWatch operates on the infrared absorption principle.
A beam of modulated light is projected from an internal
infrared source to a reflector, which sends it back to a
pair of infrared sensors. One of the sensors is designat-
ed reference and the other active, with different optical fil-
ters in front of the two sensors to make them selective to
different infrared wavelengths. The reference wavelength
is unaffected by combustible gases, while the active
wavelength is absorbed by combustible gases. The ratio
of the active to the reference wavelength is computed
within the PointWatch detector to determine the concen-
tration of gas present. This value is then converted into a
4 to 20 milliampere current output for connection to exter-
nal display and control systems.
CURRENT LOOP OUTPUT
During normal operation, the PointWatch detector has a
current output from 4 to 20 milliamperes that is propor-
tional to gas concentrations from 0 to 100% LFL. A cur-
rent output other than 4 to 20 milliamperes indicates
either negative gas level, a fault or over-range condition,
or that the unit is in the calibrate mode as indicated in
Table 1.
OPERATING MODES
Warmup
When power is applied to the detector, it enters a
Warmup mode (for approximately one minute) in which
it performs diagnostic checks and allows the sensors to
stabilize before beginning normal operation. The cur-
4
Figure 5—Junction Box Dimensions in Inches (MM)
6.5
(16.5)
3.38 (8.4)
4.1 (10.4)
B1520
4.5 (11.4)
4.1
(10.4)
3/4 INCH NPT (2)
0.3 DIA.
(0.8)
TALL COVER J-BOX
3.7
(9.4)
3.3
(8.4)
4.1
(10.4)
B1482
4.5
(11.4)
4.1
(10.4)
0.3 DIA.
(0.8)
SHORT COVER J-BOX
3/4 INCH NPT (2)
20 MM OPTIONAL

rent output during this period is 0 milliamperes. At the
end of the warmup period with no faults present, the
detector automatically enters the Normal operating
mode. If a fault is present after the warmup, the detec-
tor current output will indicate a fault.
Normal
In the normal operating mode, the 4 to 20 milliampere
signal level corresponds to the detected gas concentra-
tion. The detector continuously checks for system faults
or initiation of calibration, and automatically changes to
the appropriate mode.
Fault
Faults detected during warmup, normal operation, or
calibration are indicated by the current loop output as
shown in Table 1.
Calibration
When the calibration lead is momentarily connected to
the negative lead (common) of the power supply, the
microprocessor executes the zero and span calibration
sequence. The output current during calibration
defaults to an inhibited state. See Table 1.
NOTE
The current output during calibration can be set for
live operation, however, this method is not usually
recommended. Refer to the “Calibration” section
for further information.
Two junction box types for use specifically with the
PointWatch detector are available from Det-Tronics.
• Tall Cover/Window Junction Box for one person,
non-intrusive calibration. This junction box includes
a magnetic reed calibration switch, calibration LED
and a windowed cover. Activating the magnetic
reed switch with the calibration magnet and viewing
the LED through the window provides one person,
non-intrusive calibration capability. See Figure 6.
• Short Cover Junction Box for PointWatch requires
two people to accomplish non-intrusive calibration.
This junction box includes a magnetic reed calibra-
tion switch, calibration LED and a solid cover.
Activating the magnetic reed calibration switch with
the calibration magnet or touching the calibration
lead to the negative lead (common) of the power
supply using an external switch are methods used
to initiate calibration. This junction box can also be
used for sensor separation. See Figure 7.
INSTALLATION
IMPORTANT
Hydrocarbon-based grease will emit hydrocarbon
vapors which will be measured by PointWatch and
will result in inaccurate gas level readings. Use
only low vapor pressure silicone grease when
lubricating threads on the PointWatch detector
and associated junction box. Do not get this
grease on the optics of the detector. A suitable
grease is listed in the “Spare Parts” section at the
end of this manual.
IMPORTANT
In applications where both PointWatch and catalyt-
ic type sensors are used, ensure that the silicone
grease used to lubricate the PointWatch detector
threads does not come into contact with the cat-
alytic sensors or poisoning of the catalytic sensors
will result. It is strongly recommended that mainte-
nance personnel wash their hands between han-
dling the two types of sensors.
5 95-8440
Figure 6—Tall PointWatch Junction Box with Window Figure 7—Short PointWatch Junction Box

DETECTOR LOCATION
It is essential that the device be properly located to
enable it to provide maximum protection. The most
effective number and placement of sensors varies
depending on the conditions at the job site. The indi-
vidual designing the installation must rely on experience
and common sense to determine the type and quantity
of sensors and the best sensor locations to adequately
protect the area. The following factors should be con-
sidered for every installation:
1. What kind of gas is to be detected? If it is lighter
than air, place the sensor above the potential gas
leak. Place the sensor close to the floor for gases
that are heavier than air or for vapors resulting from
flammable liquid spills. However, note that air cur-
rents can cause a gas that is heavier than air to
rise. In addition, if the gas is hotter than ambient air
or mixed with gases that are lighter than air, it could
also rise.
2. How rapidly will the gas diffuse into the air? Select
a location for the sensor as close as practical to the
anticipated source of a gas leak.
3. Ventilation characteristics of the immediate area
must also be considered. Movement of air may
cause gas to accumulate more heavily in one area
than another. The detector should be placed in the
areas where the most concentrated accumulation of
gas is anticipated. Also take into consideration the
fact that many ventilation systems do not operate
continuously.
4. Proper orientation is dependent upon the
PointWatch model used and the environmental con-
cerns at the installation. See Table 2.
5. The sensor should be accessible for maintenance.
6. Excessive heat or vibration can result in premature
failure of any electronic device and should be
avoided if possible.
NOTE
For additional information on determining the quan-
tity and placement of gas detectors in a specific
application, refer to the article titled “The Use of
Combustible Detectors in Protecting Facilities from
Flammable Hazards” contained in the Instrument
Society of America (ISA) Transaction, Volume 20,
Number 2.
0 TO 100% LFL LINEARIZED OUTPUT OPTIONS
The PointWatch detector is factory configured for 0 to
100% LFL methane. This configuration can be changed
to other gases in the field by changing the setting on the
rotary gas selection switch, which is located on the
electronics module, and calibrating the device with the
new standard gas selected.
PointWatch has a good response to hydrocarbon gases
and to the vapors of hydrocarbon liquids. However, the
response varies depending on the structure of the
hydrocarbon molecule (see Figure 8). The raw
response of PointWatch is linearized to provide a 0 to
100% LFL output for five standard gases: methane,
ethane, propane/butane, ethylene, propylene.
Changing Linearized Output Gas Selection
IMPORTANT
Remove power before removing and disassem-
bling the PointWatch detector.
1. Loosen the two captive screws on the flat end of the
detector and slide the filter assemblies off. For the
aluminum model, use a standard screwdriver. For
the stainless steel model, use a 7/64 inch hex driv-
er. See Figure 9 (aluminum) or Figure 10 (stainless
steel).
2. Unscrew and remove the electronics mounting
cover by rotating it counter-clockwise. See Figure
11.
3. Slide the electronics mounting cover back to the
base of the mirror assembly and pull the IR module
out of the base as shown in Figure 12.
6
Figure 8—PointWatch Gas Absorption Curves
A1754
60
40
20
00 30 60 90
GAS CONCENTRATION (% LEL) 120
ABSORPTION (%)
PROPYLENE
ETHYLENE
PROPANE
ETHANE
METHANE
Table 2—Mounting Orientation
Model Installation Environment Orientation
Aluminum Heavy rain or hose down Vertical
Blowing dust or sand Horizontal
Stainless Steel All applications Horizontal

4. Using a small screwdriver, rotate the gas selection
switch from position 0 (methane) to the desired
position. Refer to Figure 13. Ensure that the tip of
the arrow on the switch lines up with the position
selected.
5. The module is “keyed” using different sized pins on
the bottom of the module. Slide the IR module into
the base and rotate it until the keyed holes are
aligned, then press securely into place.
NOTE
This assembly fits correctly only in one orientation.
If it is not seating into place, rotate it 180°and try
again.
6. Screw the electronics mounting cover clockwise
onto the base assembly as shown in Figure 11.
7. For the aluminum model, slide the outer filter
assembly over the mirror assembly. The outer filter
should be oriented with the solid portion toward the
base of the unit. If it is not oriented correctly, the fil-
ter assembly will not slide onto the unit. Slide the
inner filter assembly into the outer filter assembly
and rotate until it is seated securely, then fasten the
two captive screws using a standard screwdriver.
See Figure 9.
For the stainless steel model, slide the stainless
steel collar onto the base assembly, then slide the
baffle onto the unit. Place the end cap on the baffle
and rotate it until it is seated securely, then fasten
the two captive screws using a 7/64 inch hex driver.
See Figure 10.
8. Calibrate the detector with 50% LFL of the gas that
matches the calibration gas switch position follow-
ing the instructions in the “Calibration” section of
this manual.
JUNCTION BOXES
The PointWatch detector is designed to be threaded
into a junction box, which can be mounted to a solid,
vibration free wall or post. A 3/8 inch spacer may be
required between the enclosure and the mounting sur-
face to allow adequate room for the sensor and calibra-
tion accessory.
Intrusive and Non-Intrusive Calibration
For hazardous locations, it is important to consider the
options for calibration of PointWatch. The device can
be installed so that calibration can be performed by one
person without opening the explosion-proof enclosure
(non-intrusive calibration). This is accomplished by
incorporating a display or LED that provides information
BASE ASSEMBLY
ELECTRONICS MOUNTING COVER
HYDROPHOBIC SCREEN (ALUMINUM MODEL)
REFLECTOR TUBES (INSIDE)
MIRROR ASSEMBLY
CAPTIVE SCREWS (2)
A1741
STAINLESS STEEL COLLAR
BAFFLE
END CAP
CAPTIVE HEX SCREWS (2) A1739
OUTER FILTER ASSEMBLY
INNER FILTER ASSEMBLY
CAPTIVE SCREWS (2)
A1738
7 95-8440
Figure 10—Stainless Steel PointWatch Disassembly
Figure 9—Aluminum PointWatch Disassembly
Figure 11—IR Module and Base Assemblies
ELECTRONICS MOUNTING COVER
IR MODULE BASE A1742
Figure 12—IR Module Removal
ACCESS TO GAS SELECTION SWITCH
GAS SELECTION SWITCH
0 = METHANE (FACTORY SETTING)
1 = ETHANE
2 = PROPANE
3 = ETHYLENE
4 = PROPYLENE
A1740
2
4
6
0
3
5
7
1
Figure 13—Gas Selection Switch Location
at the Bottom of the Electronics Assembly

and/or instructions for calibration. When a display is not
used or the LED is not visible from the outside, the
enclosure must be opened to observe the LED or to
insert a meter to read the output of the device (intrusive
calibration). With this type of installation, either a permit
must be obtained to open the enclosure or the proce-
dure must be accomplished by two people using walkie
talkies for communication.
Depending on the control devices selected, PointWatch
can be installed for either intrusive or non-intrusive cali-
bration. See Table 3 for a listing of the installation
options.
A user-supplied junction box can also be used, provid-
ed it has the appropriate sized entries. This junction
box must be suitable for use in the application and loca-
tion in which it is being installed. Calibration is initiated
by touching the calibration lead to the negative lead
(common) of the power supply. Although this can be
accomplished manually, installation of a switch is rec-
ommended. It is recommended that this switch be a
momentary contact type to prevent it from inadvertently
being left in the calibrate position.
GENERAL WIRING REQUIREMENTS
NOTE
The wiring procedures in this manual are intended
to ensure proper functioning of the device under
normal conditions. However, because of the many
variations in wiring codes and regulations, total
compliance to these ordinances cannot be guaran-
teed. Be certain that all wiring complies with appli-
cable regulations relating to the installation of elec-
trical equipment in a hazardous area. If in doubt,
consult the authority having jurisdiction before
wiring the system.
The use of shielded cable in conduit or shielded
armored cable is recommended for optimum RFI/EMI
protection. In applications where the wiring cable is
installed in conduit, the conduit must not be used for
wiring to other electrical equipment. To assure proper
operation of the detector, the resistance of the connect-
ing wire must be within the specified limits. The maxi-
mum distance between the detector and power source
is determined by the power supply capability and wire
size. See Figure 2 to determine the proper wire size
and maximum wiring distance allowed.
It is important that moisture not be allowed to come in
contact with the electrical connections of the system.
The use of proper piping techniques, breathers, glands,
and seals are required to prevent water ingress and/or
maintain the explosion-proof rating.
DETECTOR WIRING PROCEDURE
IMPORTANT
Do not apply power until the wiring procedure is
complete and has been verified.
1. Determine the best mounting location for the detec-
tor (refer to the “Detector Location” section above).
If it is determined that sensor separation is required,
see the following section for details.
2. The junction box should be electrically connected
to earth ground.
3. Figures 14 through 18 show typical wiring for vari-
ous system configurations using the PointWatch
detector. Refer to the appropriate figure as a guide
to system connection. Figure 14 shows typical
wiring for standalone operation. Figure 15 shows
typical wiring for PointWatch with Det-Tronics sup-
plied junction box. Figure 16 shows the junction box
terminals and calibration switch. Figure 17 shows
typical wiring for PointWatch/Infiniti transmitter oper-
ation. Figure 18 shows typical wiring for
PointWatch/Eagle communication module configura-
tion. The PointWatch wiring color code is:
Red lead = +24 volts dc
Black lead = – (common)
White lead = 4 to 20 ma signal output
Yellow lead* = Calibration input
Green lead = Chassis ground
*If the calibration wire (yellow lead) is not
being used, do not connect this wire to
ground. Trim excess length and insulate
wire so no shorting can occur.
4. Check the detector wiring to ensure proper connec-
tions, then pour the conduit seals and allow them to
dry (if conduit is being used).
DETECTOR SEPARATION (OPTIONAL)
In applications where the detector must be installed in a
different location from the control device, a junction box
must be installed at the detector location to make the
8
Table 3—
Installation Options for Intrusive and Non-Intrusive Calibration
Control Device Non-Intrusive Intrusive or
& 1 person 2 person
Infiniti Transmitter X
PointWatch Junction Box X
w/ tall cover/window
PointWatch Junction Box X
w/ short cover/no window
Eagle 2000 DCU X
Eagle 2000 Communication Module X