RKI Instruments 65-2497RK User Manual

65-2494RK/65-2497RK

Part Number: 71-0179RK
Revision: 0
Released: 2/16/11

Oxygen Detector

Operator’s Manual

www.rkiinstruments.com

WARNING

Read and understand this instruction manual before operating
detector . Improper use of the dete ctor could result in bodily harm
or death.

Periodic calibration and maintenance of the detector is essential
for proper operation and correct readings. Please calibrate and
maintain this detector regularly! Frequency of calibration
depends upon the type of use you have and the sensor types.
T ypical calibration frequencies for most applications a re between
3 and 6 months, but can be required more often or less often
based on your usage.

65-2494RK/65-2497RK Oxygen Detector

Product Warranty

RKI Instruments, Inc. warrants gas alarm equipment sold by us to be free from defects in
materials, workmanship, and performance for a period of one year fr o m date of shipment
from RKI Instruments, Inc. Any parts found defective withi n tha t period will be repaired
or replaced, at our option, free of charge. This warranty does not apply to those items
which by their nature are subject to deterioration or consumption in normal ser v ice, and
which must be cleaned, repaired, or replaced on a routine basis. Examples of such items
are:

W arranty is voided by abuse including mechanical damage, alteration, rough handling, or
repair procedures not in accordance with the operator’s manual. This warranty indicates
the full extent of our liability , a nd we are not r esponsible for removal or r eplacement costs,
local repair costs, transportation costs, or contingent expenses incurred without our prior
approval.

a) Absorbent cartridges d) Batteries
b) Pump diaphragms and valves e) Filter elements
c) Fuses

THIS WARRANTY IS EXPRESSLY IN LIEU OF ANY AND ALL OTHER
WARRANTIES AND REPRESENTATIONS, EXPRESSED OR IMPLIED,
AND ALL OTHER OBLIGATIONS OR LIABILITIES ON THE PART OF
RKI INSTRUMENTS, INC. INCLUDING BUT NOT LIMITED TO, THE
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE. IN NO EVENT SHALL RKI INSTRUMENTS,
INC. BE LIABLE FOR INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
LOSS OR DAMAGE OF ANY KIND CONNECTED WITH THE USE OF
ITS PRODUCTS OR FAILURE OF ITS PRODUCTS TO FUNCTION OR
OPERATE PROPERLY.

This warranty covers instruments and parts sold to users by authorized distributors,
dealers, and representatives as appointed by RKI Instruments, Inc.

We do no t as su me indemnif ic a t ion for any accident or d amage caused b y t he op e r a t ion of
this gas monitor, and our warranty is limited to the replacement of parts or our complete
goods.

65-2494RK/65-2497R K Oxyg en Detector

Table of Contents

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

65-2494RK Oxygen Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Junction Box. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Mounting the Oxygen Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Wiring the Oxygen Detector to a Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Setting the Fresh Air Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Replacing Components of the Oxygen Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Calibration Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Preparing for Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Setting the Fresh Air Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Setting the Zero Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

65-2494RK/65-2497RK Oxygen Detector

Overview

This manual describes the 65-2497RK oxygen detector . This manual also describes how to
install, start up, maintain, and calibrate the oxygen detector when used with a gas
monitoring controller. A parts list at the end of this manual lists replacement parts and
accessories for the oxygen detector.

The 65-2497RK oxygen detector includes the 65-2494RK oxygen detector and a junction
box. This manual may also be used for the 65-2494RK oxygen detecto r which does not
include a junction box and is normally mounted in one of a controller’s conduit hubs. If
you are using a 65-2494RK oxygen detector, disregard all references to the junction box
and junction box terminal strip.

Specifications

WARNING: Do not use this product in a manner not specified in thi s instruction

Table 1 lists specifications for the 65-2494RK and 65-2497RK oxygen detectors.

manual.

Table 1: Specifications

Target Gas Oxygen (O
Sampling Method Diffusion

Detection Range 0-25% oxygen
Response Time 90% in 30 seconds
Accuracy ± 0.5% O

Operating Temperature -4°F to 113°F (-20°C to 45°C)

WARNING: When using the 65-2494RK/65-2497RK, you must follow the instructions

and warnings in this manual to assure proper and safe operation of the
65-2494RK/65-2497RK and to minimize the risk of personal injury. Be sure
to maintain and periodically calibrate the 65-2494RK/65-2497RK as
described in this manual.

)

2

2

65-2494RK/65-2497RK Oxygen Det ec t or • 1

Description

Detector Housing Body

This section describes the components of the 65-2494RK and 65-2497RK detectors. The
65-2497RK i n cludes the 65-2494RK oxyge n detector and a junction box. A two point
terminal s trip is pr o vid ed ins ide the jun ct ion bo x for detect or connect ions. Th e 65-24 94RK
does not include a junction box. Figure 1 below shows the components of the 65-2497RK.

3/4 NPT Conduit Hub

White Green

Figure 1: 65-2497RK Component Location

65-2494RK Oxygen De tector

The 65-2494RK oxygen detector consists of the detector housing body, detector housing
cap, cap gasket, and the plug-in sensor.

Terminal B lock

J-Box

Rubber
Spacer, 3X

Oxygen
Detector

Figure 2: 65-2494RK Oxygen Detector Component Location

2 • 65-2494RK/65-2497RK Oxygen Detect or

Cap Gasket

Plug-in Oxygen Sensor

Detector
Housing Cap

Hydrophobic
Membrane

Detector Housing Body

The detector housing body protects the electronic components within the housing. Use the
mounting threads at the top of the housi ng to screw the oxygen detector into a 3/4” N PT
hub. Two wires extend from the top of the detector housing body. Use these wires to
connect the detector to a controller. One of the wires is white and one of the wires is green.

The housing body includes two sockets installed on a circuit board. These sockets accept
the plug-in sensor’s two pins to provide an electrical connection for the sensor. The circuit
board with the sockets conditions the sensor’s signal before the signal reaches the
controller.

Housing Cap & Cap Gasket

The housing cap screws onto the detector housing. It retains the plug-in sensor and
protects it from damage. A foam gasket inside the housing cap seals against the face of the
sensor when the cap is screwed on the housing body. A hydrophobic membrane on the
outside of the cap face keeps water and particulates away from the sensor face behind the
cap. Unscrew the detector cap to access the plug-in sensor for maintenance or
replacement. A cap gasket seals the interface between the housing and cap.

Plug-in Sensor

The plug-in sensor is secured in the dete ctor assembly by the housing cap. Through a
series of chemical and electrical reactions, the sensor produces an electrical output that
corresponds to the detection range of the detector. The sensing element used is a capillary
type that is not susceptible to output changes with changes in atmospheric pressure.

Installation

Junction Box

Use the junction box to install the oxygen detector at a mounting site that is remote from a
controller and to protect the detector wiring connections. Two conduit hubs allow you to
mount the detector to the junction box and connect the wiring from the detector to a
controller. Three spacers installed on the back of the junction box control the distance of
the junction box from a mounting surface and ensure that there is enough room to install a
calibration cup on the detector during calibration. A terminal block within the junct ion
box facilitates the wiring connections. A cover on the front of the junction box allows
access to the interior of the junction box.

This section describes procedures to mount the oxygen detector in the monitoring
environment and wire the detector to a controller.

Mounting the Oxygen Detector

NOTE: If you are installing a 65-2494RK, it does not include a junction box and is usually

factory installed in one of a controller’s conduit hubs or may be field installed
using the 3/4” NPT threads on the end with the wir es. The 65-2497RK includes a
junction box as shown in Figure 3 below.

1. Select a mounting site that is representative of the monitoring environment. Consider
the following when you select the mounting site.

• Select a site where the detector is not likely to be bumped or disturbed. Ma ke sur e

there is sufficient room to perform start-up, maintenance, and calibration
procedures.

65-2494RK/65-2497RK Oxygen Det e ct or • 3

• Select a site where the target gas is likely to be found first.

NOTE: If your application does not require a specific mounting site, mount the detector

at approximately breathing level.

+

7.30 .25

.75

1.32

1 1/2- 20 Thread fo r

65-2494RK

3/4 NPT

Female

3/4" NPT

3.65

6.80 Max

Ø 1.75

Cal ibra tion Cu p

Oxygen Dete ctor

1 1/2-20 Thread for Calibration Cup

J-Box

65-2497RK

Figure 3: Outline & Mounting Dimensions, 65-2494RK & 65-2497RK

.75

3.10
.38

Rubber
Spacers
3X

2. At the mounting site you select, hang or mount the junction box with the detector
facing down (see Figure 3).

Wiring the Oxygen Detector to a Controller

WARNING: Always verify that power to the controller is OFF before you make wiring

connections.

1. Turn off the controller.

2. Turn off or unplug p ower to the controller.

3. If the detector is mounted remotely from a controller using the junction box, proceed
to step 4.

If the detector is mounted directly to a controller, it is normally factory wired. Confirm
that the detector ’s w hite and green wires are connected to the appropriate controller
detector terminals and skip to “Start Up” on page 6. See Figure 4, the controller
operator’s manual, and the controller’s detector head specification sheet for the
65-2494RK detector for the wiring connections.

4. Remove the junction box cover.

5. Guide a two-conductor, shielded cable or two wires in conduit through the unused
conduit hub of the junction box. Use appropriate conduit fittings and construction

4 • 65-2494RK/65-2497RK Oxygen Detect or

technique for the environmental rating of the junction box. The junction box is rated
NEMA 4X.

6. Connect the two wires to the detector using the terminal block.

CAUTION: If using shielded cable, leave the drain wire insulated and disconne cted at the

detector. You will connect th e o pposite end of the c able’s drain wire at the controller.

7. Secure the junction box cover to the junction box.

8. Route the cable or wires leading from the oxygen detector through one of the conduit
hubs at the controller housing. Use appropriate conduit fitt ings and construction
technique for the environmental rating of the controller. RKI controllers are typically
rated NEMA 4X.

CAUTION: Do not route power and detector wiring through the same conduit hub. The power

cable may disru pt the transmission of the detect or signal to the controller.

9. Connect the wires to the applicable controller terminal strip. See the controller
operator’ s manual and the controller’s detector head specification sheet for the
65-2497RK detector.

Controller Oxygen

Detector Terminals

Controller Housing

Green (-)

White (+ )

Shielded Cable

White

J-Box

Green

Oxygen detector assembly

Figure 4: Wiring the Oxygen Detector to a Controller

10. If using shielded cable, connect the cable’s drain wire to an available chassis ground at
the controller. RKI controllers typically have a ground stud that is a convenient
grounding location.

65-2494RK/65-2497RK Oxygen Det e ct or • 5

Start Up

This section describes procedures to start up the oxygen detector and place the detector
into normal operation.

Introducing Incoming Power

1. Complete the installation procedures described earlier in this manual.

2. Verify that the power wiring to the controller is correct and secure. Refer to the
controller operator’s manual.

3. Turn on or plug in the incoming power, then turn on the controller.

4. Verify that the controller is on and operating properly. Refer to the con troller
operator’s ma nual.

CAUTION: Allow the detector to warm up for 5 minutes before you continue with the next

section, “Setting the Fresh Air Reading”.

Setting the Fresh Air Reading

CAUTION: If you suspect the monitoring environment is not a fresh air env i ronm ent, use the

zero air calibration cylinder to introduce “fresh air” to the detector and verify an
accurate fresh air reading.

1. Verify that the o x ygen detector is in a fresh air environment (environment known to

2. Verify a reading of 20.9% oxygen at the controller.

3. Perform a fresh air adjustment operation at the controller. See the controller

Maintenance

This section describes maintenance procedures. It includes preventive maintenance,
troubleshooting, and component replacement procedures.

Preventive Maintenance

This section describes a preventive maintenance schedule to ensure the optimum
performance of the oxygen detector. It includes daily, monthly, and quarterly procedures.

Daily

Verify a display reading of 20.9% oxygen at the controller. Investigate significant changes
in the display reading.

Monthly

This procedure describes a test to verify that the oxygen detector responds properly to
oxygen deficiency.

be free of toxic and combustible gases, and of normal oxygen content, 20.9%).

If the display reading is 20.9% oxygen, start up is complete. The oxyg en d e tector is in
normal operation. If the display reading is not 20.9% oxygen, continue with step 3.

operator’s manual for instructions.

6 • 65-2494RK/65-2497RK Oxygen Detect or

WARNING: The controller is not an active gas monitoring device during the response

test procedure.

NOTE: Performing a respon se test on the oxygen dete ctor may cause alarms. Be sure to

put the controller into its calibration program or disable external alarms before
performing this test.

1. Place the controller into its calibration program or disable external alarms.

2. Verify tha t the controller display reading is 20.9% oxygen.
If the display reading is not 20.9% oxygen, set the fresh air reading, then continue this

procedure. See the controller operator’s manual for instructions to set the fresh air
reading.

3. Exhale into the bottom of th e oxygen detector housing.

4. Stop exhaling into the bottom of the detector, then verify that the reading on the
controller display decreased from the normal reading of 20.9% oxygen.

NOTE: If the reading does not decrease, calibrate the detector as described in

“Calibrati on” on page 11.

5. When the display reading rises above the decreasing alarm setpoint, return the
controller to normal operation.

Quarterly

Calibrate the detector as described in “Calibration” on page 11. See the calibration
frequency discussion in “Calibration Frequency” on page 10 to determine if a quarterly
calibration schedule fits your needs.

65-2494RK/65-2497RK Oxygen Det e ct or • 7

Troubleshooting

The troubleshooting guide describes symptoms, probable causes, and reco mmended
action for problems you may encounter with the oxygen detector.

NOTE: This troubleshooting guide describes detector problems only. See the controller

operator’s manual for problems you may encounte r with the controller.

Table 2: Tr oubleshooting the Oxygen Detector

Condition Symptom(s) Probable Causes Recommended Action

Fail Condition • Controller indicates a

Slow or No
Response/
Difficult or
Unable to
Calibrate

fail condition.

• Detector responds
slowly or does not
respond to response
test.

• Unable to accurately
set the fresh air or
zero reading during
calibration.

• Detector requires
frequent calibration.

Note: Under “normal”
circumstances, the
transmitter requires
calibration once every 3
months.

Some applications
may require a more
frequent calibration
schedule.

• The detector wiring is
disconnected or
misconnected.

• The plug-in sensor is
not properly plugged
into the socket pattern
in the detector ho using
body.

• The detector’s zero
reading is low enough
to cause a fail
condition.

• The detector is
malfunctioning.

• The calibration cylinder
is low, out-dated, or
defective.

• The calibration gas is
not an appr opriate
concentration.

• The membrane on the
detector housing cap is
blocked with dirt or
some other particulate
contamination.

• The detector is
malfunctioning.

1. Verify that the detector wiring is
correct and secure.

2. Confirm that the plug-in sensor is
installed properl y.

3. Perform a fresh air adjustment. A full
calibration is recommended.

4. If the fail condition continues, replace
the plug-in sensor as described later
in this section.

5. If the fail condition continues, contact
RKI for further instruction.

1. Verify that the calibration cylinder
contains an adequate supply of a
fresh test sample.

2. Verify that the calibration gas
concentration is appropriate for the
transmitter. Zero emission air (20.9%
oxygen) is normally used for a fresh
air adjustment if the environment is
suspect and 100% nitrogen (0%
oxygen) is normally used for a zero
adjustment.

3. Check the sensor face for dirt. Clean
if necessary.

4. Check the face of the detector
housing cap and remove any
particulate contamination from the
hydrophobic membrane if necessary.
If the membrane appears saturated
with contamination or damaged,
replace the membrane as described
in the next section.

5. If the calibration/response difficulties
continue, replace the plug-in sensor
as described later in this section.

6. If the calibration/response difficulties
continue, contact RKI for further
instruction.

8 • 65-2494RK/65-2497RK Oxygen Detect or

Replacing Components of the Oxygen Detector

This section includes a procedure to replace the plug-in oxygen sensor, one to replace the
hydrophobic membrane, and one to replace the entire oxygen detector assembly. In most
cases, it is not necessary to replace the entire detector assembly.

Replacing the Plug-in Oxygen Sensor

CAUTION: The plug-in sensor contains electrolyte which is an irritant. Do not disassemble the

sensor when replacing it with a new one. If sensor electrolyte comes in contact with
your skin, wash affected area thoroughly with soap and water.

1. Turn off the controller.

2. Turn off or unplug p ower to the controller.

3. Unscrew the detector housing cap from the detector housing body.

4. Unplug and remove the old oxygen sensor.

5. Carefully plug the replacement sensor into the sockets located in the detector housing
body.

6. Make sure the cap gasket is in place and screw the detector housing cap back onto the
detector housing body.

7. Tu rn on power to the controller.

8. Turn on the controller and place into normal operation.

CAUTION: Allow the replacem ent sens or to warm up for 5 minutes before you continue with the

next step.

9. Calibrate the detector as described in “Calibration” on page 11.

Replacing the Hydrophobic Membrane

1. Turn off the controller.

2. Turn off or unplug incoming power to the controller.

3. Unscrew the detector housing cap from the detector housing body.

4. Gently pry up the edge of the white hydrophobic mem b rane with a small flat blade
screwdriver or a similar tool.

5. Peel off the hydrophobic membrane. It may be necessary to clean off the detector
housing cap face to remove any residue left from the adhesive backed membrane.

6. Install the new membrane in t he recess on the face of the detector housing cap.

7. Make sure the cap gasket is in place and screw the detector housing cap back onto the
detector housing body.

8. Tu rn on the power to the controller.

9. Turn on the controller.

65-2494RK/65-2497RK Oxygen Det e ct or • 9

Replacing the Oxygen Detector

NOTE: In most cases, it is only necessary to replace the plug-in sensor.

1. Turn off the controller.

2. Turn off or unplug incoming power to the controller.

3. If the detector is installed directly on a controller, open the controller door.
If the detector is installed remotely from a controller in a junction box, remove the

junction box cove r.

4. If the detector is installed directly on a controller, disconnect the detector leads from
the detector terminal strip in the controller. Note the position of the color-coded leads
as you remove them.

If the detector is installed remotely from a controller in a junction box, disconnect the
detector leads from the terminal block in the junction box. Note the position of the
color-coded leads as you remove them.

5. Unscrew the detector from the controller conduit hub or junction box conduit hub.

6. Gu ide the detector leads of the replacement detector through the controller conduit
hub or junction box conduit hub, then screw the mounting threads of the detector into
the hub. If necessary for environmental conditions, apply thread sealant or teflon tape
to the hub and/or detector threads to seal them.

7. If the detector is installed directly on a controller, connect the detector leads to the
appropriate detector terminal strip terminals. See Figure 4 on page 5 for wiring to a
generic controller. See the controller operator’s manual and the controller’s detector
head specification sheet for the 65-2494RK detecto r for wiring specific to your
controller.

If the detector is installed remotely from a controller in a junction box, connect the
detector leads to the terminal block the same way the old detector was wired (see
Figure 4 on page 5). See the controller operator’s manual and the controller’s detector
head specification sheet for the 65-2497RK detector to verify the connections to the
controller are correct.

8. If the detector is installed remotely from a controller in a junction box, reinstall the
junction box cove r.

9. Turn on or plug in power to the controller.

10. Turn on the controller and place into normal operation.

CAUTION: Allow the replacement detector to warm up for 5 minutes before y o u c o ntinue with

the next step.

11. Calibrate the replacement detector as described in “Calibration” on page 11.

Calibration Frequency

Although there is no particular calibration frequency that is correct for all applications, a
calibration frequency of every 3 months is adequate for most oxygen detector
applications. Unless experience in a particular application dictates otherwise, RKI
Instruments, Inc. recommends a calibration frequency of every 3 months for the oxygen
detector.

10 • 65-2494RK/65-2497RK Oxygen Detector

Calibration

If an application is not very demanding, for example detection in a clean, temperature
controlled environment, and calibration adjustments a re minima l at calibration, then a
calibration frequency of every 6 months is adequate.

If an application is very demanding, for example if the environment is not well controlled,
then more frequent calibration than every 3 months may be necessary.

This section describes how to calibrate the oxygen detector. It includes procedures to
prepare for calibration, set the fr esh air r eading, set the zero r eading, and return to normal
operation. It describes calibration using a calibration kit that includes a calibration cup,
calibration gas, sample tubing, and a fixed flow regulator with an on/off knob. RKI
Instruments, Inc. recommends using a 0.5 LPM (liters per minute) fixed flow regulator.

Prepari ng for Ca libration

1. Screw the calibration cup onto the bottom of the oxygen detector.

2. Screw the regulator into the zero air calibration cylinder. Make sure the regulator is
off. It is off when the on/off knob is turned all the way clockwise.

3. Use the sample tubing to connect the regulator to the calibration cup.

NOTE: If you can verify that the oxygen detector is in a fresh air environment, you do

not need to apply zero air to the detector before adjusting the fresh air reading.

4. Put the controller into its calibration program. See the controller operator’s manual
for instructions to enter the calibration program.

Setting the Fresh Air Reading

1. Follow the instructions in the controller operator’s manual for setting the fresh air
reading.

2. When the instructions call for applying z e ro air to the detector, turn the regulator’s
on/off knob counterclockwise to open it. Gas will begin to flow.

3. Allow the gas to flow for two minutes.

4. Set the fresh air reading according to the controller operator’s manual.

5. Turn the regulator’s on/off knob clockwise to close it.

6. Unscrew the regulator from the zero air calibration cylinder. Leave the sample tubing
connected to the regulator and the calibration cup.

NOTE: Depending on the size of your zero air cylinder, it is possible that you will have a

different regulator for the zero air cylinder and the nitrogen gas cylinder. If
necessary to fit the nitrogen gas cylinder, change the regulator.

Setting the Zero Reading

1. Screw the regulator into the 100% nitrogen calibration cylinder. Make sure the
regulator is off. It is off when the on/off knob is turned all the way clockwise.

2. Follow the directions in the controller operator’s manual for setting the zero reading.

3. When the directions call for exposing the detector to gas, turn the regulator’s on/off
knob counterclockwise to open it. Gas will begin to flow.

65-2494RK /65-2 497R K Oxygen D ete ctor • 11

4. Allow the gas to flow to the detector for 2 minutes.

5. Set the zero reading according to the controller operator’s manual.

6. After setting the zero reading, turn the regulator’s on/off knob clockwise to turn it
off.

7. Unscrew the regulator from the cylinder.

8. Unscrew the calibration cup from the oxygen detector. Make sure that you do not
loosen the detector housing cap when you unscrew the calibration cup.

NOTE: For convenience, leave the regulator and calibration cup connected by the

sample tubing.

9. Allow about 45 seconds for the gas reading to increase above the decreasing alarm
point and then return the controller to normal operation.

NOTE: If you do not allow the gas reading to increase above the decreasing alarm point,

then unwanted alarms may occur.

10. Verify tha t the controller display reading increases and stabilizes at 20.9% oxygen.

11. Store the components of the calibration kit in a safe and convenient place.

12 • 65-2494RK/65-2497RK Oxygen Detector

Parts List

Table 3 lists replacement parts and accessories for the oxygen detector.

Table 3: Parts List

Part Number Description

06-1248RK-03 3 foot length of sample tubing for the calibration kit
07-0039RK Detector housing cap gasket
18-0400RK-01 Junction box with rubber spacers
65-1025RK Oxygen plug-in sensor
65-2494RK Oxyge n replacement detector assembly (includ e s sensor)
71-0179RK 65-2494RK/65-2497RK Oxygen Detector Operator’s Manual (this docu-

ment)
81-0076RK Zero air calibration cylinder, 17 liter steel
81-0076RK-01 Zero air calibration cylinder, 34 liter steel
81-0076RK-03 Z ero air calibration cylinder, 103 liter steel
81-0078RK 100% nitrogen calibration cylinder, 17 liter steel
81-0078RK-01 100% nitrogen calibration cylinder, 34 liter steel
81-0078RK-03 100% nitrogen calibration cylinder, 103 liter steel
81-F301RK Calibration kit for oxygen detector head, 103 liter
81-F301RK-LV Calibration kit for oxygen detector head, 34 liter
81-1050RK Regulator with gauge and knob, 0.5 LPM, for 17 liter and 34 liter steel

calibration cylinders
81-1051RK Regulator with gauge and knob, 0.5 LPM, for 34AL/58/103 liter cali-

bration cylinders
81-1117RK Calibration cup

65-2494RK /65-2 497R K Oxygen D ete ctor • 13