RKI Instruments 35-3010RKA-04H User manual

RKI Instruments, Inc.
www.rkiinstruments.com
35-3010RKA-04H Sample-Draw
Detector Head
Operator’s Manual
Part Number: 71-0605
Revision: P1
Released: 8/16/22

2• 35-3010RKA-04H Sample-Draw Detector Head Operator’s Manual
WARNING
Read and understand this instruction manual before operating
detector. Improper use of the detector 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. For most applications,
typical calibration frequencies are between 3 and 6 months but can be
more often or less often based on your usage.

35-3010RKA-04H Sample-Draw Detector Head Operator’s Manual • 3
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 from date of shipment from
RKI Instruments, Inc. Any parts found defective within that 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 service, and which must be cleaned, repaired, or
replaced on a routine basis. Examples of such items are:
• Absorbent cartridges
•Fuses
• Pump diaphragms and valves
•Batteries
• Filter elements
Warranty 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, and we are not responsible for removal or replacement costs, local repair costs,
transportation costs, or contingent expenses incurred without our prior approval.
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 APARTICULAR PURPOSE. INNO
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 not assume indemnification for any accident or damage caused by the operation of this gas
monitor, and our warranty is limited to the replacement of parts or our complete goods.

4• 35-3010RKA-04H Sample-Draw Detector Head Operator’s Manual
Table of Contents
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Housing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Flow System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Detection System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Mounting the Sample-Draw Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Connecting the Sample Lines to the Sample-Draw Detector . . . . . . . . . . . . . . . . . . . . . . 17
Wiring the Sample-Draw Detector to a Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Low Flow Alarm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Replacing Components of the Sample-Draw Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Adjusting the Low Flow Setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Calibration Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Calibration, Hydrogen Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Preparing for Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Setting the Response Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

35-3010RKA-04H Sample-Draw Detector Head Operator’s Manual • 5
Returning to Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Calibration, Oxygen Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Preparing for Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Setting the Fresh Air Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Returning to Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

6• Overview 35-3010RKA-04H Sample-Draw Detector Head
Overview
This manual describes the 35-3010RKA-04H sample-draw detector. This manual also describes
how to install, start up, maintain, and calibrate the detector. A parts list at the end of this manual
lists replacement parts and accessories for the sample-draw detector.
Specifications
Table 1 lists specifications for the 35-3010RKA-04H.
WARNING: When using the 35-3010RKA-04H, you must follow the instructions and
warnings in this manual to assure proper and safe operation of the
35-3010RKA-04H and to minimize the risk of personal injury. Be sure to
maintain and periodically calibrate the 35-3010RKA-04H as described in this
manual.
Table 1: Specifications
Target Gases & Detection Ranges Hydrogen (H2): 0 - 100% LEL
Oxygen (O2): 0 - 25% volume
Input Power 24 VDC
Current Draw 275 mA
Output Signals 4-20 mA each channel
Construction (housing) Fiberglass/polyester (NEMA 4X)
Dimensions 15.44 in. H x 12.55 in. W x 8.31 in. D
Weight 14 lbs.
Sampling Method Sample-draw
Sample Flow 1.2 SCFH (nominal)
Response Time 90% in 30 seconds
Accuracy
Hydrogen:
± 5% of reading or ± 2% LEL (whichever is greater)
Oxygen:
± 0.5% O2

35-3010RKA-04H Sample-Draw Detector Head Description • 7
Description
This section describes the components of the 35-3010RKA-04H sample-draw detector. The
sample-draw detector consists of the housing, flow system, and detection system.
Figure 1: Sample-Draw Detector Component Location
Housing
The sample-draw detector’s fiberglass housing is weather- and corrosion-resistant. It is suitable
for installation where general purpose equipment is in use. The housing door is hinged on the left
side and is secured by two latches on the right side.
Four mounting feet are attached to the back of the housing (one at each corner). Use the mounting
feet to install the housing to a vertical surface. Use the two conduit hubs on the bottom of the
housing to make wiring connections.
4/20
ZER O
SPAN
BKRD
OXY
TP -
BATT
+
W
FB
TOXIC
TOXIC
Flow
Block
Amp 1
TP +
OXY
G
+
24V
Hydrophobic
Filter (AcroPak)
Oxygen Sensor
Pump
Preamp
Circuit
Board
H2S Sensor
Dummy Plug
LEL Transmitter
Charcoal Filter
Inlet Fitting For 1/4" OD
Rigid Tubing
3/4 Conduit Hub, 2X
Exhaust Fitting For 1/4"
OD Rigid Tubing
Hydrogen Sensor
CO Dummy Plug
Amp 2
Oxygen Transmitter
Main CircuitBoard
Reset Switch

8• Description 35-3010RKA-04H Sample-Draw Detector Head
An aluminum subpanel is mounted to the interior of the housing. The sample-draw detector’s
internal components are mounted to the subpanel.
Flow System
The sample-draw detector’s flow system consists of the INLET fitting, hydrophobic filter,
charcoal filter, pump, flowmeter, bypass valve, status lights, pressure switch, flow block, and
EXHAUST fitting (see Figure 1). Figure 2 illustrates how the gas sample moves through the flow
system.
Figure 2: Sample-Draw Detector Flow Diagram
Oxygen
Charcoal
Filter
CO
Pressure Switch
Flow meter
Bypass
Valve
Flow Block
H2S
H2
Pump
Exhaust
Inlet Hydrophobic
Filter

35-3010RKA-04H Sample-Draw Detector Head Description • 9
INLET Fitting
The INLET fitting on the bottom of the housing allows the gas sample to enter the sample-draw
detector. The INLET fitting accepts 1/4 in. rigid tubing. See “Installation” on page 16 for
instructions to connect tubing to the INLET fitting.
Hydrophobic Filter
The hydrophobic filter is to the left of the main circuit board. It is held in place by a metal clip. It
prevents water and other liquids from contaminating the flow system. Replace the filter when it
appears dirty, discolored, or clogged. If a liquid other than water is drawn into the filter, replace
the filter as soon as possible.
Charcoal Filter
The charcoal filter is located above the LEL transmitter. It is held in place by a metal clip. The
charcoal filter is placed after the H2S sensor and before the CO sensor in the flow system. It
scrubs out interfering gases which may cause the CO sensor to respond, such as H2S or certain
hydrocarbons. Replace the charcoal filter when false high CO readings are noticed, especially in
the presence of H2S. It is included in this version of the sample draw detector in case a CO sensor
is added in the field. If a CO sensor is added in the field, a new charcoal filter should also be
installed.
Pump
The pump is located to the left of the main circuit board near the bottom left of the sample-draw
detector. The pump pulls the gas sample into the sample-draw detector. The pump operates on 24
VAC, which is generated from the 24 VDC supplied to the sample draw detector.
Flowmeter
The flowmeter is attached to the main circuit board near the top left corner (see Figure 5). A ball
in the flowmeter column indicates the flow rate to the sensors. The flowmeter measures the flow
in the range 0.2 to 2.0 SCFH (Standard Cubic Feet per Hour). Although the sample-draw detector
will operate down to a flow of 0.6 SCFH, the optimum flow rate is 1.2 SCFH.
Bypass Valve
The bypass valve is to the left of the flowmeter. The bypass valve adjusts the flow rate to the
sensors. Use a flat-blade screwdriver to adjust the bypass valve.
NOTE: The bypass valve allows fine adjustments of the flow rate. For a wider range of
adjustment, use the flow adjust potentiometer (see Figure 5).
Status Lights
Two status lights are above the flowmeter.
Pilot Light
The green Pilot light is on when the sample-draw detector is receiving power.

10 • Description 35-3010RKA-04H Sample-Draw Detector Head
Fail Light
The red Fail light is on when the sample flow rate is below the low flow level.
NOTE: The factory set low flow level is 0.6 SCFH (±0.2). See “Adjusting the Low Flow
Setting” on page 25 for instructions to adjust this setting.
Pressure Switch
The pressure switch is mounted to the opposite side of the main circuit board. The pressure switch
monitors the flow rate to the sensors.
If the flow rate falls below the preset low flow level, the pressure switch causes the fail relay to
interrupt the sensor signal from the hydrogen and oxygen channels and the signal in the 4-20 mA
line for the CO and H2S channels. This causes a downscale reading at the monitor on these
channel. The low flow level is factory-set at 0.6 SCFH (±0.2 SCFH).
NOTE: There is no low flow indication for the hydrogen or oxygen channel in the 35-
3010RKA-04H.
Flow Block
The flow block is located in the lower right corner of the sample-draw detector. All the sensors are
installed in the flow block. The flow block routes the sampled air to each sensor.
EXHAUST Fitting
The EXHAUST fitting on the bottom of the housing allows the gas sample to exit the sample-
draw detector. The EXHAUST fitting accepts 1/4 in. rigid tubing. See “Installation” on page 16
for instructions to connect tubing to the EXHAUST fitting.
Detection System
The detection system consists of the gas sensors, LEL and oxygen transmitters, preamp circuit
board, and the main circuit board.
Hydrogen Sensor
The hydrogen sensor is installed in the lower left of the flow block. The hydrogen sensor includes
the sensing elements, flame arrestor, connector, and sensor leads.
Sensing Elements
Two sensing elements are protected within the sensor assembly. Through a series of thermal and
electronic reactions, these elements produce an output that is proportional to the detection range
of the sample draw detector. The LEL transmitter converts the output to a 4 - 20 mA signal which
can be used by a recording or monitoring device.
The porous flame arrestor allows the gas sample to enter the sensor assembly and contact the
sensing element. The flame arrestor also contains sparks within the sensor.The sensor has a built-
in molecular sieve that only allows hydrogen to diffuse into the detector.

35-3010RKA-04H Sample-Draw Detector Head Description • 11
Connector
The top of the sensor includes five pins that plug into the socket connector. This connector allows
you to replace the sensor without disconnecting the wiring. The sensor leads are soldered to the
connector.
Sensor Leads
Four color-coded leads extend from the connector. The leads allow you to connect the hydrogen
sensor to the main circuit board.
Oxygen Sensor
The oxygen sensor is installed in the lower right of the flow block. The oxygen sensor includes
the oxygen cell, connector, and sensor leads.
Oxygen Cell
The oxygen cell is protected within the sensor assembly. Through a series of chemical and
electronic reactions, the cell produces a millivolt output that is proportional to the detection range
of the sample-draw detector. The oxygen transmitter converts the output to a 4 - 20 mA signal
which can be used by a recording or monitoring device.
Connector
The cable that extends from the sensor terminates in a socket that plugs into a matching 7-pin
male connector. The socket and connector allow you to replace the sensor without disconnecting
the wiring. The sensor leads are soldered to the male connector.
Sensor Leads
Two color-coded leads extend from the connector. The leads allow you to connect the oxygen
sensor to the main circuit board.
Carbon Monoxide Sensor
The carbon monoxide gas sensor position is located in the upper left side of the flow block. In the
35-3010RKA-04H, the carbon monoxide sensor position in the flow block is occupied by a
dummy sensor.
Hydrogen Sulfide Gas Sensor
The hydrogen sulfide gas sensor position is located in the upper right side of the flow block. In the
35-3010RKA-04H, the hydrogen sulfide gas sensor position in the flow block is occupied by a
dummy sensor.

12 • Description 35-3010RKA-04H Sample-Draw Detector Head
LEL Transmitter
The LEL transmitter is mounted to the left of the oxygen transmitter and above the main circuit
board. It consists of the span pot, zero pot, one internally wired terminal strip, and the test points.
Figure 3: LEL Transmitter
Span/Zero Pots
The span and zero pots are located at the bottom edge of the transmitter and are used for
calibration. Use the span pot to make adjustments to gas response readings and the zero pot to
make adjustments to the zero reading.
Transmitter Interconnect Terminal Strip
The transmitter interconnect terminal strip is the seven-point terminal strip near the right edge of
the transmitter. The transmitter is factory wired to the sensor and main circuit board.
Test Points
The test points are located on the left side of the transmitter and are labeled TP+ and TP-. A 100
mV - 500 mV output is available at these test points for use during calibration.
LEL Transmitter
Zero Pot
Interconnect
Terminal Strip
Test Point TP+
Span PotTest Point TP-

35-3010RKA-04H Sample-Draw Detector Head Description • 13
Oxygen Transmitter
The oxygen transmitter is mounted to the right of the LEL transmitter and above the main circuit
board. The amplifier includes the amplifier type selector, two internally wired terminal strips,
span pot, zero pot, and test points.
Figure 4: Oxygen Transmitter
Transmitter Type Selector
The transmitter type selector is near the bottom left corner of the amplifier. It is to the left of the
detector terminal strip and below the span pot.
The transmitter included with the sample-draw detector is designed for use with RKI’s oxygen
and toxic gas sensors. The transmitter type selector determines for which sensor the amplifier is
intended. For oxygen transmitters, a jumper block is installed over the OXY selector.
Detector Terminal Strip
The detector terminal strip is the four-point terminal strip near the bottom edge of the transmitter.
It is factory wired to the transmitter.
Interconnect Terminal Strip
The interconnect terminal strip is the four-point terminal strip near the top edge of the transmitter.
It is factory wired to the main circuit board.
Span/Zero Pots
The span and zero pots are located on the left side of the transmitter and are used for calibration.
Use the span pot to make adjustments to gas response readings and the zero pot to make
adjustments to the zero reading.
Test Points
The test points are located on the top of the transmitter on either side of the transmitter
interconnect terminal strip. They are labeled TP+ and TP-. A 100 mV - 500 mV output is
available at these test points for use during calibration.
FB
Oxygen
Transmitter
24V4/20
TP -
TP +
BATT
+
OXY
+
OXY
WBK
ZERO
RD
Test Point TP+
Transmitter Type Selector,
Set To OXY Interconnect
Terminal Strip
Span Pot
Zero Pot
Sensor Terminal
Strip
Test Point TP-
TOXIC
SPAN
G
TOXIC

14 • Description 35-3010RKA-04H Sample-Draw Detector Head
Preamp Circuit Board
The preamp circuit is used to connect the CO and H2S sensors to the main circuit board and to
secure the sensors in the flow block. Two cables mate to the main circuit board: the one on the left
is for the CO sensor signal and the one of the right is for the H2S sensor signal. Since both the CO
and H2S sensors are replaced with a dummy plug in the 35-3010RKA-04H the CO and H2S
sensor signal cables carry no signal in this version of the 35-3010RK.
Main Circuit Board
Figure 5: Main Circuit Board
The main circuit board includes the interconnect terminal strip, sensor/transmitter terminal strip,
amp 1 circuit, amp 2 circuit, pump terminal strip, relay, and reset switch.
NOTE: The flowmeter and status lights are mounted to the main circuit board but are
considered part of the flow system.
Interconnect Terminal Strip
The interconnect terminal strip is the sixteen-point terminal strip near the bottom edge of the main
circuit board. Use the interconnect terminal strip to connect the sample-draw detector to power
and an external device.
Test Point CAL + 2
Amp 1
(CO)
Zero Span Zero
Fail LED
Sensor/Transmitter
Terminal Strip
Pressure Switch
Reset
Switch
Pilot LED
Amp 2
(H2S)
Span
Test Point CAL + 1
Test Point CAL -2
Test Point CAL - 1
AC Terminal
Strip Not Used
Interconnect Terminal
Strip
Low Flow Adjust
Flow Adjust Pot
Flowmeter
Pump Terminal Stip
Relay

35-3010RKA-04H Sample-Draw Detector Head Description • 15
Sensor/Transmitter Terminal Strip
The sensor/transmitter terminal strip is the sixteen-point terminal strip near the right edge of the
circuit board. Use the transmitter terminal strip to connect sensors or transmitters to the main
circuit board.
NOTE: The sensors and transmitters are factory wired to the sensor/transmitter terminal strip.
See “Wiring the Sample-Draw Detector” on page 17 for all wiring procedures related to
the sample-draw detector.
Amp 1 and Amp 2 Circuits
These circuits are located to the left of the sensor/transmitter terminal strip. They each include test
points, a zero pot, and a span pot. Amp 1 is on the left and is for the CO channel. Amp 2 is on the
right and is for the H2S channel.
The zero and span pots are used during calibration. Use the span pot to make adjustments to gas
response readings and the zero pot to make adjustments to the zero reading.
The test points are labeled CAL-1 and CAL+1 for the CO channel and CAL-2 and CAL+2 for
the H2S channel. No output is available at either set of test points.
Pump Terminal Strip
The pump terminal strip is the four-point terminal in the top left corner of the circuit board. Use
the pump terminal strip to connect the pump and pressure switch to the main circuit board.
NOTE: The pump and pressure switch are factory-wired to the circuit board. See “Wiring the
Sample-Draw Detector” on page 17 for all wiring procedures related to the sample-draw
detector.
Relay
The relay is approximately in the middle of the circuit board. The relay is a four pole, double-
throw (4PDT) relay and is rated for 2 amps at 25 VDC (resistive). If the pressure switch senses a
low flow condition, the relay interrupts the sensor signal from the direct connect hydrogen and
oxygen channels and the 4-20 mA signal from the CO and H2S channels which will cause a
downscale reading at the controller or recording device.
NOTE: There is no flow fail indication for the hydrogen and oxygen channels on the
35-3010RKA-04H Sample Draw Adapter.
Reset Switch
A small reset button is located in the upper left corner of the main PCB. When a low flow
condition occurs, the pump will be shut off. To reset the low flow condition and start the pump
again, press and hold the reset switch for about 2 seconds, then release.

16 • Installation 35-3010RKA-04H Sample-Draw Detector Head
Installation
This section describes procedures to mount the sample-draw gas detector in the monitoring
environment and wire the sample-draw detector to power and an external device.
Mounting the Sample-Draw Detector
1. Select the mounting site. Consider the following when you select the mounting site.
• Is there enough room to open the housing door and make wiring connections at the bottom
of the housing and tubing connections at the right of the housing?
• Make sure there is sufficient room to perform start-up, maintenance, and calibration
procedures.
Figure 6: Mounting the Sample-Draw Detector
2. Close and latch the housing door.
NOTE: The sample-draw detector is shipped with the mounting feet “tucked under”
the housing to protect the mounting feet during shipment.
3. Slightly loosen the screw that secures one of the mounting feet to the housing, then rotate the
mounting foot 180 degrees.
Ø .31 x .50 slot, 4X
8.31
.18
Tube Fitting for 1/4"
OD tube, 2X
3/4" Conduit Hub, 2X
10.00
12.55
Door Latch
15.44
14.94
14.55

35-3010RKA-04H Sample-Draw Detector Head Installation • 17
4. Tighten the screw that secures the mounting foot to the housing.
5. Repeat steps 3 and 4 for the remaining three mounting feet.
6. Position the sample-draw housing on a vertical surface at eye level (4 1/2 to 5 feet from the
floor).
7. Insert 1/4 in. or 5/16 in. screws through the slots in the mounting feet to secure the housing to
the mounting surface.
Connecting the Sample Lines to the Sample-Draw
Detector
1. Attach 1/4 in. O.D. rigid polypropylene or rigid Teflon sample tubing to the INLET fitting.
CAUTION: If you use flexible sample tubing (polyurethane is acceptable), use an
appropriate insert to seal the connection between the tubing and the
INLET fitting.
2. Place the opposite end of the tubing at the sampling area.
CAUTION: Avoid loops or slumps in the incoming sample line. To reduce response
time, keep the incoming sample line as short as possible.
3. Attach rigid sample tubing to the EXHAUST fitting.
4. Route the opposite end of the tubing to an open area where the sample can safely disperse.
Wiring the Sample-Draw Detector
WARNING: Always verify that the power source is OFF before you make wiring connections.
1. Turn off the controller.
2. Turn off or unplug incoming power to the controller.
3. Unlatch and open the housing door of the sample-draw detector.
4. Guide a six-conductor 18 gauge, shielded cable or six 18 gauge wires in conduit through one
of the conduit hubs at the bottom of the sample-draw housing. If necessary, use both hubs to
bring the wires in making sure that all the wires for a particular channel go through the same
hub.
5. Connect the cable to the sample-draw detector’s interconnect terminal strip as shown in
Figure 7.

18 • Installation 35-3010RKA-04H Sample-Draw Detector Head
6. Close and latch the housing door of the sample-draw detector.
CAUTION: Leave the cable shield drain wire insulated and disconnected at the
sample-draw detector. You will connect the opposite end of the drain
wire at the controller.
7. Route the cable or wires in conduit leading from the sample-draw detector to the controller.
8. Connect the drain wire to an available chassis ground at the controller. RKI controllers
typically have a ground stud that can be used to ground the cable’s drain wire.
Figure 7: External (Field) Wiring, Sample-Draw Detector
LEL
(Controller Transmitter
Terminals)
24 VDC
4/20 (Feedback)
+
Interconnect Terminal Strip
Oxygen
(Controller Trasnmitter
Terminals) +
24 VDC
4/20 (Feedback)
Reset Switch
Sample Draw Housing
Main Circuit Board

35-3010RKA-04H Sample-Draw Detector Head Installation • 19
Figure 8: Internal (Factory) Wiring, Sample-Draw Detector
TOXIC
SPAN
ZERO
G
OXY
BK WRD
OXY TOXIC
24V4/20
+ +
FB
TP -
BATT
TP +
CO
(Not
Used)
H2S
(Not
Used)
Pump
Factory
Wired
Pressure Switch
Factory Wired
White
Red
Green
LEL Sensor
Connector
LEL
Detector
Black
Oxygen Sensor
Green
White
IN STR UMENTS
SENSOR
GRN
TP-
BLK
SP AN Z ER O
POWER/SIG
P/N 57 -1 05 0R K
REV. 0
TP+
GND
24V
4-20
RED
WHT

20 • Start Up 35-3010RKA-04H Sample-Draw Detector Head
Start Up
This section describes procedures to start up the sample-draw detector and place the sample-draw
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. See controller operator’s
manual.
3. Turn on or plug in the incoming power at the controller, then turn on the controller.
4. Verify that the controller is on and operating properly.
5. Verify that the Pilot light is on at the sample draw detector.
6. Verify that the flowmeter indicates a flow rate of approximately 1.2 SCFH. If necessary, use
the bypass valve or flow adjust potentiometer to adjust the flow rate.
NOTE: The following step tests for leaks in the sample line. This test may cause a
low flow condition at the sample-draw detector.
7. Verify that the incoming sample line is not leaking. To test the sample line, plug the open end
of the sample line with your thumb. If the flowmeter ball drops to the bottom of the
flowmeter, the incoming sample line is not leaking.
8. Remove your thumb from the sample line, press the pump reset switch, and verify the
flowmeter returns to a normal flow rate.
Setting the Zero Reading
CAUTION: If you suspect the presence of hydrogen, carbon monoxide, or an abnormal oxygen
condition (not 20.9%) in the monitoring environment, use the calibration kit and the
zero air calibration cylinder to introduce “fresh air” to the sample draw adapter
and verify an accurate zero setting.
1. Verify that the sample-draw detector is sampling a fresh air environment (environment known
to be free of hydrogen and of normal oxygen content, 20.9%).
2. Open the housing door.
3. Set a voltmeter to measure in the millivolt (mV) range.