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.