RKI Instruments 35-3000RK-LEL User Manual

35-3000RK-LEL

Combustible Gas Sample-Draw Detector

Operator’s Manual

Part Number: 71-0104RK

vision: P1

Re
Released: 9/18/04

RKI Instruments Inc.

33248 Central Ave.

Union City, CA 94587

PH: 800-754-5165 Fax: [phone]

www.rkiinstruments.com

Product W arranty

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:

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

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 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 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.

2 • 35-3000RK-LEL Combustible Gas Sample-Draw Detector

Table of Contents

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Flow System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Detection System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Mounting the Combustible Gas Sample-Draw Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Connecting the Sample Lines to the Sample-Draw Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Wiring the Combustible Gas Sample-Draw Detector to a Controller. . . . . . . . . . . . . . . . . . . . . . . . . 10

Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Introducing Incoming Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Setting the Fresh Air Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Replacing Components of the Combustible Gas Sample-Draw Detector . . . . . . . . . . . . . . . . . . . . . 16

Adjusting the Low Flow Setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Assembling the Calibration Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Setting the Fresh Air Reading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Setting the Zero Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

35-3000RK-LEL Combustilbe Gas Sample-Draw Detector • 3

Overview

This operator’s manual describes the combustible gas sample-draw detector . This manual
also describes how to install, start up, maintain, and calibrate the sample-draw detector
when using it with a gas monitoring controller. 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 combustible gas sample-draw detector. See the controller
Operator’s Manual for information specific to the controller.

Target Gas Combustible gas, methane calibration standard
Input Power 24 VDC Nominal (23 VDC - 28 VDC)

Table 1: Specifications

Construction (housing) Fiberglass/polyester (NEMA 4X)
Dimensions 8.5 in. H x 6.5 in. W x 4.25 in. D
Weight 4.5 lbs.
Sampling Method Sample-draw
Sample Flow 1.5 SCFH (nominal)
Detection Range

Response Time 90% in 30 seconds
Linearity ±5% of detection range
Repeatability ±2% of detection range

0 to 100% LEL

1

4 • 35-3000RK-LEL Combustible Gas Sample-Draw Detector

Description

This section describes the components of the combustible gas sample-draw detector. The
sample-draw detector consists of the housing, flow system, and detection system.

Flow Adjust

Potentiometer

Pump/Pressure Switch

Terminal Block

Fail LED

Pilot LED

Flowmeter

Bypass valve

Hydrophobic

Filter

Mounting
Foot, 4X

Low FlowPotentiometer

Detector
Terminal Strip

Exhaust
Fitting

Inlet
Fitting

Relay

Interconnect
Terminal Strip

Oxygen Detector
(Not Used in This
Version)

CombustibleGas
Detector

3/4" Conduit Hub, 2X

Figure 1: Combustible Gas Detector Sample-draw 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.
The flowmeter and status lights are visible through a window in the housing door.

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 to a gas monitoring controller.

An aluminum subpanel is mounted to the interior of the housing. The sample-draw
detector’s internal components are mounted to the subpanel.

35-3000RK-LEL Combustilbe Gas Sample-Draw Detector • 5

Flow System

The sample-draw detector’s flow system consists of the INLET fitting, hydrophobic filter,
pump, flowmeter, bypass valve, status lights, pressure switch, and EXHAUST fitting (see
Figure 1). Figure 2 illustrates how the gas sample moves through the flow system.

Exhaust

Bypass

Valve

Flowmeter

Inlet Filter Pump Sensor

Pressure Switch

To

Figure 2: Combustible Gas Sample-draw Detector Flow Diagram

INLET fitting

The INLET fitting on the right side of the housing allows the gas sample to enter the
sample-draw detector. The INLET fitting accepts 1/4 in. rigid tubing. See the Installation
section on page 9 to connect tubing to the INLET fitting.

Hydrophobic Filter

The hydrophobic filter is below the main circuit board. The filter pr events particulates and
water in the incoming gas sample from damaging the flow and detection systems. Replace
the filter when it appears dirty, discolored, or clogged.

Pump

The pump is behind the main circuit board near the top 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 by the controller.

Flowmeter

The flowmeter is attached to the main circuit board near the top left corner (see Figure 1.)
You can see it through the window in the door. A ball in the flowmeter column indicates
the flow rate of the sample-draw detector. The flowmeter measures the flow in the range

0.2 to 2.0 SCFH (Standard Cubic Feet per Hour). The optimum flow rate is 1.5 SCFH.

Bypass valve

The bypass valve is to the left of the flowmeter. The bypass valve adjusts the flow rate to
the detector. 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 1.)

6 • 35-3000RK-LEL Combustible Gas Sample-Draw Detector