Nuvair PRO HE User manual

Pro He
OPERATING INSTRUCTIONS FOR
PRO HE
HELIUM ANALYZER
P/N He
Rev 1
DANGER
This instrument is designed to monitor the helium concentrations in a gas mixing
process. When processing gas mixtures intended for breathing, the instrument must
be calibrated and functioning properly. Suffocation or other fatal respiratory
complications can result from improperly calibrated or malfunctioning equipment.
Oxygen accelerates combustion. Do not use this instrument around open flames and
combustible gases, liquids or solids.
Only authorized personnel should conduct maintenance and/or servicing. Before
conducting any maintenance or servicing, consult with authorized
supervisor/manager.
Pro He Manual Rev 08/01/07 P/N He
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Pro He
Copyright © 2003
All Rights Reserved. No part of this manual may be reproduced, transmitted, transcribed, stored in a retrieval system, or
translated into any other language or computer language in whole or in part, in any form or by any means, whether it be
electronic, mechanical, magnetic, optical, manual, or otherwise, without the prior written consent of Nuvair, 2949 West 5th
Street, Oxnard, CA 93030.
Warranty
This equipment is sold subject to the mutual agreement that it is warranted by us free from defects of material and of
construction, and that our liability shall be limited to replacing or repairing at our factory (without charge, except for
transportation), or at customer plant at our option, any material or construction in which defects become apparent within one
year from the date of shipment, except in cases where quotations or acknowledgements provide for a shorter period.
Components manufactured by others bear the warranty of their manufacturer. This warranty does not cover defects caused by
wear, accident, misuse, neglect or repairs other than those performed by Nuvair or an authorized service center. We assume no
liability for direct or indirect damages of any kind and the purchaser by the acceptance of the equipment will assume all liability
for any damage, which may result from its use or misuse.
We reserve the right to employ any suitable material in the manufacture of our apparatus, and to make any alterations in the
dimensions, shape or weight of any parts, in so far as such alterations do not adversely affect our warranty.
Important Notice
This instrument provides measurement readings to its user, and serves as a tool by which valuable data can be gathered. The
information provided by the instrument may assist the user in eliminating potential hazards caused by his process; however, it is
essential that all personnel involved in the use of the instrument or its interface, with the process being measured, be properly
trained in the process itself, as well as all instrumentation related to it.
The safety of personnel is ultimately the responsibility of those who control process conditions. While this instrument may be
able to provide early warning of imminent danger, it has no control over process conditions, and it can be misused. Any
safeguards required such as locks, labels, or redundancy, must be provided by the user or specifically requested of Nuvair at the
time the order is placed.
Therefore, the purchaser must be aware of the process conditions and the potential for misuse. The purchaser is responsible for
the training of personnel, for providing hazard warning methods and instrumentation per the appropriate standards, and for
ensuring that all devices and instrumentation are calibrated, maintained and operated properly.
Nuvair, or the manufacturer of this instrument, cannot accept responsibility for conditions beyond its knowledge and control. No
statement expressed or implied by this document or any information disseminated by the manufacturer or its agents, is to be
construed as a warranty of adequate safety control under the user’s process conditions.
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Pro He
Specific Model Information
The instrument for which this manual was supplied may incorporate one or more options not
supplied in the standard instrument. Commonly available options are listed below.
CE CONFORMITY: This Nuvair PRO HE Analyzer meets or exceeds all requirements
of the Commonwealth of Europe (CE) for Radio Frequency Interference and
Electromagnetic Interference (RFI/EMI) protection.
PRO HE MCWHE: Wall-mountable instrument with view window for helium analysis.
PRO HE MCWHEO2: Wall-mountable instrument with view window for helium
analysis.
PRO HE MCPHE: Battery operated portable instrument for helium analysis.
Optional AC to DC Adapter: Power instrument directly from 115VAC US plug source.
Optional International Power Adapter: Powers instrument directly from an AC power
source 100-240 VAC 50/60 Hz CE approved. Includes US and 3 international AC plugs.
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Pro He
Safety Messages
Your safety and the safety of others are very important. We have provided many important
safety messages in this manual. Please read these messages carefully.
A safety message alerts you to potential hazards that could hurt you or others. Each safety
message is associated with a safety alert symbol. These symbols are found in the manual and inside
the instrument. The definition of these symbols is described below:
GENERAL WARNING/CAUTION: Refer to the instructions for details on the specific danger.
These cautions warn of specific procedures which if not followed could cause bodily
Injury and/or damage the instrument.
CAUTION: HOT SURFACE WARNING:This warning is specific to heated components within the
instrument. Failure to heed the warning could result in serious burns to skin and
underlying tissue.
WARNING: ELECTRICAL SHOCK HAZARD:Dangerous voltages appear within this instrument. This
warning is specific to an electrical hazard existing at or nearby the component or
procedure under discussion. Failure to heed this warning could result in injury and/or
death from electrocution.
TECHNICIAN SYMBOL: All operations marked with this symbol are to be performed by qualified
maintenance personnel only.
NOTE: Additional information and comments regarding a specific component or procedure
are highlighted in the form of a note.
CAUTION: THE ANALYZER SHOULD ONLY BE USED FOR THE PURPOSE AND IN THE
MANNER DESCRIBED IN THIS MANUAL.
No
Symbol
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Pro He
CAUTION: THE PRO HE ANALYZER ELECTRONICS ARE NOT WATER RESISTANT. DO
NOT ALLOW WATER INSIDE THE ENCLOSURE.
IF YOU USE THE ANALYZER IN A MANNER OTHER THAN THAT FOR WHICH IT
WAS INTENDED, UNPREDICTABLE BEHAVIOR COULD RESULT POSSIBLY
ACCOMPANIED WITH HAZARDOUS CONSEQUENCES.
This manual provides information designed to guide you through the installation, calibration and
operation of your new analyzer. Please read this manual and keep it available.
Occasionally, some instruments are customized for a particular application or features and/or
options added per customer requests. Please check the front of this manual for any additional
information in the form of an Addendum which discusses specific information, procedures, cautions
and warnings that may be peculiar to your instrument.
Manuals do get lost. Additional manuals can be obtained from Nuvair at the address given in the
Appendix. Some of our manuals are available in electronic form via the internet. Please visit our
website at: www.nuvair.com.
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Pro He
Table of Contents
Safety Messages ..........................................................................iv
Table of Contents.........................................................................vi
List of Figures.............................................................................viii
Introduction .................................................................................11
1.1 Overview 11
1.2 Features 13
1.3 Options 13
1.4 Applications 13
Setup............................................................................................14
2.1 Unpacking the Analyzer 14
2.2 Mounting the Analyzer (Wall-Mount Unit) 14
2.3 AC Power Connections 15
2.4 Battery Test (Portable Model Only) 16
2.5 Battery Installation (Portable Model Only) 16
2.6 Calibration 17
Operation.....................................................................................20
3.1 Operation/Start-up 20
3.1.1 Powering Up 20
3.1.2 Attaching the Sample Gas 20
Maintenance ................................................................................22
4.1 Battery Replacement 22
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Pro He
Appendix......................................................................................24
A.1 Specifications 24
A.2 Spare Parts List 26
A.3 Helium/Air Chart 27
A.4 Material Safety Data Sheet 30
Index.............................................................................................31
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Pro He
List of Figures
Figure 1-1: Wall-mountable PRO HE ............................................12
Figure 1-2: PRO HE—Portable Configuration...............................12
Figure 2-1: Mounting Dimensions .................................................15
Figure 2-2: Power Adapter Port (Wall Mount) ...............................15
Figure 2-3: Power Adapter Port (Portable Model) .........................16
Figure 2-4: Battery Installation ......................................................17
Figure 2-5: Typical Sample System with Calibration.....................19
19
Figure 3-1: Typical Setup Flow Diagram.......................................21
Figure 4-1: Battery Disposition......................................................23
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Pro He
DANGER
COMBUSTIBLE GAS USAGE
WARNING
This is a general-purpose instrument designed for use in a non-hazardous area. It is
the customer's responsibility to ensure safety. Combustible gases should not be
present in the immediate area nor should this instrument be used near an open flame
or ignition source.
Helium and nitrogen, while inert, can pose a suffocation risk. The customer must
eliminate the possibility of displacing atmospheric air with helium or nitrogen at or
near the instrument during the mixing or analysis process.
The customer must also ensure that the principles of operating this equipment are
well understood by the user. Misuse of this product in any manner, tampering with its
components, or unauthorized substitution of any component may adversely affect the
safety of this instrument.
Since the use of this instrument is beyond the control of Nuvair, no responsibility by
Nuvair, its affiliates, and agents for damage or injury from misuse or neglect of this
equipment is implied or assumed.
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Pro He
BLANK
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Pro He Introduction
Introduction
The Nuvair PRO HE is a dedicated instrument designed to accurately monitor the composition
of a gas during mixing or cylinder filling operations. A LCD mounted on the front panel of the
instrument displays the percentage of helium during the mixing operation.
There are two basic configurations available both of which offer oxygen analysis as an option.
The wall-mountable unit is housed in an enclosure equipped with a window for viewing the helium
displays. It is powered by a plug-in 6V DC adapter which uses a conventional 120VAC source (100-
240 VAC 50/60 Hz optional).
The portable instrument is housed in a rugged high-impact plastic watertight enclosure. It has a
molded-in handle for easily transporting the instrument to the mixing or process area. Both models, the
standard wall-mount and the portable instrument, use corrosive-resistant materials where applicable for
enhanced durability in salt air or spray environments. The wall-mount model is shown in Figure 1-1 and the
portable instrument is shown in Figure 1-2.
1.1 Overview
The PRO HE analyzes the helium concentrations in a gas mixture. The gas to be monitored is drawn
into the analyzer and passed to the sensor network.
The sample gas is then directed to a thermal conductivity sensor. This sensor provides a signal that is
proportional to the difference in conductivities between the components of the gas mixture. A
microprocessor compares the sensor output to data contained in an onboard chip and converts the raw data
into a linearized signal that is sent to the helium LCD display.
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Pro He Introduction
Accuracy is maintained to ± 1% across the entire 0-100% analysis range (He) of the instrument
at constant temperature (25°C) at constant pressure (atmospheric).
Figure 1-1: Wall-mountable PRO HE
Figure 1-2: PRO HE—
Portable Configuration
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Pro He Introduction
1.2 Features
The following features are included in the PRO HE:
Two independent easy to read LCD display for He•
•
•
•
•
•
•
•
•
•
•
•
•
Low power consumption—up to 150 operational hours on 4 C-cell batteries (portable unit)
Convenient front panel ON-OFF power switch with Battery Test
Front panel mounted Span and Zero calibration potentiometers
Linearized He channel output over the entire analysis range
Accessible 1/8” NPT inlet and outlet gas connections for easy setup (wall mount unit)
Microprocessor controlled electronics
Long-life, low temperature solid state thermal conductivity sensor for accurate helium
analysis
ABS enclosure for wall-mounting—rugged water resistant plastic housing for portable
model
Low pressure power inflator hose sampling adapter
1.3 Options
AC/DC adapter to power either unit using 120VAC power
AC/DC adapter for universal power (100-240 VAC) with 4 interchangeable international
AC power plugs (CE rated)
1.4 Applications
The PRO HE is specifically offered to the diving industry where specific mixtures of Helium
in air are required for technical diving. The PRO HE will allow on-site confirmation of gas
mixtures prepared for divers. It is also useful in the gas mixing process during cylinder charging
where adjustments to the gas composition can be made based on the real-time analysis of the gas
mixture.
Other applications include:
Gas purification and air liquefaction process control
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Pro He Setup
Setup
Installation of the analyzer includes:
Unpack unit•
•
•
•
•
•
Mount unit
Install sensor
Install batteries (portable unit only)
Make gas and power connections
Calibrate and test the installation
Also covered in this section are battery issues, replacing the battery and replacing micro-fuel
cells.
2.1 Unpacking the Analyzer
The PRO HE is shipped fully functional and ready to install except for installing and batteries
(portable unit only). Carefully unpack the analyzer and inspect it for damage.
2.2 Mounting the Analyzer (Wall-Mount Unit)
The PRO HE is designed to mount and operate in a general-purpose area only. The instrument
is not designed to accept or handle hazardous gases.
CAUTION: USING OR MONITORING OXYGEN LEVELS ABOVE ATMOSPHERIC
COMPOSITION (20.9%) CAN BE HAZARDOUS. WHILE OXYGEN IS NOT
COMBUSTIBLE OR EXPLOSIVE, ITS PRESENCE ACCELERATES AND
PROMOTES COMBUSTION. HIGH LEVELS OF OXYGEN WILL MAKE MOST
MATERIALS COMBUSTIBLE INCLUDING METALS. DO NOT USE OXYGEN
LEVELS ABOVE 20.9% IN THE PRESENCE OF ANY FLAME OR IGNITION
SOURCE.
Refer to Figure 2-1 and the Outline Drawing in the Appendix for mounting dimensions. The location
should be close to the process line to avoid excessive run lengths of tubing. The plastic wall mount
enclosure is not watertight. It should not be exposed to water or spray while in use due to the exposed
external power adapter inlet. The AC adapter used on this instrument is not water resistant. Care must also
be taken not to allow water entry into the power adapter inlet port.
CAUTION: POTENTIAL WATER DAMAGE COULD OCCUR IF THE POWER ENTRY ACCESS
PORT IS EXPOSED.
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Pro He Setup
Mount the instrument so that it does not restrict or cause the sample return line to kink. The sample
return port must not be restricted and must be vented at atmospheric pressure.
Figure 2-1: Mounting Dimensions
2.4 AC Power Connections
Instrument power for the standard wall-mountable model is supplied by a 6VDC power adapter
that is plugged into the side of the analyzer as shown in Figure 2-2.
Figure 2-2: Power Adapter Port (Wall Mount)
The portable model is powered from 4 C-cell batteries, which must be installed prior to placing
the instrument in service. See Section 2.6. The portable unit can also be powered using the optional 6
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Pro He Setup
VDC power adapters, P/N A558 (US) or A555 (CE). When using the adapter, insert the jack into the
port on the side of the front panel near the ON/OFF/ BATT TEST switch as shown in Figure 2-3.
This figure also shows the internal pressure vent port which allows the instrument to vent and return
to atmospheric pressure before the lid is opened.
Figure 2-3: Power Adapter Port (Portable Model)
2.5 Battery Test (Portable Model Only)
A battery test function is available from the front panel and should be used prior to using the
instrument. To test the batteries, turn the OFF-ON switch to the BATT TEST position. A fresh set of
batteries will show a reading of 120. If the reading is 100 or below, you must change the batteries to
maintain the accuracy of this instrument.
2.6 Battery Installation (Portable Model Only)
Before using the portable model for the first time, 4 C-cell batteries must be installed.
Note: Do not use rechargeable batteries. This type of battery does not provide the required
voltage to power the instrument.
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Pro He Setup
To install the batteries, remove the 2 screws securing the battery compartment lid. Lift out the
compartment cover and install the batteries noting the polarity indicated on the label molded into the
battery holder. See Figure 2-4.
When replacing batteries, for best results use only long-life alkaline batteries. The monitor can
be run for up to 150 hours on a fresh set of batteries.
Figure 2-4: Battery Installation
2.7 Calibration
The analyzer is supplied fully calibrated from the factory but will require calibration checks and
recalibration every 30 days or less to maintain the best accuracy.
Zero Calibration (helium sensor)
Note: To zero the helium sensor, there must be no residual gases other than air in the
sample line of the instrument. Step 1 below is designed to purge the sample line using
air.
1. With the air source still attached make sure the flow is adjusted between 0.2 and 2 SLPM.
Flow air for at least 2 minutes to purge all other gases from the sample line.
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Pro He Setup
2. After 2 minutes and with air still flowing in the sample line, adjust the helium zero
potentiometer on the front panel until a reading on the helium display reads slightly above
zero, for instance, 4% helium.
3. Slowly rotate the potentiometer and watch the helium display as it slowly decreases
toward zero. Once the helium reading changes from 0.2% to 0.1% stop the adjustment
process.
The analyzer is now properly zeroed.
Note: This procedure is necessary to avoid producing “negative” readings. The display is
incapable of displaying negative values and will read zero even if the potentiometer is
turned additionally after the zero point is approached.
Span Calibration (helium sensor)
Note: The span is set using the helium display
1. Attach the 100% helium gas to the sample inlet and adjust the flow to between 0.2 and 2.0
SLPM.
2. While helium is purging the sample line, watch the oxygen display. When the oxygen
concentration decreases to 0.2–0.0%, adjust the helium span potentiometer on the front panel to
set the display (helium) to 100.0% ±0.2% helium.
The instrument is now calibrated
You should verify that the analyzer reads 20.9% O2 and 00.0 ±0.2% He with air flowing through
the instrument and 0.00 ±0.2% O2 and 100.0% ±0.2% He when flowing 100% He.
For additional calibration notes, see Section A.3 in the Appendix. The analyzer is now ready to
be placed in service.
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Pro He Setup
Figure 2-5: Typical Sample System with Provisions for Calibration
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Pro He Operation
Operation
3.1 Operation/Start-up
Using the PRO HE analyzer basically involves three steps:
Powering up the instrument
•
•Attach a sample gas
3.1.1 Powering Up
Turn the instrument on using the power switch and allow it to operate for 30 seconds.
3.1.2 Attaching the Sample Gas
See Figure 3-1. On the portable unit, attach the sample tube to the gas source and adjust the flow
rate to 0.2—2.0 SLPM. For the wall mount unit, attach the sample gas to the sample in port and
adjust the flow to 0.2—2.0 SLPM. The actual sample flow rate is not critical, but it is important that
the flow rate does not exceed 2.0 SLPM. The instrument incorporates small gas passages inside the
sample block. A high gas flow rate will pressurize the helium sensor and cause it to indicate an
incorrect gas concentration.
The analyzer display reading should become stable in less than a minute. Most of the time
required for the analyzer’s reading to stabilize is caused by gas sampling propagation delays. This is
the time required for the gas sample to purge through the regulators, gas lines and fittings. Depending
on the sample system employed, it may require several minutes for the gas sample to reach the
analyzer and become stable.
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