Ametek 388 Ranarex User manual

388 Ranarex Portable Gas Gravitometer
USER MANUAL
PN RI-212, Rev. L
LOCK
UNLOCK
ZERO
ADJUST
RANAREX
SPECIFIC GRAVITY

To obtain a PDF of this manual, visit our Products page at www.ametekpi.com.
Copyright Notice © 2023 AMETEK Process Instruments. All rights reserved.
The information and descriptions in this document are the sole property of AMETEK Process Instruments and may not be copied, reproduced, disseminated, or
distributed without explicit written permission from AMETEK Process Instruments.
The statements, congurations, technical data, and recommendations in this document are believed to be accurate and reliable at the time of this publication,
but AMETEK Process Instruments assumes no responsibility or liability for any errors or inaccuracies that may appear in this document.
AMETEK Process Instruments is not responsible for any infringement of patents or other rights of third parties that may result from the use of this document. The
content of this document is furnished for informational purposes only, is subject to change without notice, and does not represent a commitment or guaranty by
AMETEK Process Instruments.
AMETEK Process Instruments makes no warranty, express or implied, with respect to the content of this document. AMETEK Process Instruments shall not be
liable for any loss or damage, including consequential or special damages, resulting from any use of this information, even if loss or damage is caused by AMETEK
Process Instruments as a result of negligence or any other fault.

PN RI-212, Rev. L
Contents
Important Safety Warnings, Cautions, and Notes..........................................................................vi
Electrical Safety .........................................................................................................................................vii
H2S Warning................................................................................................................................................vii
Grounding...................................................................................................................................................vii
Warning Labels........................................................................................................................................ viii
Environmental Information – WEEE................................................................................................. viii
OVERVIEW .............................................................................................................................1-1
388 Ranarex Portable Gas Gravitometer........................................................................................1-1
Theory of Operation ..............................................................................................................................1-1
Zero Position – Reference Air Only...........................................................................................1-2
Reading Position – Unknown Gas and Reference Air ........................................................1-3
Measuring Relative Density ................................................................................................................1-4
Selector Valve...................................................................................................................................1-4
Motor...................................................................................................................................................1-4
Options.......................................................................................................................................................1-5
INSTALLATION AND START-UP............................................................................................2-1
Pre-Installation Requirements ...........................................................................................................2-2
Storage Prior to Installation ........................................................................................................2-2
Uncrating and Inspecting the Ranarex Gas Gravitometer...............................................2-3
Mechanical Installation.........................................................................................................................2-4
Location and Environment..........................................................................................................2-4
Permanent Mounting ...........................................................................................................2-4
Electrical Installation .............................................................................................................................2-6
DC-AC Power Inverter – Alternate Powering Method .......................................................2-6
Damaging the Inverter......................................................................................................... 2-6
Installing the Inverter............................................................................................................2-7
Check Vehicle Polarity ...................................................................................................2-7
Choosing a Location......................................................................................................2-7
Cable Installation........................................................................................................... 2-8
Inverter Connections ..................................................................................................... 2-8
Connection Polarity.......................................................................................................2-9
Inverter Operation ...............................................................................................................2-10
Stopping the Inverter...................................................................................................2-10
Regulating the Inverter Voltage................................................................................2-10
Operating Other Equipment .............................................................................................2-11
Typical Loads.................................................................................................................2-11
Contents | iii

PN RI-212, Rev. L
Conditioning the Gas and Air Samples........................................................................................ 2-12
Dry Reference Air .........................................................................................................................2-12
Pressure Requirements .......................................................................................................2-12
Temperature Requirements...............................................................................................2-12
Moisture Content of Gases.................................................................................................2-13
Filtering Out Liquids ............................................................................................................2-13
Setting Up the System.......................................................................................................................2-14
Preparing the Dryer .................................................................................................................... 2-14
Attaching the Outlet Hoses...................................................................................................... 2-15
Gas Filter..........................................................................................................................................2-15
Gas Temperature.......................................................................................................................... 2-16
Adjusting Sample Temperature.............................................................................................. 2-16
Sample Gas Connections..........................................................................................................2-16
OPERATION ...........................................................................................................................3-1
Pointer Lock..............................................................................................................................................3-1
Operating the Ranarex Gas Gravitometer .....................................................................................3-2
Starting the Gravitometer............................................................................................................3-2
Reading the Gas ..............................................................................................................................3-3
Shutting Down the Gravitometer.............................................................................................3-3
Helpful Operation Tips..........................................................................................................................3-4
Zero Adjustment.............................................................................................................................3-4
Response Time.................................................................................................................................3-4
Over-Pressure Protection.............................................................................................................3-4
Purging to 1.000 After Measuring a Gas.................................................................................3-4
MAINTENANCE AND TROUBLESHOOTING.........................................................................4-1
Safety Considerations ...........................................................................................................................4-2
Aftermarket Excellence and Long-Term Commitment to Safety and Quality ..................4-3
Recommended Spare Parts Lists.......................................................................................................4-4
Operating Mechanism ..................................................................................................................4-4
General Spare Parts........................................................................................................................4-5
Accessories........................................................................................................................................4-5
Calibration Pulley............................................................................................................................4-5
Diagnostic Flowcharts ..........................................................................................................................4-6
Air and Gas Flow Checks ..............................................................................................................4-7
Impeller Speed Check ...................................................................................................................4-7
Frictionless Indicator Response.................................................................................................4-8
Internal Leak Check........................................................................................................................4-9
Check the Indicator Balance ....................................................................................................4-10
Check the Silica Gel in the Dryer............................................................................................4-10
Gravitometer Calibration ..........................................................................................................4-10
iv | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Maintenance.......................................................................................................................................... 4-11
Preparing the Gravitometer for Service............................................................................... 4-11
Removing the Front and Rear Covers..............................................................................4-11
Removing the Indicating Scale .........................................................................................4-11
Removing the Front Chamber Cover...............................................................................4-12
Removing the Rear Chamber Cover ................................................................................4-12
Cleaning and Servicing the Selector Valve......................................................................... 4-13
Cleaning the Selector Valve...............................................................................................4-13
Polishing the Valve...............................................................................................................4-13
Adjusting the Pointer Lock....................................................................................................... 4-14
Cleaning, Adjusting, and Replacing the Connecting Tape ........................................... 4-15
Tracking the Tape.................................................................................................................4-15
Cleaning the Tape ................................................................................................................4-15
Replacing the Tape ..............................................................................................................4-15
Idler Bearing ..........................................................................................................................4-15
Replacing the Impeller Bearings ............................................................................................ 4-16
SPECIFICATIONS....................................................................................................................5-1
388 Ranarex Portable Gas Gravitometer ........................................................................................5-1
CALIBRATION........................................................................................................................6-1
Calibrating the Ranarex Gravitometer ............................................................................................6-1
Zero Adjust........................................................................................................................................6-1
Sensitivity ..........................................................................................................................................6-1
Too Sensitive............................................................................................................................6-1
Not Sensitive Enough............................................................................................................ 6-1
Span Adjustment............................................................................................................................6-2
Calibration Pulley....................................................................................................................................6-3
Test Procedure for Calibration Pulley.......................................................................................6-3
DRAWINGS ............................................................................................................................7-1
Contents | v

PN RI-212, Rev. L
Important Safety Warnings, Cautions, and Notes
WARNINGS, CAUTIONS, and NOTES contained in this manual emphasize critical
instructions as follows:
Important information that should not be overlooked.
An operating procedure which, if not strictly observed, may result in personal
injury or environmental contamination.
An operating procedure which, if not strictly observed, may result in damage
to the equipment.
vi | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Electrical Safety
Up to 2 kV may be present in the analyzer housings. Always shut down power
source(s) before performing maintenance or troubleshooting. Only a qualied electri-
cian should make electrical connections and ground checks.
Any use of the equipment in a manner not specied by the manufacturer may impair
the safety protection originally provided by the equipment.
H2S Warning
High Concentrations of H2S are extremely hazardous to personnel. The Ranarex Gas
Gravitometer with sour gas protection provides physical protection for the Ranarex
Gas Gravitometer only. Precautions should be taken to protect personnel and all local
safety regulations concerning hazardous gases should be followed. Do not use the
Ranarex Gas Gravitometer in any enclosed space or in any area where the concentra-
tion of H2S may exceed 10 ppmv for any length of time. Failure to do so can result in
serious harm or death.
Grounding
Instrument grounding is mandatory. Performance specications and safety protection
are void if instrument is operated from an improperly grounded power source.
Verify ground continuity of all equipment before applying power.
Contents | vii

PN RI-212, Rev. L
Warning Labels
These symbols may appear on the instrument to alert you of existing conditions.
Protective Conductor Terminal
(BORNIER DE L’ECRAN DE PROTECTION)
Schutzerde
Caution – Risk of electric shock
(ATTENTION – RISQUE DE DÉCHARGE ÉLECTRIQUE)
Achtung – Hochspannung Lebensgefahr
Caution – Refer to accompanying documents
(ATTENTION – SE RÉFERER AUX DOCUMENTS JOINTS)
Achtung – Beachten Sie beiliegende Dokumente
CAUTION – Hot Surface
(ATTENTION – SURFACE CHAUDE)
Achtung – Heiße Oberäche
Environmental Information – WEEE
This AMETEK product contains materials that can be reclaimed and recycled. In some
cases the product may contain materials known to be hazardous to the environ-
ment or human health. In order to prevent the release of harmful substances into the
environment and to conserve our natural resources, AMETEK recommends that you
arrange to recycle this product when it reaches its“end of life”.
Waste Electrical and Electronic Equipment (WEEE) should never be disposed of in a
municipal waste system (residential trash). The Wheelie Bin marking on this product is
a reminder to dispose of the product properly after it has completed its useful life and
been removed from service. Metals, plastics, and other components are recyclable and
you can do your part by doing one of the following steps:
• When the equipment is ready to be disposed of, take it to your
local or regional waste collection administration for recycling.
• If you need further assistance in recycling your AMETEK product,
contact us through our Customer Support page at
www.ametekpi.com/customersupport/aftermarket.
viii | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Overview
388 Ranarex Portable Gas Gravitometer
The Ranarex Gas Gravitometer measures the specic gravity (SG) of gases as
compared to air. For many industrial process gases there is a denite connec-
tion between the analysis of the gas mixture and its specic gravity. When
the specic gravity is involved in the analysis of the total mixture, or when the
instruments are used with orice metering in gas volume, they are graduated
in specic gravity. When the gravimetric principle can be applied, Ranarex Gas
Gravitometer excel over more complex and costly analyzers in total perfor-
mance.
Theory of Operation
The Ranarex principle and design are simple. The chassis of the Gravitometer
forms two (2) cylindrical, gas-tight measuring chambers; each has a separate
inlet and outlet connection. In each chamber there is an Impeller Wheel and an
Impulse Wheel, both with axial vanes. These wheels are mounted on separate
shafts. An electric motor and drive belt rotate the impellers at the same speed
and in the same direction. The impellers draw a continuous ow of air into
their respective chambers. They spin the gas and air against the vanes of the
corresponding Impulse Wheels. As the spinning gas and air impinge against
the vanes, they create torques on the Impulse Wheels that are proportional to
the density of the gas and of the air.
These torques are transmitted from the chambers to two (2) external mea-
suring wheels. A exible tape is wrapped on the Measuring wheel rims in
the crossed direction so that the torque creates two (2) opposing forces. The
measuring wheels are restrained from continuous rotation, but a dierence
between the torques allows limited motion of the entire system. The measur-
ing system divides the torque of the gas by the torque of the air. This is the
same ratio as the density of the gas divided by the density of the air which is
the specic gravity.
The rim of the gas Measuring wheel is contoured so that it rotates through
equal angles for equal changes in specic gravity. The uniform motion of the
gas Measuring wheel is transmitted by a link to the readout elements; these
can be either an indicator, a recorder, an electronic transmitter, or high/low
contacts. To ensure accuracy, the gas sample and the Reference air must be
measured at ambient temperature, at barometric pressure, and at equal hu-
midity content (either humidied or dry).
Overview |1-1

PN RI-212, Rev. L
Zero Position – Reference Air Only
Figure 1-1.1 shows the position of the Cam and Reference Wheel when the Ref-
erence air is admitted into both measuring chambers. In this case, the Impeller
Wheel torques are equal. Because of this condition and the linear prole of the
cam, the graduated dial is calibrated to indicate 1.000. An Air Dryer is built into
the Gravitometer to dry incoming ambient air for use as the Reference air.
Ta
Ra
Ra
Ta
Fa
Measuring Wheel
Reference Wheel
ZERO
POSITION
Fa
Figure 1-1.1.
Zero position, Reference air
only.
1-2 | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Reading Position – Unknown Gas and Reference Air
Figure 1-1.2 shows the position of the Cam and Reference Wheels when an
unknown gas is admitted to the upper chamber, and Reference air is admitted
into the lower chamber. The lighter gas (in the upper chamber) creates a small-
er torque than the air in the lower chamber. As a result, the cam will rotate
until the cam radii allows the opposing torques to balance. The cam rotation is
calibrated to indicate the ratio of the torques, or relative density.
Tg
Rg
Ra
Ta
Fa
Measuring Wheel
Reference Wheel
READING
POSITION
Fa
Figure 1-1.2.
Reading position, unknown
gas.
Overview |1-3

PN RI-212, Rev. L
Measuring Relative Density
The Ranarex Gravitometer measures relative density in accordance with the
denition:“The ratio of the density of the gas, under observed conditions of
pressure and temperature, to the density of dry air at the same pressure and
temperature.”
To measure relative densities above 1.000, the unknown gas is admitted to the
lower chamber and the dry Reference air is admitted to the upper chamber.
The principle of operation is the same. The graduated dial has two (2) Scales.
The inner (RED) Scale is used for relative densities below 1.000 and the outer
(BLACK) Scale is used for relative densities above 1.000.
Because of the nature of the Gravitometer design, pressures and temperatures
of the gas and Reference air are equalized. Any changes in pressure, tempera-
ture, and motor speed aect both torques equally. Since the torques produce
opposing forces, the eects of varying pressure, temperature and motor speed
are cancelled.
Selector Valve
The Gravitometer is equipped with a Selector Valve that is used to direct the
gas sample and dry Reference air to the correct chambers. The three (3) valve
positions are used for:
• Checking the instrument Zero.
• Measuring gas relative densities below 1.000
• Measuring gas relative densities above 1.000.
Motor
The motor is designed for operation on 115 VAC/230 VAC, ±10 %, 50/60 Hz.
When the Gravitometer is used in an area where AC power is not available, an
optional DC-AC Inverter can be used to convert the DC voltage supplied by an
automobile alternator or other DC source to the correct AC voltage.
The unit can be operated from the oor, a workbench, or hung from the wall
and operated from a standard AC power supply or from a 12-Volt vehicle bat-
tery using a DC-AC Inverter.
1-4 | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Options
The available options for use with the Ranarex Gas Gravitometer include:
•DC-AC Power Inverter: 12 VDC to 115 VAC or 230 VAC.
•Selectable AC power, 115/230 VAC.
•Alodyne treatment for sour gas applications.
Overview |1-5

PN RI-212, Rev. L
This page intentionally left blank.
1-6 | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Installation and Start-Up
The use and operation of this analyzer must be in accordance with all
of the end user and local regulatory standards and procedures. There
are no operator-serviceable components inside the analyzer. Refer
servicing to qualied personnel.
Before powering up the analyzer, review and follow all safety informa-
tion in this chapter. This information describes procedures to follow to
avoid personal injury and/or damage to the equipment. All regula-
tory agency and company safety procedures for your jurisdiction
must be followed.
Installation and Start-Up |2-1

PN RI-212, Rev. L
Pre-Installation Requirements
Storage Prior to Installation
If the analyzer is stored for any period of time prior to installation, store the
equipment in an environment where it is not subject to dripping or splashing
liquids, corrosive gases, high humidity, or excessive heat or cold. Recommend-
ed storage conditions include:
Temperature: -20 °C–60 °C (-4 °F–140 °F)
Relative Humidity: Maximum 95 %, non-condensing
Failure to comply with these storage conditions will void your warranty.
2-2 | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Uncrating and Inspecting the Ranarex Gas
Gravitometer
The Ranarex Gas Gravitometer and its accessories were tested and inspected
before the analyzer was shipped from the factory. Carefully uncrate the analyz-
er, remove any packing material and check for damage. If any damage is found,
notify AMETEK as soon as possible and notify the shipper.
The Ranarex Gas Gravitometer weighs approximately 23 kg (50 lb).
Use caution when lifting it from its crate.
Accessories shipped with the standard 115 VAC or 230 VAC Ranarex Gas Gravi-
tometer include:
• (1) Electric cord (6 feet), 18-gauge cable with male and female plugs.
• (1) 1-1/4 lb can of Silica Gel.
• (1) Filling funnel.
• (1) 388 Ranarex Portable Gas Gravitometer User Manual (Part No. RI-212).
Additional accessories shipped with the Ranarex Gas Gravitometer when it will
be powered using a 12-Volt DC battery (unless excluded by the customer):
• (1) Ranarex DC-AC Power Inverter (12 VDC to 115 VAC or 230 VAC).
• (2) Battery cables (16 feet) 12-gauge wire with battery clips.
The “DC-AC Power Inverter” instructions are included in this chapter.
Installation and Start-Up |2-3

PN RI-212, Rev. L
Mechanical Installation
Read this entire section before beginning installation of the Ranarex
Gas Gravitometer. Failure to do so, and/or use of the analyzer in
a manner not specied in this manual, may impair the protection
against re, electrical shock, and personal injury originally provided
by this equipment.
Location and Environment
The Ranarex Gas Gravitometer should not be near hot or cold objects. You
must allow at least 5" (12.7 cm) of clearance on the left side and 3" (2.6 cm) on
the right side for making connections and for normal operating functions.
Permanent Mounting
If the instrument will be permanently mounted, it must be secured with (4)
1/4-20 machine screws (not provided). The screws mount through the holes in
the Gravitometer base. See Figure 2-1 for mounting dimensions and the loca-
tion of the mounting holes.
Figure 2-1.
Ranarex Gas Gravitometer
outside and mounting
dimensions.
7 5/8
13 5/8
10 3/4 16 3/4
11 1/8
13
1 3/4
2 1/8
1 5/8
RANAREX
2-4 | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering

PN RI-212, Rev. L
Figure 2-2 illustrates the locations of connections and external controls.
Figure 2-2.
Ranarex Gas Gravitometer –
location of connections and
controls.
LOCK
UNLOCK
ZERO
ADJUST
RANAREX
SPECIFIC GRAVITY
Light Gas
Outlet
Zero Adjust
Electric
Connection
Heavy Gas
Outlet
Pointer Lock Knob
Gas Sample
Flowmeter
Selector
Valve
Air Dryer
Instruction
Plate
Installation and Start-Up |2-5

PN RI-212, Rev. L
Electrical Installation
DC-AC Power Inverter – Alternate Powering Method
The DC-AC Power Inverter, which can be purchased and used as an alternate
powering method, is designed primarily for operating the Ranarex Gas Gravi-
tometer. They are durable, transistorized units with no moving parts.
Part No. Description DC Input at Battery Posts AC Output
CH300-27404 12 VDC/115 VAC, 500 W 12.0–14.2 VDC 110–125 VAC, 60 Hz, 500 W
CH300-28656 12 VDC/230 VAC, 1000 W 12.0–14.2 VDC 220–230 VAC, 50 ±0.5 Hz, 1000 W
Do not misuse the Inverter. Excessive or extended overload will cause
permanent damage.
Damaging the Inverter
Operating under the following conditions will result in permanent damage to
the Inverter transistor:
• With reversed DC polarity.
• With“no-load” for more than a few minutes.
• With long or large overload.
• With a“short” in the AC load.
2-6 | 388 Ranarex Portable Gas Gravitometer – Chandler Engineering