Apex Digital Precision Gas Flow Meter User Manual

16 Series Mass and Volumetric Flow Meters

Precision Gas Flow Meter

Operating Manual

Notice: The manufacturer reserves the right to make any changes and improvements to the products described in this manual at any time and without notice. This manual is copyrighted. This document may not, in whole or in part, be copied, reproduced, translated, or converted to any electronic medium or machine readable form, for commercial purposes, without prior written consent from the copyright holder.

Note: Although we provide assistance on our products both personally and through our literature, it is the complete responsibility of the user to determine the suitability of any product to their application.

The manufacturer does not warrant or assume responsibility for the use of its products in life support applications or systems.

Wide-Range Laminar Flow Element Patent:

The wide-range laminar ow element and products using the wide-range laminar ow element are covered by U.S. Patent Number: 5,511,416. Manufacture or use of the wide-range laminar ow element in products other than products licensed under

said patent will be deemed an infringement.

10/24/06 Rev. 0 DOC-APEXMAN16

Table of Contents Page

Installation 5 Plumbing Mounting Application

Power and Signal Connections 6 RS-232 Digital Output Signal 7 Standard Voltage (0-5 Vdc) Output Signal 7 Optional 0-10 Vdc Output Signal 7 Optional Current (4-20 mA) Output Signal 7 Optional 2nd Analog Output Signal 7 M Series Mass Flow Meter Operation 10

Main Mode Tare Gas Absolute Pressure Gas Temperature Volumetric Flow Rate 11 Mass Flow Rate Flashing Error Message 11

Select Menu Mode 12 Gas Select Mode 12 Communication Select Mode 13 Unit ID 13

Baud Data Rate Manufacturer Data Mode

V Series Volumetric Flow Meter Operation 15

Main Mode Tare Flashing Error Message 16

Select Menu Mode 16 Gas Select Mode 16 Communication Select Mode 16

Manufacturer Data Mode

RS-232 Output and Input 16 Conguring HyperTerminal® 16 Changing from Streaming to Polling Mode 17

Tare

Gas Select 17

5 5 5

10 10 11 11

13 13

15 15

Table of Contents Page

Collecting Data Data Format Sending a Simple Script File to HyperTerminal® 20 Operating Principle Gas Viscosity 21 Other Gases

Volume Flow vs. Mass Flow 23 Volumetric Flow and Mass Flow Conversion 23

Compressibility

Standard Gas Data Tables 24 Gas Viscosities and Densities Table 25 Volumetric Flow Meters Under Pressure 26

Troubleshooting 27 Maintenance and Recalibration Warranty Technical Specications 29 Dimensional Drawings

Additional Information

Option: Totalizing Mode Option: Battery Pack Accessories Flow Conversion Table Calibration Certicate Pocket 40

19 19

36 37 39 39

Table of Figures

Figure 1. 8 Pin Mini-DIN Connector

Figure 2. Mini-DIN to DB-9 Connection for RS-232 Signals 8 Figure 3. Typical Multiple Device (Addressable) Wiring Conguration 8

Figure 4. Optional Industrial Connector

Figure 5. Proper Set Up for Remote Tare on Meters 9 Figure 6. Main Mode Display, M Series Flow Meter 10 Figure 7. Select Menu Display 12 Figure 8. Gas Select Display 12 Figure 9. Communication Select Display 13

Figure 10. Manufacturer Data Display

Figure 11. Main Mode Display, V Series Flow Meter 15

Thank you for purchasing an Apex Gas Flow Meter. Please take the time to nd and read the information

contained in this manual. This will help to ensure that you get the best possible service from your instrument. This manual covers the following Apex instruments:

M Series 16 Bit Mass Gas Flow Meters V Series 16 Bit Volumetric Gas Flow Meters

Installation

Plumbing

All M or V Series Gas Flow Meters are equipped with female inlet and outlet port connections. Because the ow meters set up a laminar ow condition within the ow body, no straight runs of pipe are required upstream or downstream of the meter. The inlet and outlet ports are equal in size and symmetric (inline). The port sizes (process connections) and mechanical dimensions for different ow ranges are shown on pages 29-32.

Meters with 10-32 ports have o-ring face seals and require no further sealant or tape. On other meters,

avoid the use of pipe dopes or sealants on the ports as these compounds can cause permanent damage

to the meter should they get into the ow stream. Use of thread sealing Teon tape is recommended to prevent leakage around the threads. When applying the tape, avoid wrapping the rst thread or two to minimize the possibility of getting a piece of shredded tape into the ow stream. When changing ttings,

always clean any tape or debris from the port threads.

It is also recommended that a 20 micron lter be installed upstream of meters with full scale ranges of 1(S)LPM or less and a 50 micron lter be installed upstream of meters with full scale ranges above 1(S)LPM.

Mounting

All M or V Series Gas Flow Meters have mounting holes for convenient mounting to at panels. These

meters are position insensitive and can be mounted in any orientation. The sizes and dimensions for

the mounting holes are shown on pages 33-35.

Application

Maximum operating line pressure is 145 PSIG (1000 kPa).

Caution: Exceeding the maximum specied line pressure may cause permanent damage to the

solid-state differential pressure transducer.

If the line pressure is higher than 145 PSIG (1000 kPa), a pressure regulator should be used upstream from the ow meter to reduce the pressure to 145 PSIG (1000 kPa) or less if possible. Although the meter’s operation is uni-directional, reversing the ow direction will inict no damage as long as the maximum specied limits are not exceeded.

Note: Avoid installations (such as snap acting solenoid valves upstream) that apply instantaneous

high pressure to the meter as permanent damage to the differential pressure sensor could result.

This damage is not covered under warranty!

Power and Signal Connections

7 8

1 2

4 5

AC/DC Adapter Jack

Power can be supplied to your M or V Series meter through either the power jack or the 8 pin Mini-DIN

connector as shown in Figure 1. An AC to DC adapter which converts line AC power to DC voltage

between 7 and 30 volts is required to use the power jack. The adapter current should be at least 100mA. The power jack accepts 2.1 mm female power plugs with positive centers. Cables and AC/DC adaptors may purchased from Apex (see Accessories page 42) and are commonly available at local electronics

suppliers. Alternatively, power can be supplied through the Mini-DIN connector as shown below:

Pin Function

1 Inactive or 4-20mA Primary Output Signal Black

3 RS-232 Input Signal Red 4 Analog Input Signal = Remote Tare (Ground to Tare) Orange 5 RS-232 Output Signal Yellow 6 0-5 Vdc (or 0-10 Vdc) Output Signal Green 7 Power In (7-30 Vdc, 100mA) or (15-30Vdc for 4-20mA units) Blue 8 Ground (common for power, communications and signals) Purple

Note: The above pin-out is applicable to all the ow meters and controllers available with the MiniDIN connector. The availability of different output signals depends on the ow meter options ordered.

Underlined Items in the above table are optional congurations that are noted on the unit’s calibration sheet.

Static 5.12 Vdc or Secondary Analog Output (4-20mA, 5Vdc, 10Vdc) or Basic Alarm

4 5

Mini-DIN

cable color

Brown

Figure 1. 8 Pin Mini-DIN Connector

CAUTION:Do not connect power to pins 1 through 6 as permanent damage can occur!

Note: Upon initial review of the pin out diagram in Figure 1, it is common to mistake Pin 2 (labeled

5.12 Vdc Output) as the standard 0-5 Vdc analog output signal! In fact Pin 2 is normally a constant

5.12 Vdc that reects the system bus voltage and can be used as a source for the input signal.

RS-232 Digital Output Signal

If you will be using the RS-232 output signal, it is necessary to connect the RS-232 Output Signal (Pin

5), the RS-232 Input Signal (Pin 3), and Ground (Pin 8) to your computer serial port as shown in Figure

2. Adapter cables are available from the manufacturer or they can be constructed in the eld with parts

from an electronics supply house. In Figure 2, note that the diagrams represent the “port” side of the connections, i.e. the connector on top of the meter and the physical DB-9 serial port on the back of the

computer. The cable ends will be mirror images of the diagram shown in Figure 2. (See page 16 for details on accessing RS-232 output.)

Standard Voltage (0-5 Vdc) Output Signal

All M or V Series ow meters have a 0-5 Vdc (optional 0-10 Vdc) output signal available on Pin 6. This

is generally available in addition to other optionally ordered outputs. This voltage is usually in the range

of 0.010 Vdc for zero ow and 5.0 Vdc for full-scale ow. The output voltage is linear over the entire

range. Ground for this signal is common on Pin 8.

Optional 0-10 Vdc Output Signal

If your meter was ordered with a 0-10 Vdc output signal, it will be available on Pin 6. (See the Calibration Data Sheet that shipped with your meter to determine which output signals were ordered.) This voltage is usually in the range of 0.010 Vdc for zero ow and 10.0 Vdc for full-scale ow. The output voltage is

linear over the entire range. Ground for this signal is common on Pin 8.

Optional Current (4-20 mA) Output Signal

If your meter was ordered with a 4-20 mA current output signal, it will be available on Pin 1. (See the Calibration Data Sheet that shipped with your meter to determine which output signals were ordered.) The current signal is 4 mA at 0 ow and 20 mA at the meter’s full scale ow. The output current is linear over the entire range. Ground for this signal is common on Pin 8. (Current output units require 15-30Vdc power.)

Note: This is a current sourcing device. Do not attempt to connect it to “loop powered” systems.

Optional 2nd Analog Output Signal

You may specify an optional 2nd analog output on Pin 2 at time of order. (See the Calibration Data Sheet that shipped with your meter to determine which output signals were ordered.) This output may be a 0-5 Vdc, 0-10 Vdc, or 4-20 mA analog signal that can represent any measured parameter. With this optional output, a volumetric ow meter could output the volumetric ow rate with a 0-5 Vdc signal (on pin 6) and a 4-20 mA signal (on pin 2), or a mass ow meter could output the mass ow rate (0-5 Vdc on pin 6) and the absolute pressure (0-5 Vdc on pin 2).

Note: This is a current sourcing device. Do not attempt to connect it to “loop powered” systems.

DB-9 Serial Port

5----------Ground--------------------------------------Ground----------8 3----------Transmit------------------------------------Receive---------3 2----------Receive-------------------------------------Transmit--------5

8 Pin Mini-DIN Port

1 2 3 4 5

6 7

8 9

Figure 2. Mini-DIN to DB-9 Connection for RS-232 Signals

Purple (Ground)

Red

Yellow

Unit A

Purple

Red

Yellow

Unit B

Purple

Red

Yellow

Unit C

Female Serial Cable Front

Figure 3. Typical Multiple Device (Addressable) Wiring Conguration

An optional industrial connector is also available:

Pin Function Cable Color

Power In ( + )

2 RS-232 Output Blue 3 RS-232 Input Signal White 4 Remote Tare (Ground to Tare) Green 5 Ground (commom for power,

communications and signals)

6 Signal Out (Voltage or Current as ordered) Brown

Figure 4. Optional Industrial Connector

Note: The above pin-out is applicable to all the ow meters and controllers ordered with the industrial connector. The availability of different output signals depends on the ow meter options ordered.

Red

Black

Figure 5. Proper set up for remote tare on meters (Momentarily ground Pin 4 to Tare)

M Series Mass Flow Meter Operation

The M Series Mass Flow Meter provides a multitude of useful ow data in one simple, rugged device. The M Series can have several display “modes” depending on how the device is ordered. All M Series meters have a default Main Mode, Select Menu Mode, a Gas Select Mode (the Gas Select Mode may not be available on meters calibrated for a custom gas or blend), a Communication Select Mode and a Manufacturer Data Mode. (In addition, your device may have been ordered with a Totaliizing Mode, page 36.) The device defaults to Main Mode as soon as power is applied to the meter.

Main Mode

The main mode display defaults on power up with the mass ow on the primary display. The following

parameters are displayed in the main mode as shown in Figure 6.

PSIA oC Tare

+13.49 +22.73

SCCM Air

+0.000 +0.000

Volume Mass Main

MASS

Figure 6. Main Mode Display, M Series Flow Meter

The “MODE” button in the lower right hand corner toggles the display between Main Display and the

Select Menu Display.

Tare – Pushing the dynamically labeled “Tare” button in the upper right hand corner tares the ow meter and provides it with a reference point for zero ow. This is a simple but important step in obtaining accurate measurements. It is good practice to “zero” the ow meter each time it is powered up. If the ow reading varies signicantly from zero after an initial tare, give the unit a minute or so to warm up

and re-zero it.

If possible, zero the unit near the expected operating pressure by positively blocking the ow downstream of the ow meter prior to pushing the “Tare” button. Zeroing the unit while there is any ow will directly affect the accuracy by providing a false zero point. If in doubt about whether a zero ow condition exists,

remove the unit from the line and positively block both ports before pressing the “Tare” button. If the unit

reads a signicant negative value when removed from the line and blocked, it is a good indication that it was given a false zero. It is better to zero the unit at atmospheric pressure and a conrmed no ow

conditions than to give it a false zero under line pressure.

Note: A remote tare can be achieved by momentarily grounding pin 4 to tare as shown in Figure 5

on page 9.

Gas Absolute Pressure: The M Series ow meters utilize an absolute pressure sensor to measure the line pressure of the gas ow being monitored. This sensor references hard vacuum and accurately

reads line pressure both above and below local atmospheric pressure. This parameter is located in

the upper left corner of the display under the dynamic label “PSIA”. This parameter can be moved to the primary display by pushing the button just above the dynamic label (top left). The engineering unit associated with absolute pressure is pounds per square inch absolute (PSIA). This can be converted to gage pressure (psig = the reading obtained by a pressure gauge that reads zero at atmospheric pressure) by simply subtracting local atmospheric pressure from the absolute pressure reading:

PSIG = PSIA – (Local Atmospheric Pressure)

The ow meters use the absolute pressure of the gas in the calculation of the mass ow rate. For working in metric units, note that 1 PSI = 6.89 kPa.

Gas Temperature: The M Series ow meters also utilize a temperature sensor to measure the line temperature of the gas ow being monitored. The temperature is displayed in engineering units of degrees Celsius (°C). The ow meters use the temperature of the gas in the calculation of the mass ow rate. This parameter is located in the upper middle portion of the display under “°C”. This parameter can be moved to the primary display by pushing the top center button above “°C”.

Volumetric Flow Rate: The volumetric ow rate is determined using the Flow Measurement Operating

Principle described elsewhere in this manual. This parameter is located in the lower left corner of the

display over “Volume”. This parameter can be moved to the primary display by pushing the “Volume” button (lower left). In order to get an accurate volumetric ow rate, the gas being measured must be selected (see Gas Select Mode). This is important because the device calculates the ow rate based on

the viscosity of the gas at the measured temperature. If the gas being measured is not what is selected,

an incorrect value for the viscosity of the gas will be used in the calculation of ow, and the resulting

output will be inaccurate in direct proportion to the ratio between the two gases viscosities.

Mass Flow Rate: The mass ow rate is the volumetric ow rate corrected to a standard temperature and pressure (typically 14.696 psia and 25°C). This parameter is located in the lower middle portion

of the display over “Mass”. This parameter can be moved to the primary display by pushing the button

located below “Mass” (bottom center). The meter uses the measured temperature and the measured absolute pressure to calculate what the ow rate would be if the gas pressure was at 1 atmosphere and the gas temperature was 25°C. This allows a solid reference point for comparing one ow to another.

Flashing Error Message: Our ow meters and controllers display an error message (MOV = mass overrange, VOV = volumetric overrange, POV = pressure overrange, TOV = temperature overrange) when a measured parameter exceeds the range of the sensors in the device. When any item ashes on the display, neither the ashing parameter nor the mass ow measurement is accurate. Reducing the value of the ashing parameter to within specied limits will return the unit to normal operation and

accuracy.

Select Menu Mode

Pushing “Mode” once will bring up the “Select Menu” display. Push the button nearest your selection to go to the corresponding display. Push “Mode” again to return to the Main Mode display. (Note: If your

meter was ordered with Totalizing Mode option (page 36), pushing the “Mode” button once will bring up

the “Totalizing Mode” display. Pushing “Mode” a second time will bring up the “Select Menu” display.)

Gas

Select

SELECT

Comm. Mfg.

RS-232 Data Menu

Figure 7. Select Menu Display

Gas Select Mode

The gas select mode is accessed by pressing the button above “Gas Select” on the Select Menu

display. The display will appear as shown in Figure 8 below.

PgUP PgDWN Main

H2 Hydrogen He Helium >N2 Nitrogen N2O Nitrous Oxide Ne Neon O2 Oxygen UP DOWN Gas

Figure 8. Gas Select Display

The selected gas is displayed on the default main mode display as shown in Figure 6, and is indicated

by the arrow in the Gas Select Mode display in Figure 8. To change the selected gas, use the buttons under “UP” and “DOWN” or above “PgUP” and “PgDWN” to position the arrow in front of the desired

gas. When the mode is cycled back to the Main Mode, the selected gas will be displayed on the main

display. (Note: Gas Select Mode may not be available for units ordered for use with a custom gas or

blend.)

Communication Select Mode

The Communication Select mode is accessed by pressing the button below “Comm. RS-232” on the Select Menu display. The screen will appear as shown in Figure 9 below.

Select Main

Unit ID (A).....A

Baud (19200)....19200

Data Rate......Fast

Comm.

UP DOWN RS-232

Figure 9. Communication Select Display

Unit ID – Valid unit identiers are letters A-Z and @ (see Note below). This identier allows the user to assign a unique address to each device so that multiple units can be connected to a single RS-232 port on a computer. The Communication Select Mode allows you to view and/or change a unit’s unique address. To change the unit ID address, press the “Select” button in the upper left corner of the display until the cursor arrow is in front of the word “Unit ID”. Then, using the UP and DOWN buttons at the

bottom of the display, change the unit ID to the desired letter. Any ID change will take effect when the Communication Select Screen is exited by pushing the MODE or Main button.

Note: When the symbol @ is selected as the unit ID, the device will go into streaming mode when the Communication Select Mode is exited by pushing the MODE or Main button. See the RS-232

Communications chapter in this manual for information about the streaming mode.

Baud – The baud rate (bits per second) determines the rate at which data is passed back and forth

between the instrument and the computer. Both devices must send/receive at the same baud rate in

order for the devices to communicate via RS-232. The default baud rate for these devices is 19200 baud, sometimes referred to as 19.2K baud. To change the baud rate in the Communication Select Mode, press the “Select” button in the upper left corner of the display until the cursor arrow is in front of the word “Baud”. Then, using the UP and DOWN buttons at the bottom of the display, select the required baud rate to match your computer or PLC. The choices are 38400, 19200, 9600, or 2400 baud.

Any baud rate change will not take effect until power to the unit is cycled.

Data Rate – Changing the Data Rate affects the rate at which the instrument dumps its data in the

streaming mode. Slow is ½ the Fast rate. The speed of the Fast rate is determined by the selected

baud rate. It is sometimes desirable to reduce the data rate if the communication speed bogs down

the computer’s processor (as is not uncommon in older laptops), or to reduce the size of data les collected in the streaming mode. To change the data rate in the Communication Select Mode, press the “Select” button in the upper left corner of the display until the cursor arrow is in front of the word “Data Rate”. Then, using the UP and DOWN buttons at the bottom of the display, select either Fast or Slow.

Any data rate change will be effective immediately upon changing the value between Fast and Slow.

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