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Rapidlogger User Manual (English)

       

3    Advanced User Section

3.1   Using Sensors with Rapidlogger

This section describes the use and setup of various types of sensors with the Rapidlogger system.  The example calculations are meant for advanced users that have a good understanding of sensor setup and associated calculations.  If there is any doubt please contact the factory for support on calculating the scale and offset factors for a specific type of sensor.

Pressure Transducer

Pressure is measured by means of a pressure transducer.  In general two types of pressure transducers are used in the oilfield:  Hammer union type and threaded type.  Both type of pressure transducers are analog sensors.  Their output can be in the form of a current, a voltage or a millivolt signal.  In all cases the analog output is proportional to the pressure that is applied to the pressure transducer.  The output of a current type pressure transducer ranges from 4 to 20 milliamperes.  These are the most common type of pressure transducers used in the oilfield and are sometimes called current loop, 4-20mA or milliampere sensors, these sensors can be directly connected to one of the milliampere inputs of the Rapidlogger.  The output of a voltage type pressure sensor can range from 0-10Volts and this type of sensor can be attached to a Rapidlogger unit's analog input if they have been configured at the factory for Voltage input.  A millivolt type pressure sensor can only be connected to the Rapidlogger analog inputs via a signal conditioner or current amplifier.

Typical Oilwell Pressure Sensor                                 Wired Oilfield Pressure Sensor

Analog sensors such as pressure transducers can be interfaced to one of the system's four high resolution analog inputs.  All four analog inputs support 4-20mA signal inputs and both 2 and 3 wire sensors.  The scale and offset values for a 15,000 psi pressure transducer can be calculated as follows.

         Rapidlogger mA input setup

         0-20mA full range = 65535 (A/D counts)

         4-20mA scaled range = 52428 (A/D counts)

         0-4mA scaled range = 13107 (A/D counts)

         Scale Factor = 15000 (psi) / 52428 (AtoD counts) = 0.2861066 (psi/count)

         Offset Value = 0.2861066 x 13107 = -3750 (psi)

Proximity Sensors

Pump stroke sensors are proximity switches that sense the rotation of some moving part of a pump.  Both 2 and 3 wire type proximity switches ranging from 12-24V can be interfaced to the Rapidlogger.  Proximity sensors or stroke counters as they are sometimes called can be one three common types.  The most commonly used type of proximity sensor is in inductive proximity switch that generates a signal every time a piece of metal is within range.  Other type of sensors can be a reed switch that causes a switch closure every time it is exposed to a magnet.  The Rapidlogger can accommodate most types of DC proximity switches (Pulse type, open collector type and dry contact/switch closure type).

Proximity Sensors

Software setup for all of these sensors would be the same but they may have to be wired differently based on their manufacturer’s documentation.  Two of the Rapidlogger frequency inputs (F1, and F2) are meant strictly for proximity switches and can accommodate both square wave and sinusoidal type inputs from -24 to 24V.  The other two frequency inputs (Q1A, and Q2A) are shared between the frequency input and quadrature inputs and can only accommodate positive DC square wave inputs (such as the ones generated by the majority of proximity sensors.  The usage of these two inputs (Q1A, and Q2A) can be configured from the front panel to be for frequency or Quadrature.  Each of the four frequency inputs is automatically totalized by the system and the totals are available to be displayed and can be recorded.  The conversion factor for a pump equipped with a 2000 pulse per barrel proximity switch can be calculated as follows.

            Rapidlogger total counts input setup

            Pulses per barrel = 2000 pulses/barrel

            Scale Factor = 1 / 2000 pulses/barrel

            Offset Value = 0 barrels

            Rapidlogger rate setup (for barrels / minute)

            Internal rate time base = 1 seconds

            External rate time base = 1 minute = 60 seconds

            Pulses per barrel = 2000 pulses / barrel

            Internal to external rate conversion = 60/1 = 60

            Scale Factor = 1 / 2000 x 60 = 0.03

            Offset Value = 0 barrels / minute

 

 

Depth Encoder

A depth encoder is used on slickline, electric line, and coiled tubing operations to measure the length or depth of wire or pipe in the hole. This is usually done by running a friction wheel on the wire or pipe. The friction wheel is connected to the shaft of the depth encoder. A depth encoder is shown below along with one with a slickline depth friction wheel adapter attached.

Depth Encoder                                       Depth Encoder Hardware

The output of a depth encoder is in the form of two sets of pulse signals (usually labeled A and B signals) that are 90 degrees out of phase with each other.  These are called quadrature pulses and the encoders are called quadrature encoders.  The output pulses from a depth encoder are usually 5Volt however some types of depth encoders have 12 volt output pulses.  The Rapidlogger can be interfaced with up to two quadrature encoders with output pulses ranging from 5 to 24 Volts.  In order to calculate the scaling factor of a depth encoder some information about its mounting scheme is also required.  A depth encoder attached to the friction wheel on a slickline unit is shown below.  

Mounted Depth Encoder

In the previous diagram the depth encoder is connected to the friction wheel through a 1:1 ratio.  So for each turn of the encoder slickline equal to one circumference of the wheel will pass through. Different depth encoders can have different number of pulses per revolution.  The scale factor for a 300 pulse/revolution depth encoder mounted on a 2 foot circumference wheel can be calculated as follows.

      Rapidlogger total quadrature input setup

      Pulses per revolution = 300 (pulses / revolution)

      Pulses per foot = 300 (pulses) / 2 (ft) = 150 (pulses per foot)

      Scale Factor = 1 / 150 (feet / pulse) = 0.0066667

      Offset Value = 0 (feet)

      Rapidlogger quadrature rate setup

      Internal rate time base = 1 seconds

      External rate time base = 1 minute = 60 seconds

      Internal to external rate conversion = 60/1 = 60

      Scale Factor = 1 / 150 x 60 (feet / pulse/minute) = .4000

      Offset Value = 0 (feet/minute)

If the wheel diameter is used to calculate the wheel circumference rather than a calibration run in the shop or yard, then the diameter of the slickline should also be taken into account in the calculation of the circumference.

      Rapidlogger slickline friction wheel circumference calculation

      Diameter of the wheel at bottom of slickline groove in wheel = 1.0 ft

      Diameter of the slickline = 0.125 inch = 0.0104167 ft

      Effective diameter of the wheel = 1 ft +2 x (0.0104167 / 2) ft

      Effective diameter of the wheel = 1.0104167ft

      Circumference of wheel = Pi  x  diameter = p x diameter = 3.1743176

      Rapidlogger total quadrature input setup

      Internal to external rate conversion = 60/1 = 60

      Pulses per revolution = 300 (pulses / revolution)

      Pulses per foot = 300 / 3.1743176 = 94.5085 (pulses per foot)

      Scale Factor = 1 / 94.5085 (feet / pulse) = 0.01058106

      Offset Value = 0 (feet/minute)

 

      Rapidlogger quadrature rate setup

      Scale Factor = 1 / 94.5085 x 60 (feet / pulse/minute) = 0.63486352

      Offset Value = 0 (feet/minute)

 

 

Load Cell

Tension and compression on slickline, wireline and coiled tubing units are measured by means of load cells.  Load cells come in many different shapes and sizes.  Two different types of load cells are shown below.  The output of load cells can be in the form of a current, a voltage or a millivolt signal.  In all cases, the analog output is proportional to the tension or compression that is applied to the load cell. 

Load Cell                Load Cell Monitoring Software

An analog load cell can be connected to any of the four milliamp inputs of the Rapidlogger.  The scale and offset values for a 50000 lbs compression only load cell can be calculated as follows.

      Rapidlogger mA input setup

      0-20mA full range = 65535 (A/D counts)

      4-20mA scaled range = 52428 (A/D counts)

      0-4mA scaled range = 13107 (A/D counts)

      Scale Factor = 50000 (lbs) / 52428 (AtoD counts) = 0.95369(lbs/count)

      Offset Value = 0.95369 x 13107 = -12500 (lbs)

The scale and offset values for a 50000 lbs tension/compression load cell can be calculated as follows.

      Rapidlogger mA input setup

      0-20mA full range = 65535 (A/D counts)

      4-20mA scaled range = 52428 (A/D counts)

      Zero for a tension compression cell would be at 12mA or 39321 counts

      Scale Factor = (50000+50000) (lbs) / 52428 (counts) = 1.907378 (lbs/count)

      Offset Value = 0.1907378 x 39321 = -75000 (lbs)

Wellhead Loadcell Systems

For slickline and electric line work the load cell is often attached to the bottom sheave at the wellhead.  In such an installation the load cell sees a different load than the tension in the line.  This changes the calculation for the scale factor and the offset of the load cell.  This type of an installation is shown earlier in this section.  If the wireline angle over the bottom sheave is 90 degrees then the scale and offset values for a 5000 lbs tension load cell installed on a wireline or slickline unit on the sheave shackle can be calculated as follows.

      Rapidlogger mA input setup for sheave wheel attachment

      0-20mA full range = 65535 (A/D counts)

      4-20mA scaled range = 52428 (A/D counts)

      0-4mA scaled range = 13107 (A/D counts)

      Wireline Angle on sheave = 90 degrees

      Sheave factor = 2 x cos(90 / 2) degrees = 2 x 0.707106 = 1.4142135

      Scale Factor = Loadcell capacity / Sheave factor / 4-20mA scaled range

      Scale Factor = 5000 / 1.4142135  / 52428 = 0.0674359866 (lbs/count)

      Offset Value = 0.0674359866 x 13107 = -883.883 (lbs)

The wireline angle over the sheave is not always 90 degrees.  In the following calculation example the scale factor and offset for a 2000 lbs load cell installed on a sheave with a wireline angle of 95 degrees is calculated. 

      Rapidlogger mA input setup for sheave wheel attachment

      0-20mA full range = 65535 (A/D counts)

      4-20mA scaled range = 52428 (A/D counts)

      0-4mA scaled range = 13107 (A/D counts)

      Wireline Angle on sheave = 95 degrees

      Sheave factor = 2 x cos(95 / 2) degrees = 2 x 0.6755902 = 1.3511804152

      Scale Factor = Load cell capacity / Sheave factor / 4-20mA scaled range

      Scale Factor = 2000 / 1.3511804152 / 52428 = 0.0282327621 (lbs/count)

      Offset Value = 0.0282327621 x 13107 = -370.04 (lbs)

Coriolis Flowmeter and Densitometer

Many modern cement units are equipped with a Coriolis-type densitometer (Micro Motion, Endress+Hauser, etc).  These densitometers can measure the flow-rate, volume, and density of the treatment fluid.  The output from the densitometers is generally in the form of an analog output for density and a frequency output for the flow rate.  These signals can be interfaced to the Rapidlogger unit and the data can be displayed and recorded.  The milliampere outputs from the flowmeter transmitter unit can be connected to one of the milliampere inputs, and the frequency outputs from the flowmeter can be connected to one of the frequency inputs of the Rapidlogger.  The flow and density meters from Micro Motion and Endress+Hauser allow the scaling of the output signal.  These scale factors are configurable on the output transmitters made by the manufacturers.  This is usually accomplished by a PC based setup program that is provided by the manufacturer of the flowmeter.  The output scale factor must be known in order to properly interface the flow and density meters to the Rapidlogger. 

Coriolis Flowmeter                       Coriolis Flowmeter Hardware

Once these scale factors are known, the analog and frequency scale and offset settings of the relevant Rapidlogger inputs can be calculated as shown in the previous sections.  Generally the flowmeter output the density on a milliamp output and the flow rate is transmitted on a frequency output from the flowmeter transmitter.  Contact the factory for more support on interfacing flowmeters to the Rapidlogger system.

3.2   Installing and removing SD Memory card

The SD Memory card (5) installed in the Rapidlogger unit records all job data when it is powered on.  The operator does not need to do anything to start the job recording, other than turning the unit on.  In normal use the data is retrieved from the SD Memory card via Ethernet link using the supplied PC programs “Rapidlogger” or the “RapidloggerFile”.  As more and more data is recorded on the SD Memory card it starts getting full.  It is strongly recommended that the SD Memory card be erased or formatted every few weeks to prevent data corruption.  This can be done by using the “RapidloggerFile” program or from the front panel keypad of the (Press F6, F6, F6, F5). Please make sure all old job data has been transferred from the SD Card to the PC.

WARNING:  The SD card on the Rapidlogger can be corrupted by repeated improper power shutdowns and fluctuations.  The user should download all important job data after every job.  The SD card should be formatted / erased either from the front panel or by using the Rapid VU program every few jobs (10 - 15 jobs) after they have been downloaded.

 

 


3.3   Components of the Rapidlogger System

The various components of the Rapidlogger system are shown in the diagram below.

 


Components of the Rapidlogger System

 

 1)       LCD screen     

 2)       Main board

 3)       Power connector

 4)       Serial port connector

 5)       SD Card

 6)       SD Card connector

 7)       Ethernet Connector

 8)       Clock backup battery

 9)       Grounding connector

10)       Wiring terminal

11)       Mounting plate

12)       CPU Module

13)       Field Replaceable 1 Amp Fuse

 

 

3.4   Interfacing Rapidlogger to a PC via Ethernet

The Rapidlogger is equipped with a weatherproof Ethernet connector.  If a cable is installed in this connector and connected to a network port, the Rapidlogger can communicate with a PC computer.  Most Ethernet cables that are used are wired straight through and are meant to attach a device to an Ethernet Hub or Switch.  This is the type of cable that is installed on the Rapidlogger.  The second type of Ethernet cables that are used are wired in a crossover manner and are meant to connect two devices to each other without the need for a hub.  A short crossover patch is supplied with the Rapidlogger and can be installed in between the Ethernet socket (7) and cable connector. 

Thus if the installation requires the Rapidlogger to communicate with a PC through a Hub/Switch as in the majority of the cases, then the Ethernet cable should be used without any changes. If, however the installation requires the Rapidlogger to communicate with a PC without a Hub/Switch then the crossover patch should be installed inside the Rapidlogger unit.

The second part of communicating with a PC is setting up of the correct IP address, gateway address and network mask.  There are two types of address setup mechanisms, automatic/dynamic/DHCP and static.  The Rapidlogger unit uses static IP addresses.  The current IP address and gateway address setup in the unit is displayed on the screen on the bottom left and bottom right of the screen for a few seconds after the unit is powered up.  Both or these are numbers are a sequence of four three digit numbers of the form (192.168.000.005).  In order for the Rapidlogger to communicate properly with a PC over the Ethernet connection, the PC and Rapidlogger should have compatible IP addresses that are within the same subnet.  If the user is unfamiliar with IP addresses then it is recommended that they use the following. 

 

PC / Laptop       IP: 192.168.000.001              Gateway: 192.168.000.001    Netmask: 255.255.255.000

Rapidlogger      IP: 192.168.000.005              Gateway: 192.168.000.001    Netmask: 255.255.255.000

IP settings on a PC are done from the Windows control panel in the IP setting field within the properties of the LAN Connection Dialog box.  On the Rapidlogger these settings are done from the front panel keypad.  Press F6, F6, F1 and then enter the IP address, Gateway and Netmask when prompted on the screen.  Perform a power cycle to verify and activate the IP address from the LCD screen.  The default IP address of 192.168.000.005 is setup in the system at the factory.  This is also the IP address that the system goes back to whenever a factory reset is done.  Advanced users should select and utilize the IP addresses appropriate for their network. 

Once the IP addresses are setup then the PC and the Rapidlogger are able to communicate with each other.  Proper communication can be verified by performing a PING from the PC to the Rapidlogger IP address.  Do note that some PC firewall programs block Ethernet communication that they are not familiar with.  If you have such a firewall running on your PC then you may either need to disable it or specifically setup it up to allow full two way communication to the Rapidlogger IP Address. 

3.5   Sensor Input Diagnostics

The Rapidlogger Unit has a built in diagnostics mode in which the raw sensor inputs can be viewed to ease troubleshooting.  The diagnostics mode for analog sensors can be accessed from the front panel keypad (Press F6, F6, F6, F1).  The diagnostics mode for frequency sensors can be accessed from the front panel keypad (Press F6, F6, F6, F2).  In each case a screen appears on the LCD that displays the various sensor values.

3.6   Editing Input Variables

All of the Rapidlogger data is based on calculations performed on input data.  The results of the calculations are stored in the system variables.  The settings of the input variables can be viewed and edited from the front panel and by using the PC program Rapidlogger Utility. 

In order to view a system variable, select the view option (Press F6, F6, F4, F3) and then enter the variable number to view.  To edit a system variable, select the view option (Press F6, F6, F4, F4) and then enter the variable number to edit.  The system will prompt you with the current value of each of the settings for that particular variable and then allow you to enter a new value.  For any values that need to remain unchanged press F6 and the system will skip to the next value.  Editing system variables is a feature that should only be done by advanced users and then too it should be done by using the Rapidlogger Utility. 

3.7   Modbus Communication

The Rapidlogger unit is capable of communicating with other third party devices HMIs, SCADA, systems, and PLCs using Modbus.  The Modbus protocol is a messaging structure, widely used to establish master-slave communication between intelligent devices.  A Modbus message sent from a master to a slave contains the address of the slave, the 'command' (e.g. 'read register' or 'write register'), the data, and a check sum.  Since the Modbus protocol is just a messaging structure, it is independent of the underlying physical layer.  On the Rapidlogger Unit it is implemented on both RS232, and Ethernet and it can use both the Modbus-TCP and Modbus-RTU protocols.  The Rapidlogger can operate in both Modbus master and slave modes. 

The Rapidlogger unit has 16 Modbus input registers for use in the slave mode.  Each of these input registers is 2 bytes wide and can be used on their own as short integers or combined in pairs to form 4 byte floating point value registers.  In slave mode the Rapidlogger unit allows an external Modbus master device to read the values in its input registers. The following table shows the Rapidlogger Modbus register layout for slave mode of operation.

Modbus Slave Registers (Data Output Only)

 

Modbus Register

Register Type

Register Type

R/W

Function

Description

1

Unsigned Int

Float

Read

04

Input Register

2

Unsigned Int

 

Read

04

Input Register

3

Unsigned Int

Float

Read

04

Input Register

4

Unsigned Int

 

Read

04

Input Register

5

Unsigned Int

Float

Read

04

Input Register

6

Unsigned Int

 

Read

04

Input Register

7

Unsigned Int

Float

Read

04

Input Register

8

Unsigned Int

 

Read

04

Input Register

9

Unsigned Int

Float

Read

04

Input Register

10

Unsigned Int

 

Read

04

Input Register

11

Unsigned Int

Float

Read

04

Input Register

12

Unsigned Int

 

Read

04

Input Register

13

Unsigned Int

Float

Read

04

Input Register

14

Unsigned Int

 

Read

04

Input Register

15

Unsigned Int

Float

Read

04

Input Register

16

Unsigned Int

 

Read

04

Input Register

The Rapidlogger unit also has 16 Modbus internal registers for use in the master mode.  Each of these input registers is 2 bytes wide and can be used on their own as short integers or combined in pairs to form 4 byte floating point value registers.  In master mode the Rapidlogger unit polls an external slave device and stores the values from the slaves input registers into its internal holding registers.  The following table shows the Rapidlogger Modbus register layout for master mode of operation.  The input registers on the external slave device that the Rapidlogger reads need not be consecutive.

Modbus Master Registers (Data Input Only)

 

Modbus Register

Register Type

Register Type

R/W

Function

Description

17

Unsigned Int

Float

Write

04

Input Register

18

Unsigned Int

 

Write

04

Input Register

19

Unsigned Int

Float

Write

04

Input Register

20

Unsigned Int

 

Write

04

Input Register

21

Unsigned Int

Float

Write

04

Input Register

22

Unsigned Int

 

Write

04

Input Register

23

Unsigned Int

Float

Write

04

Input Register

24

Unsigned Int

 

Write

04

Input Register

25

Unsigned Int

Float

Write

04

Input Register

26

Unsigned Int

 

Write

04

Input Register

27

Unsigned Int

Float

Write

04

Input Register

28

Unsigned Int

 

Write

04

Input Register

29

Unsigned Int

Float

Write

04

Input Register

30

Unsigned Int

 

Write

04

Input Register

31

Unsigned Int

Float

Write

04

Input Register

32

Unsigned Int

 

Write

04

Input Register

The Modbus settings can be adjusted using the Rapidlogger Utility program.  Familiarity with the Modbus protocol is required to correctly setup the various Modbus related settings.  The following picture shows the setup screen for adjusting various Modbus settings.

Rapidlogger Utility Program Setup Screen

From the Modbus settings selection the user can select the Modbus device type or simply disable Modbus communication.  The Modbus local slave ID is the Modbus device number that the Rapidlogger Unit appears as to a Modbus master.  While the Remote slave ID is the Modbus device number that the Rapidlogger Unit needs to poll to obtain Modbus data from.  The local and remote slave IDs are generally only used when Modbus is on a serial communication protocol.  When using Modbus TCP the IDs are generally ignored.  The setting for Modbus remote slave TCPIP address is used to tell the Rapidlogger the IP address of the remote slave that it should poll to obtain the Modbus data.  When using the Rapidlogger as a Modbus TCP slave the IP address of the Rapidlogger unit should be entered in to the remote Modbus master's settings area.  All Modbus polling on the Rapidlogger is limited to a 1Hz acquisition rate.

Continue to Section 4.0 Installation Section

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