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GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic
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FUSION-8808; No. of Pages 5
Fusion Engineering and Design xxx (2016) xxx–xxx
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GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic Kiran Patel ∗ , Vishal Pillai, Neha Singh, Vishnu Chaudhary, Jinto Thomas, Ajai Kumar Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428, India
a r t i c l e
i n f o
Article history: Received 15 June 2015 Received in revised form 24 May 2016 Accepted 14 June 2016 Available online xxx Keywords: Thomson Scattering Data acquisition (DAQ) LabVIEW CAMAC GPIB
a b s t r a c t The ADITYA Thomson Scattering Diagnostic is a single point Ruby laser based system with a spectrometer for spectral dispersion and photomultiplier tubes for the detection of scattered light. The system uses CAMAC (Computer Automated Measurement And Control) based control and data acquisition system, which synchronizes the Ruby laser, detectors and the digitizer. Previously used serial based CAMAC controller is upgraded to GPIB (General Purpose Interface Bus) based CAMAC controller for configuration and data transfer. The communication protocols for different instruments are converted to a single GPIB based for better interface. The entire control and data acquisition program is developed on LabVIEW platform for versatile operation of diagnostics with improved user friendly GUI (Graphical User Interfaces) and allows user to remotely update the laser firing time with respect to the plasma shot. The software is in handshake with the Tokamak main control program through network to minimize manual interventions for the operation of the diagnostics. The upgraded system improved the performance of the diagnostics in comparison to earlier in terms of better data transmission rate, easy to maintain and program is upgradable. © 2016 Elsevier B.V. All rights reserved.
1. Introduction ADITYA is a medium sized Tokamak with major radius (R) 75 cm and minor radius (a) 25 cm. The plasma duration and current are around 200 msec and 250 kA, respectively. ADITYA Thomson Scattering (TS) is the main diagnostic for the measurement of plasma temperature and density profile. The control and data acquisition of Thomson Scattering Diagnostic [1–7] system consists of a serial based CAMAC (Computer Automated Measurement And Control) Controller for control and digitization of the analog signal. The controller is remotely controlled from control room using CVI based program. The available analog signals were acquired using a digital oscilloscope (Tektronix make DSO-754) for acquiring reference signals from the Photomultiplier tubes (PMT) and Photodiodes (PD) for accurately synchronising the timing signals. The DSO communicates to the computer through GPIB bus. The DSO and CAMAC controller use different communication protocols (serial and GPIB) for the control and data monitoring. The serial CAMAC controller has a very slow data transfer rate. Different instruments having different communication protocols make the operation difficult and tedious when operated synchronously for any diagnostics. To avoid this problem we opted to choose a common high speed
∗ Corresponding author. E-mail address: [email protected] (K. Patel).
communication protocol for all the instruments involved in the instrumentation. The GPIB communication has come as a solution to meet these requirements as all the instruments except the crate module have the GPIB communication ports. The serial CAMAC controller has been replaced with a GPIB crate controller and appropriate driver software developed in LabVIEW for each CAMAC modules. In this article, we describe the up gradation of Thomson Scattering System using GPIB based CAMAC crate Controller [8] for controlling different modules like Dual GATE generator [9], Charge generator [10], Analog to Digital converter [11], Pulse delay generator (Sension make 1351) and Amplifier module (Lecroy make 613A). The developed Graphical User Interfaces (GUI) for controlling and synchronising the instruments and acquiring the data has significantly improved the ease in working with the diagnostics. It also helped in remotely configuring the system for meeting the timing adjustments of Thomson Scattering System in synchronisation with the main control network of ADITYA. 2. ADITYA Thomson Scattering System The TS diagnostic installed on the ADITYA Tokamak is used to measure electron density (ne ) and electron temperature (Te ) at a single spatial point at a given time during the plasma shot. Fig. 1 shows schematic view of the TS system installed in ADITYA Tokamak. The TS system has a Ruby laser with 10 J of energy with 20 ns
http://dx.doi.org/10.1016/j.fusengdes.2016.06.021 0920-3796/© 2016 Elsevier B.V. All rights reserved.
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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Fig. 1. Schematic view of TS system on ADITYA Tokamak.
Fig. 2. Schematic layout of the ADITYA TS Data Acquisition system.
pulse width. The laser passes vertically through the tokomak from bottom to top and the scattered photons are collected using an imaging lens system. A one meter spectrometer disperses the scattered light to an array of fibers positioned at the exit plane for 2 nm spectral width on each fiber. Other end of the fibers are coupled to high gain photo multiplier tube (RCA make C31034) kept inside a complete tight shielding housing. The glass windows of the PMTs are AR coated to insure maximum transmission. The breeder circuit for all the PMTs are for the fast pulse response application [12].
3. Instrumentation and synchronisation A LabVIEW [13] based instrumentation program is developed for instrumentation and synchronisation of the system hardware components. The program initializes and configures different modules to default conditions. The entire CAMAC module is controlled by CAMAC Crate controller (Kinetic System make KS3988) which supports 8 bit, 16 bit or 24 bit data transfer. Fig. 2 shows the schematic layout of the data acquisition system for ADITYA TS system.
The CAMAC controller is configured for 24 bit data width with enable and single transfer modes. After initializing controller module, the program initializes 2323A LeCroy Dual gate generator, 1351 Pulse delay generator, 2249 W LeCroy Charge- Digital converter (CDC), DAQ Pad (6015) module. LeCroy’s CAMAC Model 2323 is a fully programmable pulse generator with adjustable delay. It is a double width, two channel CAMAC module. Its gate duration is programmable in a range of 100 nsec to 10 s, covering a dynamic range of eight orders of magnitude. The Model 2323 offers excellent stability and jitter properties with 0.2% of full scale accuracy in the gate setting. The unit offers NIM outputs, equal in duration of the selected gate width. The gate duration and width of the delayed output are programmable under CAMAC control. Each of the two channels may be set independently. All values which are loaded into the Model 2323 may also be read back via CAMAC. Pulse delay generator 1351 CAMAC module is used for generating required time delay for firing the laser so that the measurement timing may be changed externally. 1351 is a single width module which provides four output pulses of variable pulse width and delay from a single
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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Fig. 3. TSS control and data acquisition system layout.
Fig. 4. GUI for ADITYA TSD.
trigger input. The pulses have guaranteed amplitude of 5 V and a leading edge rise time better than 3 ns. This module can be operated with internal 100 MHz crystal controlled clock or with an external clock. External clock mode can be used to phase lock the output pulse to other instruments like laser and DAQ systems. This module provides five timing ranges, having time period of 10 ns, 100 ns, 1 s, 10 s and 100 s. Appropriate delays are programmed via 12 bit registers where the 10 ns basic period allows delay between 10 ns and 40.96 s. The widths of all pulses are equal and set by an eight bit register. The Charge to Digital Converter (CDC) module 2249 W generates a digital number proportional to the input
charge. The Model 2249 W is a 11-bit integrating-type charge-todigital converter. Energy measurement of the ruby laser is carried out using National Instrument (NI) based USB DAQ Pad 6015. Analog output of a calibrated photo diode is connected to the input of the DAQ. An external trigger pulse from 1351 delay generator triggers the DAQ Pad with sufficient delay to read the laser energy. The overall system layout of the entire control and data acquisition system is shown in Fig. 3. It represents signal flow and connection diagram of the control and DAQ system. The signal from the PMT house is transfer to amplifier module (613A) through delay box for individual delay adjustment. The amplified output of the module is
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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Fig. 5. Calibration results for individual channels of the module.
Fig. 6. Scattered PMT signal acquired during the plasma discharge.
distributed to charge ADC (2249) and digital storage oscilloscope. The CAMAC controller and oscilloscopes are connected through GPIB cable in a daisy chain arrangement. For long distance transmission of the GPIB signal, GPIB to optical converters are used at both ends of the fiber cables.
4. Software program The software of TS diagnostic system has been built on LabVIEW platform. LabVIEW is graphical programming environment which helps engineers/scientists quickly to develop powerful and userfriendly software. A LabVIEW program consists of a numbers of
Virtual Instrument (VI) that consist of front panel and block diagram. Fig. 4 shows the front panel diagram of the ADITYA TS Diagnostic system. To meet the diagnostic data acquisition, the software is divided into two parts. The first part is to configure the diagnostic parameter for the Thomson Scattering and the second is for the measurement related parameters. The program automatically updates the shot number from the ADITYA server using TCP/IP protocol. The entire system becomes ready when the ADITYA Tokamak becomes ready for the next Plasma Discharge. The TS system resets every module and gets ready for the next shot after the main server updates the new shot number. The soft key button “Ready for New
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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5
Fig. 7. Typical temperature measurement for a plasma shot @ 40 ms.
shot” becomes green indicating the user about the event. The second part is to evaluate the experimental results, which include data acquisition, storage and processing. In the acquisition mode, laser is fired at a predefined time interval. The integration time window with predefined width (50–100 ns) is open upon the fast photo diode signal placed adjacent to the laser. The fast photo diode signal is also used as a trigger source for the digitizer module. The NI DAQ pad module records the energy of laser pulse at the same instance. All the acquired data through the charge integrator and the PMT signal traces from the DSO are displayed on the GUI and stored in a computer.
5. Results The developed DAQ system for TS is operational on ADITYA Tokamak. The acquisition time has been reduced significantly (earlier acquisition has transfer rate of around 1.2 KBps, which is very slow in comparison to present 1 MBps). The present GUI developed permits the user to configure the individual parameter of the system for a particular shot. The acquired data are linked to this configuration data, so that the correct information is documented and is available for processing the data. The calibration of the charge integrator module is performed with standard CAMAC charge generator module (Philips 7120). The scattered signal from the spectrometer for different wavelengths is acquired using PMT. Each PMT signal is digitized using CDC module. The CDC module integrates the PMT signal for the duration of the GATE interval and generates digital count corresponding to the area. The calibration result of the individual channels of the module is shown in Fig. 4. The developed instrument program reads digital count from module along with the PMT signal trace on the scope for the reference signal measurement. Fig. 6 shows the scattered PMT signal acquired form the oscilloscope during the plasma discharge. Each PMT signal defines a particular wavelength and signal integration of each channel gives the scattered photons for a particular wavelength. The signal from each channel is used for the calculation of the electron temperature and density. The program generates intensity vs wavelength graph and provides the required slope for the estimate of the temperature (Fig. 5).
Fig. 7 shows electron temperature plot for the plasma discharge @ 40 msec time intervals. The vertical axis is the log scale of the scattered intensity and the horizontal axis the delta lambda square. The temperature calculation is carried out using the method described in reference [14]. 6. Conclusion In this paper, an advanced automatic system based on a CAMAC and LabVIEW programming environment for ATS has been developed. It achieves synchronous control of equipment, real time data acquisition and data display. The upgraded DAQ and control system are improved for the performance of the diagnostics i.e. 1 MBps transmission speed in comparison of the earlier system. The developed system reduces the human error during the operation involving different instruments controlled independently. It also improves the data acquisition and processing capability and accuracy of the experiment. The developed control and data acquisition system has been integrated to ADITYA and successfully operated. Acknowledgments We gratefully acknowledge Dr. H.C. Joshi for fruitful discussion and critically evaluation of the manuscript. References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]
D. Johnson, et al., Rev. Sci. Instrum. 56 (1985) 1015. T.N. Carlstrom, et al., Rev. Sci. Instrum. 63 (10) (1992). K.R. Middaugh et al., General Atomics Report, GA-A23147 (1999). C.M. Greenfield, et al., Rev. Sci. Instrum. 61 (10) (1990). Y.G. Kim, et al., Fusion Eng. Des. 96–97 (2015) 882–886. Francesco Flora, et al., Appl. Opt. 26 (September (18)) (1987). K. Zhai, et al., Rev. Sci. Instrum. 75 (10) (2004). 3988 User Manual Kinetic System Corporation. 2323 User Manual LeCroy Corporation. 7120 User Manual Philips Corporation. 2249 User Manual LeCroy Corporation. C31034 series Photomultipliers Manual, RCA. LabVIEW User Manual, National Instrument Corporation. R. Rajesh, et al., Pramana 55 (2000) 733.
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
ARTICLE IN PRESS
FUSION-8808; No. of Pages 5
Fusion Engineering and Design xxx (2016) xxx–xxx
Contents lists available at ScienceDirect
Fusion Engineering and Design journal homepage: www.elsevier.com/locate/fusengdes
GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic Kiran Patel ∗ , Vishal Pillai, Neha Singh, Vishnu Chaudhary, Jinto Thomas, Ajai Kumar Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428, India
a r t i c l e
i n f o
Article history: Received 15 June 2015 Received in revised form 24 May 2016 Accepted 14 June 2016 Available online xxx Keywords: Thomson Scattering Data acquisition (DAQ) LabVIEW CAMAC GPIB
a b s t r a c t The ADITYA Thomson Scattering Diagnostic is a single point Ruby laser based system with a spectrometer for spectral dispersion and photomultiplier tubes for the detection of scattered light. The system uses CAMAC (Computer Automated Measurement And Control) based control and data acquisition system, which synchronizes the Ruby laser, detectors and the digitizer. Previously used serial based CAMAC controller is upgraded to GPIB (General Purpose Interface Bus) based CAMAC controller for configuration and data transfer. The communication protocols for different instruments are converted to a single GPIB based for better interface. The entire control and data acquisition program is developed on LabVIEW platform for versatile operation of diagnostics with improved user friendly GUI (Graphical User Interfaces) and allows user to remotely update the laser firing time with respect to the plasma shot. The software is in handshake with the Tokamak main control program through network to minimize manual interventions for the operation of the diagnostics. The upgraded system improved the performance of the diagnostics in comparison to earlier in terms of better data transmission rate, easy to maintain and program is upgradable. © 2016 Elsevier B.V. All rights reserved.
1. Introduction ADITYA is a medium sized Tokamak with major radius (R) 75 cm and minor radius (a) 25 cm. The plasma duration and current are around 200 msec and 250 kA, respectively. ADITYA Thomson Scattering (TS) is the main diagnostic for the measurement of plasma temperature and density profile. The control and data acquisition of Thomson Scattering Diagnostic [1–7] system consists of a serial based CAMAC (Computer Automated Measurement And Control) Controller for control and digitization of the analog signal. The controller is remotely controlled from control room using CVI based program. The available analog signals were acquired using a digital oscilloscope (Tektronix make DSO-754) for acquiring reference signals from the Photomultiplier tubes (PMT) and Photodiodes (PD) for accurately synchronising the timing signals. The DSO communicates to the computer through GPIB bus. The DSO and CAMAC controller use different communication protocols (serial and GPIB) for the control and data monitoring. The serial CAMAC controller has a very slow data transfer rate. Different instruments having different communication protocols make the operation difficult and tedious when operated synchronously for any diagnostics. To avoid this problem we opted to choose a common high speed
∗ Corresponding author. E-mail address: [email protected] (K. Patel).
communication protocol for all the instruments involved in the instrumentation. The GPIB communication has come as a solution to meet these requirements as all the instruments except the crate module have the GPIB communication ports. The serial CAMAC controller has been replaced with a GPIB crate controller and appropriate driver software developed in LabVIEW for each CAMAC modules. In this article, we describe the up gradation of Thomson Scattering System using GPIB based CAMAC crate Controller [8] for controlling different modules like Dual GATE generator [9], Charge generator [10], Analog to Digital converter [11], Pulse delay generator (Sension make 1351) and Amplifier module (Lecroy make 613A). The developed Graphical User Interfaces (GUI) for controlling and synchronising the instruments and acquiring the data has significantly improved the ease in working with the diagnostics. It also helped in remotely configuring the system for meeting the timing adjustments of Thomson Scattering System in synchronisation with the main control network of ADITYA. 2. ADITYA Thomson Scattering System The TS diagnostic installed on the ADITYA Tokamak is used to measure electron density (ne ) and electron temperature (Te ) at a single spatial point at a given time during the plasma shot. Fig. 1 shows schematic view of the TS system installed in ADITYA Tokamak. The TS system has a Ruby laser with 10 J of energy with 20 ns
http://dx.doi.org/10.1016/j.fusengdes.2016.06.021 0920-3796/© 2016 Elsevier B.V. All rights reserved.
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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Fig. 1. Schematic view of TS system on ADITYA Tokamak.
Fig. 2. Schematic layout of the ADITYA TS Data Acquisition system.
pulse width. The laser passes vertically through the tokomak from bottom to top and the scattered photons are collected using an imaging lens system. A one meter spectrometer disperses the scattered light to an array of fibers positioned at the exit plane for 2 nm spectral width on each fiber. Other end of the fibers are coupled to high gain photo multiplier tube (RCA make C31034) kept inside a complete tight shielding housing. The glass windows of the PMTs are AR coated to insure maximum transmission. The breeder circuit for all the PMTs are for the fast pulse response application [12].
3. Instrumentation and synchronisation A LabVIEW [13] based instrumentation program is developed for instrumentation and synchronisation of the system hardware components. The program initializes and configures different modules to default conditions. The entire CAMAC module is controlled by CAMAC Crate controller (Kinetic System make KS3988) which supports 8 bit, 16 bit or 24 bit data transfer. Fig. 2 shows the schematic layout of the data acquisition system for ADITYA TS system.
The CAMAC controller is configured for 24 bit data width with enable and single transfer modes. After initializing controller module, the program initializes 2323A LeCroy Dual gate generator, 1351 Pulse delay generator, 2249 W LeCroy Charge- Digital converter (CDC), DAQ Pad (6015) module. LeCroy’s CAMAC Model 2323 is a fully programmable pulse generator with adjustable delay. It is a double width, two channel CAMAC module. Its gate duration is programmable in a range of 100 nsec to 10 s, covering a dynamic range of eight orders of magnitude. The Model 2323 offers excellent stability and jitter properties with 0.2% of full scale accuracy in the gate setting. The unit offers NIM outputs, equal in duration of the selected gate width. The gate duration and width of the delayed output are programmable under CAMAC control. Each of the two channels may be set independently. All values which are loaded into the Model 2323 may also be read back via CAMAC. Pulse delay generator 1351 CAMAC module is used for generating required time delay for firing the laser so that the measurement timing may be changed externally. 1351 is a single width module which provides four output pulses of variable pulse width and delay from a single
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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Fig. 3. TSS control and data acquisition system layout.
Fig. 4. GUI for ADITYA TSD.
trigger input. The pulses have guaranteed amplitude of 5 V and a leading edge rise time better than 3 ns. This module can be operated with internal 100 MHz crystal controlled clock or with an external clock. External clock mode can be used to phase lock the output pulse to other instruments like laser and DAQ systems. This module provides five timing ranges, having time period of 10 ns, 100 ns, 1 s, 10 s and 100 s. Appropriate delays are programmed via 12 bit registers where the 10 ns basic period allows delay between 10 ns and 40.96 s. The widths of all pulses are equal and set by an eight bit register. The Charge to Digital Converter (CDC) module 2249 W generates a digital number proportional to the input
charge. The Model 2249 W is a 11-bit integrating-type charge-todigital converter. Energy measurement of the ruby laser is carried out using National Instrument (NI) based USB DAQ Pad 6015. Analog output of a calibrated photo diode is connected to the input of the DAQ. An external trigger pulse from 1351 delay generator triggers the DAQ Pad with sufficient delay to read the laser energy. The overall system layout of the entire control and data acquisition system is shown in Fig. 3. It represents signal flow and connection diagram of the control and DAQ system. The signal from the PMT house is transfer to amplifier module (613A) through delay box for individual delay adjustment. The amplified output of the module is
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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Fig. 5. Calibration results for individual channels of the module.
Fig. 6. Scattered PMT signal acquired during the plasma discharge.
distributed to charge ADC (2249) and digital storage oscilloscope. The CAMAC controller and oscilloscopes are connected through GPIB cable in a daisy chain arrangement. For long distance transmission of the GPIB signal, GPIB to optical converters are used at both ends of the fiber cables.
4. Software program The software of TS diagnostic system has been built on LabVIEW platform. LabVIEW is graphical programming environment which helps engineers/scientists quickly to develop powerful and userfriendly software. A LabVIEW program consists of a numbers of
Virtual Instrument (VI) that consist of front panel and block diagram. Fig. 4 shows the front panel diagram of the ADITYA TS Diagnostic system. To meet the diagnostic data acquisition, the software is divided into two parts. The first part is to configure the diagnostic parameter for the Thomson Scattering and the second is for the measurement related parameters. The program automatically updates the shot number from the ADITYA server using TCP/IP protocol. The entire system becomes ready when the ADITYA Tokamak becomes ready for the next Plasma Discharge. The TS system resets every module and gets ready for the next shot after the main server updates the new shot number. The soft key button “Ready for New
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021
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5
Fig. 7. Typical temperature measurement for a plasma shot @ 40 ms.
shot” becomes green indicating the user about the event. The second part is to evaluate the experimental results, which include data acquisition, storage and processing. In the acquisition mode, laser is fired at a predefined time interval. The integration time window with predefined width (50–100 ns) is open upon the fast photo diode signal placed adjacent to the laser. The fast photo diode signal is also used as a trigger source for the digitizer module. The NI DAQ pad module records the energy of laser pulse at the same instance. All the acquired data through the charge integrator and the PMT signal traces from the DSO are displayed on the GUI and stored in a computer.
5. Results The developed DAQ system for TS is operational on ADITYA Tokamak. The acquisition time has been reduced significantly (earlier acquisition has transfer rate of around 1.2 KBps, which is very slow in comparison to present 1 MBps). The present GUI developed permits the user to configure the individual parameter of the system for a particular shot. The acquired data are linked to this configuration data, so that the correct information is documented and is available for processing the data. The calibration of the charge integrator module is performed with standard CAMAC charge generator module (Philips 7120). The scattered signal from the spectrometer for different wavelengths is acquired using PMT. Each PMT signal is digitized using CDC module. The CDC module integrates the PMT signal for the duration of the GATE interval and generates digital count corresponding to the area. The calibration result of the individual channels of the module is shown in Fig. 4. The developed instrument program reads digital count from module along with the PMT signal trace on the scope for the reference signal measurement. Fig. 6 shows the scattered PMT signal acquired form the oscilloscope during the plasma discharge. Each PMT signal defines a particular wavelength and signal integration of each channel gives the scattered photons for a particular wavelength. The signal from each channel is used for the calculation of the electron temperature and density. The program generates intensity vs wavelength graph and provides the required slope for the estimate of the temperature (Fig. 5).
Fig. 7 shows electron temperature plot for the plasma discharge @ 40 msec time intervals. The vertical axis is the log scale of the scattered intensity and the horizontal axis the delta lambda square. The temperature calculation is carried out using the method described in reference [14]. 6. Conclusion In this paper, an advanced automatic system based on a CAMAC and LabVIEW programming environment for ATS has been developed. It achieves synchronous control of equipment, real time data acquisition and data display. The upgraded DAQ and control system are improved for the performance of the diagnostics i.e. 1 MBps transmission speed in comparison of the earlier system. The developed system reduces the human error during the operation involving different instruments controlled independently. It also improves the data acquisition and processing capability and accuracy of the experiment. The developed control and data acquisition system has been integrated to ADITYA and successfully operated. Acknowledgments We gratefully acknowledge Dr. H.C. Joshi for fruitful discussion and critically evaluation of the manuscript. References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]
D. Johnson, et al., Rev. Sci. Instrum. 56 (1985) 1015. T.N. Carlstrom, et al., Rev. Sci. Instrum. 63 (10) (1992). K.R. Middaugh et al., General Atomics Report, GA-A23147 (1999). C.M. Greenfield, et al., Rev. Sci. Instrum. 61 (10) (1990). Y.G. Kim, et al., Fusion Eng. Des. 96–97 (2015) 882–886. Francesco Flora, et al., Appl. Opt. 26 (September (18)) (1987). K. Zhai, et al., Rev. Sci. Instrum. 75 (10) (2004). 3988 User Manual Kinetic System Corporation. 2323 User Manual LeCroy Corporation. 7120 User Manual Philips Corporation. 2249 User Manual LeCroy Corporation. C31034 series Photomultipliers Manual, RCA. LabVIEW User Manual, National Instrument Corporation. R. Rajesh, et al., Pramana 55 (2000) 733.
Please cite this article in press as: K. Patel, et al., GPIB based instrumentation and control system for ADITYA Thomson Scattering Diagnostic, Fusion Eng. Des. (2016), http://dx.doi.org/10.1016/j.fusengdes.2016.06.021