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Transcription

1 MA511

2 General Index 1 INTRODUCTION HARDWARE FEATURES: INTERFACE KEYBOARD POWER ON POWER OFF DETECTOR CONNECTION DETECTOR SUBSTITUTION DISPLAY LCD GENERAL PANEL DEVICE INFO PANEL MEASURE INFO PANEL SUPPLY INFO PANEL SPECTRUM PANEL ADDITIONAL PANEL MENU U MEASURE START STOP SAVE LOW CONSUMPTION BATTERY MANAGEMENT PC CONNECTION DETECTOR AND ISOTOPE CONFIGURATION... 17

3 1 Introduction The MA511 board is a radiation spectrum analyzer able to manage alone up to 7 different kind of phototube detectors, with the possibility to generate an internal HV between 300 V and 1000 V. The incoming analog input pass throws a Stretcher front-end, a mini-board able to sample and hold the signal and to generate a trigger signal towards the mother-board. A 10 bit ADC will acquire the input signal with a maximum rate of about 50 KHz which can be stored with efficiency equalization (user configured, detector dependent). Powered by internal Li-Ion batteries (rechargeable by USB supply connector), and provided of a wide alphanumeric LCD panel with a keyboard, the instrument can be used to measure and store in its internal memory RAM up to 20 energetic spectrum and several hours of counts rate, then downloadable to PC by an RS232/RS485 or a USB serial port. Two different alarm level can be set for a local acoustic warning (internal speaker or headphones) and for a remote warning by a relay activation. Moreover, energetic windows can be set to filter a specific radiation type, for isotope searching. Figure 1Block diagram of the MA511 board

4 1.1 Hardware features: Internal Li-Ion Battery USB Connector for battery recharge Phototube detector connector with: a. Power supply b. Analog input ADC 10 bit c. Detector type setting (up to 7 different type) Generation of internal HV (300 V 1000 V) 4 lines display LCD (alphanumeric) Keyboard (16 functional keys) Audio generation for warning and alarm to: Internal speaker External headphones 1 Relay activation for remote alarm 2 led for diagnostic 1 serial port RS232 / RS485 1 serial port USB

5 2 Interface Figure 2 MA511 interface Figure 2 shows the MA511 with all its part enhanced: LCD: 4 lines X 20 character alphanumeric display Keyboard: 16 functional keys (see 2.1) Detector connector: DB9 connector with supply, signal input and type identification HV connector: MHV connector for detector high voltage RS232 / RS485: DB9 connector for PC serial port interface USB: Usb connector for PC interface and battery recharge Relay: relay output for remote alarm activation Headphones: external output audio connector Charge Led: Red=battery charging; Green=battery charged; Off=battery charger off

6 2.1 Keyboard Figure 3 MA511 Keyboard The MA511 keyboard is a 16 functional keys one: On: Switch On MA511 Standby: puts MA511 in stand-by (see 6) Light: Switch on/off the display light (if configured for manual mode) Start/Stop: starts / ends a measure Memo Spettro: starts the procedure to store the last acquired spectrum Pan 1: shows the measure info panel (see 3.3) for 5 seconds Pan 2: shows the device info panel (see 3.2) for 5 seconds Pan 3: shows the supply info panel (see 3.4) for 5 seconds Pan 4: shows the spectrum panel (see 3.5); type Canc to exit Enter: accepts the selected item (displayed on LCD) Canc: cancel the operation or back to previous panel Menu: enter in the configuration menu Arrows: change/edit the selected item (or value). When in General panel (see 3.1) use Up and Down Arrows to modify audio level

7 2.2 Power On First connect the Detector to the instrument and the HV cable if the internal HV generation is required. After that press the key On to switch the MA511 on; a welcome panel will appear for few seconds, then the initialization procedure will check the detector presence and switches on the internal HV generator (if foreseen from user configuration). If no detector is found at start up MA511 will automatically switch off after a warning message. 2.3 Power Off Enter in the menu by pressing the Menu key; go down with the Down arrow to select the Power Off item and press Enter; a warning message will appear, press Enter to switch off the MA511. NB: when powered off, the instrument will loose all saved measure and configurations which are not written on internal flash memory. Be sure you don t need this before switching off, otherwise save the configurations in flash, download data to a PC or put the MA511 in Standby. 2.4 Detector connection If the internal HV generation is required you must first plug the HV and then the Detector connector. If internal HV is not required be sure to properly set the configuration flag in the menu (see 4) The MA511 is able to manage up to 7 different kind of detectors; the identification is made by a properly configuration of the Detector connector pins. Each Detector type has a preconfigured table in the MA511 with information about its usage (HV value, gain level, trigger level, conversion factors ). These tables can be edited and saved on internal flash memory (refers to the software PC manual or ask to your supplier). After the connection of the detector, the MA511 will automatically select the correspondent table and use it for its settings; if the correspondent table is not present a warning message will appear on the display. 2.5 Detector substitution It is possible to substitute a detector in each moment (only be sure to finish the eventual measure in progress, otherwise it will be automatically stopped). To do this, first disconnect the Detector Cable, then the HV one. After that connect the new HV cable and then the new Detector one. See also 2.4 for more info.

8 3 Display LCD The MA511 display is a 4 lines X 20 characters. When in normal use the MA511 will show the General panel (see 3.1), but it is possible to show the additional info panel by pressing the correspondent key on the keyboard (see 2.1). Each info panel will be shown for 5 seconds after the button release; the only exception is made by the Spectrum panel (see 3.5) which will be shown until the Canc key is pressed. 3.1 General Panel This is the main panel, which shows info about the battery status, counts and measure on progress. There are two different situations: MA511 in idle state (no measure on progress) MA511 in measure At the middle of the screen are indicated the counts (filtered by the selected isotope window) with the measure unit. The battery symbol indicates the battery charge subdivided in 5 levels. If the battery is recharging, the symbol will blink from 0 level to the actual one, otherwise no blink will be performed (a whole black symbol means battery completely charged). When the battery reaches the first level and is not charging the whole symbol will blink indicating low battery. The Counts over the window symbol means that more counts are present over the selected wfilter window When a measure is on progress, the corresponding progressive number and elapsed time will be shown.

9 3.2 Device Info Panel This panel shows info about the machine: The RS232/485 indicates the current hardware configuration of the serial port: RS232 or RS485. The Unit num is the number of the machine in a RS485 net. The serial speed is the configured speed of the serial port. 3.3 Measure Info Panel This panel shows info about the current status and settings for the measure: The window is the selected energy range of the filter for the counts computing. The Sel isotope is the selected isotope corresponding to the window, with its description. The Sel Tau is the selected integration time of the counts (is a value between 1 and 32 seconds) The N Detector is the current detector in use. The N saved spectrum is the number of saved spectrum on internal RAM (max is 20). The planned measure time is the time after when a measure is automatically stopped. The equalization on appears if the equalization table is used. The remote alarm on appears if the remote alarm is used. The local alarm on appears if the local alarm is used. The beep on appears if the beep is used.

10 3.4 Supply Info Panel This panel shows the tension voltages of the machine expressed in Volts. 3.5 Spectrum Panel This panel shows the last acquired (or acquiring) spectrum in a schematic form by using 20 cells for the whole energy range, reported on the bottom of the display. The vertical maximum is established referring to the max value inside the filter window currently selected. If no data is present in the spectrum buffer a warning message will appear. Press the Canc key to come back to the General panel. It is also possible to visualize a zoomed spectrum by pressing the Pan 4 key again (repeated pressure of this key will toggle between zoom and full spectrum). The zoomed spectrum is computed by reducing the whole energy range into 50 cells, showing 20 cells per time. Use the Left and Right Arrows to horizontally scroll the spectrum.

11 3.6 Additional panel It can be that none of the previous panel is shown on the display because of some warning message or an interactive panel like the Save spectrum one: In this case one of the 20 position is suggested; this is a free one, except the case of all position busy. It is possible to change the position by pressing the Arrow keys, save the spectrum by pressing Enter or don t save by pressing Canc.

12 4 Menu The internal menu of the MA511 can be used to set several machine parameters (to set detector and isotope table see 7.1). Press the Menu key to enter in the menu. It is possible to scroll the items by using the Up and Down Arrows in order to select the desired item (the selected item is indicated by the presence of a > character). Use the Arrows also to edit values; if a blinking cursor appear on the display it means that the value can be edited by singular digits, so you can use the Left and Right Arrows to change the selected digit. Press Enter to confirm, Canc to cancel or to go back to previous menu level. The menu is structured as follows: The write flash command will write all the user configuration values in the internal flash memory, so that MA511 will use them also on the next restart. The Set status and Set measure item structures are reported separately for a clearest vision.

13 The Audio item allows to enable/disable sounds (beep and local alarm) and remote alarm activation by the relay. It is also possible to set the level thresholds (expressed in the current unit of measure) of the alarm level; the min beep and max beep thresholds indicates the limit of the range in which the beep frequency has to dynamical vary. The Video items allows to set the LCD light intensity and time of activation at each pressure. The Measure unit allows to select the unit of measure of displayed values (scale will change automatically). The Auto low consumpt allows to enable/disable and select the time for the Auto low consumption mode (see 6). The Load default will restore all status parameter values from the internal flash ones. The Load factory will restore all status parameter values from the factory ones.

14 The Active isotope item allows to choose one of the configured isotope (see 7.1). The Integration time item allows to select the time of integration for the calculated counts rate (1 to 32 seconds); when 1 second is chosen, the audio response of the beep signal will be faster than others, due to a count integration only on the last 100 msec. The Measure time item allows to select the time after when a measure is automatically stopped or to put it in Manual mode (see 5). The Detector equaliz item allows to enable/disable the equalization of the computed counts rate using the detector efficiency table (see 7.1). The Preamp + HV item allows to enable/disable the generation of the internal Preamplifier power supply for the detector; the HV will also be generated if foreseen for the plugged detector. The Memorization item allows to select what to store during measures (rate and/or spectrum, see 5.3). The Load default will restore all measure parameter values from the internal flash ones. The Load factory will restore all measure parameter values from the factory ones.

15 5 Measure The MA511 normally performs Counts acquisition and display, with acoustic beep and alarm if foreseen. In the meanwhile supply checks are performed each 20 seconds. If you want to save data in the internal RAM and perform spectrum acquisitions you need to start a measure (after have properly set the measure memorization flags, see 5.3). When in measure the supply checks are reduced to one each 10 minutes (or on explicit request by user if the current value are older than 2 minutes) in order to improve the accuracy of the measurement. 5.1 Start To start a measure press the Start/Stop key. The measure will automatically stop when the foreseen time of measure is elapsed. It is possible to see which is the planned time watching the Measure info panel (see 3.3) and to edit it by Menu -> Set Config -> Set Measure -> Measure Time. If this time is Manual the measure will only stop on explicit user decision. 5.2 Stop It is always possible to stop a measure by pressing the Start/Stop key if a measure was in progress. 5.3 Save The MA511 allows to save up to 20 spectrum and several hours of counts. To enable the memorization you have to properly set the Menu -> Set Config -> Set Measure -> Memorization flag before starting the measure. After that, if the counts memorization has been selected, each measure will be saved in internal RAM by storing info like start time, detector in use, isotope in use, and a series of counts (filtered by window) taken each integration time τ. It is possible to see which is the current integration time watching the Measure info panel (see 3.3) and to edit it by Menu -> Set Config -> Set Measure -> Integration Time. The MA511 is able to store up to about events (so time duration heavily depends on the integration time); when this buffer is quiet full a warning message will appear on the display, and if measure is not stopped, the oldest value will be deleted. If the spectrum memorization has been selected, a panel asking where to save the acquired spectrum will appear at the end of the measure (see 3.6). If a spectrum is already present in a position it will be overwritten if the user choose to write over there. Each spectrum is saved with a descriptor with info like start time, detector in use, in the internal RAM. It is also possible to manually save the last acquired spectrum by pressing the Memo Spettro key, and the saving procedure will start even if the spectrum memorization has not been selected.

16 6 Low Consumption The MA511 allows two different type of low consumption mode: Stand-by Auto low consumption The Stand-by allows to retain the stored measure on internal RAM for a successive download to the PC; All functions are disabled (HV, Audio, Display, ) and the CPU is slowed in order to reach about a week of autonomy. It is possible to enter in Stand-by from the General panel (see 3.1) by pressing the Standby key. When in Stand-by, press the On key to come back to normal operation (in this case the welcome message will not be displayed). The Auto low consumption is a feature which can be enabled or disabled by user; it consists in an automatic switch off of the main function (HV, Audio, ) but leaving enabled the display and the CPU to normal speed, in order to reduce the consumption when the machine is not used for a specified time. When this feature is enabled the MA511 will pass in Auto low consumption if: 1. there is no measure on progress 2. there is no Usb cable connected 3. no keys are pressed for a time greater than the specified (10 min, 20 min, 30 min) To enable the feature and select the time set the Menu -> Set Config -> Set Status -> Auto low consumpt. 6.1 Battery management The batteries are automatically recharged each time a power supply is provided. The battery status is always indicated by a symbol in the General panel (see 3.1) and the tension value is written in the Supply info panel (see 3.4). Each time the battery voltage is checked (see 5), if the value is under 3.45 V the machine will automatically shift to Stand-by. If the value is under 3.0 V the machine will automatically switch off. It is important to recharge the battery before the switch off happens to not loose all saved measures.

17 7 PC connection The MA511 can be connected to the PC to download the saved measures, performs live acquisitions and set the machine configurations. There are two different way to connect the MA511 to a PC: 1. by Usb 2. by RS232/RS485 Usb: The connection by Usb can be made by: Install the Usb driver provided with the software to the PC Plug the Usb cable Link the PC and MA511 with the dedicated software at the speed of bps. RS232/RS485: The connection by RS232/RS485 can be made by: Check if the serial port is hardware configured in the correct way (RS232 or RS485); this info is showed in the Device info panel (see 3.2). If not contact your supplier to know hot to change it. Plug the serial cable Link the PC and MA511 with the dedicated software at the speed indicated in the Device info panel (see 3.2), using the unit number of the machine. It is possible to change speed and unit number only by using the Usb connection. 7.1 Detector and Isotope configuration The MA511 can manage up to 7 different detectors and 32 isotopes. Each detector type has to be configured in order to write an internal table with info about HV need, gain and trigger level, conversion factors, which are detector dependent parameters. Each isotope contain info about the filter window to use in the counts rate calculation, with a label indicating the name of the isotope. The configuration of detectors and isotopes can be only set with the dedicated software. Refer to the software manual for more info. When configured, MA511 automatically choose the right detector table at the detector plug in, while the isotope can be choose by user from Menu -> Set Config -> Set Measure -> Active isotope.