User manual VAISALA PTB220

[. . . ] PTB220 Series Digital Barometers USER'S GUIDE M210194EN-A AUGUST 2001 _________________________________________________________________________CONTENTS Table of contents CHAPTER 1 GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 PRODUCT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 BAROCAP® pressure sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Measurement principle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 CHAPTER 3 CHAPTER 4 GETTING STARTED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 COMMISSIONING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Operating modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 SMODE Selecting the sending mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 MMODE Selecting the measurement mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 PULSE Selecting the PULSE output mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Software settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 SERI Serial bus settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 ECHO Setting the serial bus echo on/off. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 FORM Defining the output format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 EFORM Defining the error output format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 DFORM Defining the display format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 UNIT Setting the pressure and temperature units. . . . . . . . . . . . . . . . . . . . 25 HHCP Setting the height of height correction. . . . . . . . . . . . . . . . . . . . . . . . . . . 25 AVRG Setting the averaging time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 INTV Setting the output interval. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 ADDR Setting the barometer address (for POLL mode) . . . . . . . . . . 27 SCOM User specific SEND command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 PSTAB Setting the pressure stability indicator . . . . . . . . . . . . . . . . . . . . . . . . . 29 PLARM Setting the pressure alarm levels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 PDMAX Setting the pressure difference limit . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 KEYLOCK Setting the keyboard lock on/off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Hardware settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Electrical connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Grounding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Pressure connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 OPERATING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 RUN and STOP modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 R Starting the continuous output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 S Stopping the output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 SEND Outputting a single message only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 V Verification message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 DNOS Self-diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 CHAPTER 2 CHAPTER 5 CHAPTER 6 VAISALA ___________________________________________________________________________I USER'S GUIDE_______________________________________________________________________ TRACK Setting the pressure tracking mode on/off. . . . . . . . . . . . . . . . . . 46 PLIM Pressure limit listing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 RESET Resetting the barometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 POLL mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] The housing of the barometer forms a static shield ground for the barometer. For the RS 232C serial interface, a separate ground is provided on pin 5 of the barometer, whereas for TTL level serial communication the pin 7 is recommended. Use pin 7 as ground also for the pulse output in the pulse output mode. As the shell of the Dconnector is in the same potential with the housing of the barometer, the user can ground the housing by means of the connector shell of the mating connector and the cable braid. In this case, the other end of the cable braid must also be appropriately grounded. In addition, the EMC stability of the barometer is further improved by grounding the barometer housing directly on an electrically conductive mounting surface with a serrated lock washer which breaks the painting of the housing. 40 ___________________________________________________________________ M210194EN-A CHAPTER 5_______________________________________________________________INSTALLATION The PTB220 series digital barometers comply with the CE norms for electromagnetic compatibility provided that braided cable and proper grounding techniques are used. The use of an unbraided cable may result in digital communication problems and erraneous measurements. Pressure connections The barometer is equipped with a barbed pressure fitting which is ideal for 1/8" internal diameter tubing. If some other pressure fitting need to be used, it is possible to replace the standard barbed fitting. The main pressure connector in the barometer housing has a metric M5 internal thread. It is, however, in practice possible to use pressure fittings with a non-metric 10-32 external thread together with this main pressure connector. Note that the barbed pressure fitting cannot be used in turbulent or high-speed static wind conditions. The barometric pressure measurement accuracy quoted for the PTB220 series digital barometers does not include any wind or air conditioning system induced measurement errors. The pressure fitting must also be protected from rain as water may get into the pressure connector and cause errors in the pressure measurement. The PTB220 barometers are designed to measure the pressure of clean, non-condensing, non-conducting and non-corrosive gases only. VAISALA _________________________________________________________________________ 41 CHAPTER 6________________________________________________________________ OPERATING CHAPTER 6 OPERATING Only a few commands are needed to operate a PTB220 barometer in the RUN, STOP and POLL modes. The user may also use his own SEND command if he has previously specified one using the SCOM command (see Chapter Software settings). In the POLL mode, the barometer responds to a SEND command only if it includes the address of the barometer. OPEN and CLOSE commands are also available for temporary communication with one single barometer. The barometer will automatically output one message at power-up, or when triggering the barometer on using pin 4 of the barometer. In the PULSE mode, the barometer requires a trigger pulse from the host system. In this case, the barometer must be powered-up separately and the pulse trigger signal must be given to the barometer after the settling time has elapsed. RUN and STOP modes are used in the RUN and STOP modes. In addition, the user may use his own SEND command if he has previously specified one with the SCOM commissioning command. The commands are not case sensitive except for the SCOM command. TABLE 6-1summarizes the commands that VAISALA _________________________________________________________________________ 43 USER'S GUIDE_______________________________________________________________________ TABLE 6-1 Commands used in RUN and STOP modes Command R S SEND V DNOS TRACK PLIM RESET Function starting output stopping output single message output verification message self-diagnostics pressure minimum/maximum tracking pressure limit listing resetting the barometer R Starting the continuous output R <cr> This command is used to start continuous outputting in the STOP and RUN modes and in interval output mode (see page 27). [. . . ] Section C, Code Table 0200: a - Characteristic of pressure tendency during the 3 hours preceding the time of observation describes the pressure tendency as follows: Code figure 0 Increasing, then decreasing; atmospheric pressure the same or higher than three hours ago Increasing, then steady; or increasing, then increasing more slowly; atmospheric pressure now higher than three hours ago Increasing (steadily or unsteadily); atmospheric pressure now higher than three hours ago Decreasing or steady, then increasing; or increasing then increasing more rapidly; atmospheric pressure now higher than three hours ago Steady; atmospheric pressure the same as three hours ago Decreasing, then increasing; atmospheric pressure the same or lower than three hours ago Decreasing, then steady; or decreasing, then decreasing more slowly; atmospheric pressure now lower than three hours ago Decreasing (steadily or unsteadily); atmospheric pressure now lower than three hours ago Steady or increasing, then decreasing; or decreasing then decreasing more rapidly; atmospheric pressure now lower than three hours ago 1 2 3 4 5 6 7 8 In addition to this the PTB220 series barometers output code * when the pressure tendency has not yet been calculated i. e. The absence of the pressure trend is indicated in the similar manner, too. VAISALA ________________________________________________________________________ 101 USER'S GUIDE_______________________________________________________________________ APPENDIX K ERROR MESSAGES The error/alarm messages of the PTB220 series digital barometers are: ERR / PASS (see DNOS command) HI ALARM (see PLARM command) LO ALARM (see PLARM command). The HI ALARM or LO ALARM are output by the barometer immediately and only once when the defined limit is exceeded, yet normal outputting is otherwise continued. A pressure out of range error occurs when the measured pressure exceeds the nominal pressure range of the barometer by 10 hPa. [. . . ]