PTB220 Series Digital Barometers USER'S GUIDE M210194EN-A AUGUST 2001
_________________________________________________________________________CONTENTS Table of contents CHAPTER 1 GENERAL INFORMATION.............................................................1 Safety ..............................................................................................1 Warranty .........................................................................................2 CHAPTER 2 PRODUCT DESCRIPTION .............................................................3 Introduction .......
USER'S GUIDE_______________________________________________________________________ TRACK Setting the pressure tracking mode on/off.................. 46 PLIM Pressure limit listing........................................................ 46 RESET Resetting the barometer ............................................. 47 POLL mode .................................................................................. 48 SEND Outputting one single message ....................................
_________________________________________________________________________CONTENTS APPENDIX F MULTIPLE PTB220 BAROMETERS ON RS232C.......................91 APPENDIX G OPTIONAL RS485/422 INTERFACE OF PTB220 BAROMETERS93 APPENDIX H SERIAL INTERFACE COMMANDS .............................................97 Commissioning commands........................................................97 Operating commands..................................................................97 Maintenance commands ................
CHAPTER 1_______________________________________________________ GENERAL INFORMATION CHAPTER 1 GENERAL INFORMATION Safety Throughout the manual important instructions regarding the safety considerations are focused as follows. WARNING Warning denotes a hazard. It calls attention to a procedure, practice, condition or the like, which, if not correctly performed or adhered to, could result in injury to or death of personnel. CAUTION Caution denotes a hazard.
USER'S GUIDE_______________________________________________________________________ Warranty Vaisala hereby represents and warrants all Products manufactured by Vaisala and sold hereunder to be free from defects in workmanship or material during a period of twelve (12) months from the date of delivery save for products for which a special warranty is given.
CHAPTER 2___________________________________________________ PRODUCT DESCRIPTION CHAPTER 2 PRODUCT DESCRIPTION Introduction The PTB220 series barometers are fully compensated digital barometers designed to cover a wide range of environmental pressure and temperature. They can be used successfully both in accurate pressure measurement applications at room temperature and in demanding automatic weather station applications.
USER'S GUIDE_______________________________________________________________________ The PTB220 series digital barometers are available with one, two or three pressure transducers. Although one pressure transducer is usually the most appropriate configuration, some applications may benefit from additional pressure transducers. Two or three pressure transducers provide for a self-diagnostic feature: the user can set an alarm limit within which the pressure transducers must agree for reliable measurement.
CHAPTER 2___________________________________________________ PRODUCT DESCRIPTION Silicon diaphragm Thin film metallization Silicon Glass Silicon Vacuum gap FIGURE 2-1 The BAROCAP® pressure sensor The BAROCAP® pressure sensor consists of two layers of single crystal silicon having a layer of glass between them. The thinner silicon layer is etched on both sides to create an integrated vacuum reference chamber for the absolute pressure sensor and to form a pressure sensitive silicon diaphragm.
USER'S GUIDE_______________________________________________________________________ Measurement principle The measurement principle of the PTB220 series digital barometers is based on an advanced RC oscillator with three reference capacitors against which the capacitive pressure sensor and the capacitive temperature compensation sensor are continuously measured.
CHAPTER 2___________________________________________________ PRODUCT DESCRIPTION Block diagram The PTB220 series digital barometers consist of a CPU board and 1, 2 or 3 pressure transducers (P1, P2 and P3). The number of pressure transducers is order specific and the configuration cannot be changed by the user. Usually the pressure transducers are connected to the same pressure port. However, in case of two pressure transducers, the barometer can have also two pressure ports, one for each transducer.
CHAPTER 3___________________________________________________________ GETTING STARTED CHAPTER 3 GETTING STARTED As the PTB220 series digital barometers always have an RS 232C serial interface, the user is requested to use this interface when operating the barometer for the first time. The RS 232C is the most useful and reliable interface for commissioning the barometers with various software settings.
USER'S GUIDE_______________________________________________________________________ The factory settings of the PTB220 series barometers are the following: TABLE 3-1 Serial interface factory settings Baud rate Parity Data bits Stop bits Duplex 9600 even 7 1 full duplex After having made the electrical connections, switch the power on, and the barometer responds indicating the barometer type and the software version. PTB220 / 2.
CHAPTER 4_____________________________________________________________ COMMISSIONING CHAPTER 4 COMMISSIONING TABLE 4-1summarizes the commands used to commission the PTB220 series digital barometers. The commands are not case sensitive except for the SCOM command.
USER'S GUIDE_______________________________________________________________________ Operating modes The first thing to do is to select the desired sending mode for the barometer. This is done with the command SMODE. There are available the normal or the fast measurement mode or the pulse output mode. These selections are made with MMODE and PULSE commands.
CHAPTER 4_____________________________________________________________ COMMISSIONING NOTE Remember to give the RESET command to initialize the new sending mode. MMODE Selecting the measurement mode MMODE x where: x = NORMAL or FAST The MMODE command is used to set or inspect the measurement mode of the barometer. In the normal measurement mode, the barometer measures the capacitance of each of the five capacitive components of the pressure transducer (see page 6).
USER'S GUIDE_______________________________________________________________________ Mtim : >filt off Filter : OFF >reset NOTE 32 Remember to give the RESET command to initialize the new measurement mode. The measurement time (mtim) setting of 32 is recommended in order to achieve the best output stability at the speed of 10 measurements per second. The filter command ensures that no numerical filtering is performed in the fast measurement mode.
CHAPTER 4_____________________________________________________________ COMMISSIONING NOTE The pulse output mode can be used with hPa/mbar pressure units only! Example of software settings for the pulse output mode: >pulse OFF SLOW LOW 0.0 >pulse on slow low ON SLOW LOW 0.0 >pulse on fast high -800 ON FAST HIGH -800.0 >pulse off OFF FAST HIGH -800.
USER'S GUIDE_______________________________________________________________________ Software settings SERI Serial bus settings SERI b p d s x where: b p d s x (* = factory setting) = = = = = = baud rate (300, 600, 1200, 2400, 4800, 9600*) parity (E = even*, O = odd, N = none) data bits (7* or 8) stop bits (1* or 2) duplex (F = full* or H = half) carriage return is generated by the ENTER or RETURN key of the host computer The SERI command is used to set or inspect the serial bus settings of the
CHAPTER 4_____________________________________________________________ COMMISSIONING The RS485/422 interface of the PTB220 series digital barometers is a non-isolated two-wire half-duplex interface. See page 93 for quick reference information on how to use the RS485/422 interface of the PTB220 series digital barometers. ECHO Setting the serial bus echo on/off ECHO x where: x = ON or OFF The ECHO command is used to set or inspect the echoing condition of the barometer.
USER'S GUIDE_______________________________________________________________________ pressure quantities height corrected pressure pressure trend *) pressure tendency temperature quantities *) pressure and temperature units address of the barometer error status stability indicator checksums number fields text fields ASCII characters: CR LF TAB nnn ASCII code P1 (reading of the transducer 1), P2 (transducer 2), P3 (transducer 3), P (average) HCP (see also page 25) TREND (three-hour trend) A (see page 101 fo
CHAPTER 4_____________________________________________________________ COMMISSIONING Examples of different ways of setting the output format: 1. To output the pressure reading. >form 4.2 P " " UUUU #r #n ? >send 1020.30 hPa > 2. To output the transducer values (P1,P2,P3) separately and the average value (P). >form 4.2 P " " UUUU #r #n ? 4.2 P1 " " P2 " " P3 " " P " " UUU #r #n >send 1020.31 1020.32 1020.33 1020.32 hPa > 3.
USER'S GUIDE_______________________________________________________________________ 6. To output the average pressure reading in the units of inHg . >form 4.2 P " " UUU #r #n ? 2.4 P " " UUUU #r #n >unit inHg P unit : inHg >send 30.1234 inHg > 7. Adding a text field, giving the address and outputting the pressure reading from a identified barometer. >form 4.2 P " " UUUU #r #n ? "Barometer " ADDR " " 4.2 P " " UUU #r #n >addr 7 Address : 7 >send 7 Barometer 07 1020.
CHAPTER 4_____________________________________________________________ COMMISSIONING >form 4.2 P " " UUUU #r #n ? 4.2 P1 " " P2 " " P3 " " P " " UUU " " ERR #r #n >send 1020.30 1020.31 1020.32 1020.31 hPa 000 >send 1020.30 1022.31 1020.32 1020.31 hPa 010 (Pd max error) > >form 4.2 P " " UUUU #r #n ? 4.2 P1 " " P2 " " P3 " " P " " UUU " " ERR #r #n >send 1020.30 1020.31 1020.32 1020.31 hPa 000 >send 1020.30 1022.31 1024.32 1022.31 hPa 111 (Pd max error) > 10.
USER'S GUIDE_______________________________________________________________________ EFORM Defining the error output format EFORM The EFORM command is used to define the user specific error output format for the serial interface. In case of an internal error, the barometer outputs the message defined with the EFORM command instead of the normal message defined with the FORM command.
CHAPTER 4_____________________________________________________________ COMMISSIONING *) The PTB220 barometer cannot output + sign for pressure trend or temperature reading; a space is output instead. There are two rows containing 16 characters each; the user can define a maximum of 32 characters to be displayed. The field definitions are defined in successive order so that the first 16 characters will be displayed on the first row and the next characters on the second row.
USER'S GUIDE_______________________________________________________________________ The PTB220 series barometers will show * instead of numeric values for pressure trend and pressure tendency for three hours from powerup. In case of error in the barometer, the relevant error message will automatically appear on the second line of the display. In this case, any other information defined using the DFORM command will be replaced with an error message.
CHAPTER 4_____________________________________________________________ COMMISSIONING UNIT Setting the pressure and temperature units UNIT x where (* = factory setting) x = hPa* kPa Pa mbar inHg mmHg torr mmH2O psia C* F This command is used to set and inspect the pressure and internal temperature compensation unit. The temperature unit is not confirmed by the barometer. Example of changing the pressure and temperature units: >unit P unit : hPa >unit C >send 1035.19 hPa 25.
USER'S GUIDE_______________________________________________________________________ where: P= 0.1176 = h= measured pressure constant height Example of setting the height: >hhcp Height of HCP : ? -30 > AVRG Setting the averaging time AVRG x where: x = 1 ... 600 (seconds) The AVRG command is used to set and inspect the averaging time during which the individual measurement samples are integrated to get an averaged pressure reading. The averaging time is the total averaging time of the barometer.
CHAPTER 4_____________________________________________________________ COMMISSIONING INTV Setting the output interval INTV x y where: x = output interval (0...255) y = unit (s, min, h) This command is used to set and inspect the interval output mode. The R command is used to start the outputting. Examples: NOTE >intv Output intrv. : > 0 s >intv 10 s Output intrv.
USER'S GUIDE_______________________________________________________________________ >addr 7 Address > : 7 A new address replaces the previous one. Always set the address to 0 when no address is needed: >addr 0 Address > : 0 If the barometer is not closed in the POLL mode, it will respond to any SEND command (regardless of the address). The barometer must be set to POLL mode and then closed with CLOSE command (see Chapter POLL mode).
CHAPTER 4_____________________________________________________________ COMMISSIONING Example of defining a similar command without an end character: >scom "P" #r ? "P" >P1020.
USER'S GUIDE_______________________________________________________________________ fluctuations, and for example opening the door of a room will often result in temporary pressure instability. PLARM Setting the pressure alarm levels PLARM x y where: x = the low alarm level (LO ALARM) y = the high alarm level (HI ALARM) The PLARM command is used to set or inspect the low and high pressure alarm levels.
CHAPTER 4_____________________________________________________________ COMMISSIONING x = pressure reading (in current unit) This command is used to define the maximum pressure difference between the pressure readings from different pressure transducers (P1/P2 or P1/P2/P3). If the defined value is exceeded, the relevant digits in the ERR field (see FORM command) will change from 0 to 1.
USER'S GUIDE_______________________________________________________________________ > >form 4.2 P " " UUUU #r #n ? 4.2 P1 " " P2 " " P3 " " P " " UUU " " ERR #r #n >send 1020.30 1020.31 1020.32 1020.31 hPa 000 >send 1020.30 1022.31 1020.32 1020.31 hPa 010 >send 1020.30 1022.31 1024.32 1022.31 hPa 111 Note that only the acceptable pressure readings are used to calculate the average output pressure reading.
CHAPTER 4_____________________________________________________________ COMMISSIONING CL ENT Hardware settings Inside the barometer, there is the connector X15 (see FIGURE 4-2) and the dip switch S1 (see FIGURE 4-3). These are used to make the main hardware settings of the PTB220 series digital barometers. With the connector X15, the user can select the RS 232C (RX, TX) or TTL levels for serial communication.
USER'S GUIDE_______________________________________________________________________ An external power control can be used to switch the PTB220 barometer ON/OFF. The control is activated with the switch SW2 in position ON as shown in FIGURE 4-4. The TTL signals are: 0VDC OFF and 5VDC ON.
CHAPTER 4_____________________________________________________________ COMMISSIONING TABLE 4-2 Summarized settings of the dip switch S1.
CHAPTER 5_______________________________________________________________ INSTALLATION CHAPTER 5 INSTALLATION Mounting In automatic weather station applications and in other harsh operating environments, the PTB220 series digital barometers have to be installed inside a weather resistant or otherwise protective enclosure. The pressure fitting must also be protected from rain as water may get into the pressure connector and cause errors in the pressure measurement.
USER'S GUIDE_______________________________________________________________________ 145 133 120 ø6.
CHAPTER 5_______________________________________________________________ INSTALLATION TABLE 5-2 PIN 1 2 3 4 5 6 7 8 9 Pin assignment for RS 232C/485/422 SIGNAL TX with diode TX/TXD/TXD inverted RX/RXD/RXD inverted external power on/off control ground for the RS 232C RS 485/422 LO ground for supply voltage and TTL level serial interface RS 485/422 HI supply voltage (10...30 VDC) In barometers with RS232/analog output, the pin assignment is as follows.
USER'S GUIDE_______________________________________________________________________ The two-wire half duplex RS 485/422 serial interface is the recommended way of connecting the PTB220 series barometers with other intelligent transmitters (see FIGURE 5-4). See page 93 for quick reference information on how to use the RS485/422 interface of the PTB220 series barometers. HOST COMPUTER RX/TX HI LO HI RX/TX LO PTB220 HI RX/TX LO ........... HI RX/TX LO ...........
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.
CHAPTER 6________________________________________________________________ OPERATING CHAPTER 6 OPERATING Only a few commands are needed to operate a PTB220 barometer in the RUN, STOP and POLL modes. In the SEND mode and in the PULSE mode no commands are needed. In the RUN or STOP modes the commands R, S and SEND can be used. The user may also use his own SEND command if he has previously specified one using the SCOM command (see Chapter Software settings).
USER'S GUIDE_______________________________________________________________________ TABLE 6-1 Commands used in RUN and STOP modes Function starting output stopping output single message output verification message self-diagnostics pressure minimum/maximum tracking pressure limit listing resetting the barometer Command R S SEND V DNOS TRACK PLIM RESET R Starting the continuous output R This command is used to start continuous outputting in the STOP and RUN modes and in interval output mode (see pag
CHAPTER 6________________________________________________________________ OPERATING SEND Outputting a single message only SEND This command is used to output one message at a time in the STOP and RUN modes. Example: >reset PTB220 / 2.02 >send 1013.25 hPa > The user may also use his own previously specified one-message command (see Chapter SCOM command on page 12). V Verification message V The V command is used to output the verification message of the barometer.
USER'S GUIDE_______________________________________________________________________ >dnos ERR > TRACK Setting the pressure tracking mode on/off TRACK The TRACK command is used to activate or deactivate the minimum/ maximum pressure tracking mode of the barometer. When activated, the barometer stores in memory the minimum and maximum pressure values measured. At power-up the tracking mode is always deactivated.
CHAPTER 6________________________________________________________________ OPERATING Example: >track off Min/max track.: >plim Stab. level : Max : Min : Hi alarm : Lo alarm : >track on Min/max track.: >plim Stab. level : Max : Min : Hi alarm : Lo alarm : > OFF 0.50 hPa OFF OFF 1100.00 hPa 500.00 hPa ON 0.50 1020.31 987.65 1100.00 500.
USER'S GUIDE_______________________________________________________________________ POLL mode TABLE 6-2 summarizes the commands used in the POLL mode. The commands are not case sensitive. TABLE 6-2 Commands used in RUN and STOP modes Function single message output opening a barometer closing a barometer Command SEND a OPEN a CLOSE The POLL mode is used when several PTB220 series barometers are connected to one RS232C serial interface for fine adjustment and calibration in one batch.
CHAPTER 6________________________________________________________________ OPERATING OPEN Setting a barometer from POLL mode to STOP mode CLOSE Setting a barometer from STOP mode to POLL mode OPEN a CLOSE where: a = the address of the barometer (0 ... 99) These commands are used to set a barometer temporarily to STOP mode and back to POLL mode again.
USER'S GUIDE_______________________________________________________________________ Example of closing a barometer: >close line closed SEND mode In the SEND mode the barometer will automatically output one message at power-up or when triggering the barometer on using pin 4 of the barometer. The trigger signal must be a TTL level signal. TTL HIGH (5 VDC) turns the barometer ON and TTL LOW (0 VDC) turns the barometer OFF.
CHAPTER 6________________________________________________________________ OPERATING PULSE mode In the PULSE output 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. The trigger signal must be a TTL level signal. The pulse output is triggered at the falling edge of the TTL trigger signal from TTL HIGH (5 VDC) to TTL LOW (0 VDC).
USER'S GUIDE_______________________________________________________________________ 5. Use ENT key to acknowledge a selection. The selected characters then move one step to the left and the next character can be selected. Entering characters is ended by selecting a space ' ' and then by pressing ENT key. Note that modifications made using the keyboard will affect the serial interface settings, too.
CHAPTER 6________________________________________________________________ OPERATING FIGURE 6-1 Available functions and selections of the local display See Chapter Software settings for more information on: - averaging time setting (see AVRG command) - pressure stability indicator setting (see PSTAB command) - pressure difference limit setting (see PDMAX command) - pressure alarm setting (see PLARM command) VAISALA _________________________________________________________________________ 53
USER'S GUIDE_______________________________________________________________________ - serial interface setting (see SERI command) - pressure and temperature unit setting (see UNIT command). See Chapter 3.1 Operating modes for more information on: - measurement setting (see MMODE command). The MTIM setting is automatically selected to be 32 and filter setting FILT OFF when the MMODE FAST is selected using the keyboard. See Chapter 5.
CHAPTER 7__________________________________________________ ADJUSTMENT AND CALIBRATION CHAPTER 7 ADJUSTMENT AND CALIBRATION Introduction The PTB220 series digital barometers can be fine adjusted and calibrated against pressure standards that have high accuracy and stability as well as known traceability to international standards. For Class A barometers, standards with uncertainty of ±70 ppm (±2 standard deviation value) or better should be used.
USER'S GUIDE_______________________________________________________________________ given in the calibration certificate together with a description of the international pressure traceability chain. In calibration laboratory conditions, the pressure readjustment of a PTB220 series digital barometer is made by first deactivating the linear and multipoint corrections using both the LC OFF and MPC OFF commands.
CHAPTER 7__________________________________________________ ADJUSTMENT AND CALIBRATION TABLE 7-1 Adjustment and calibration commands (*only with the optional analog output) Function listing corrections linear corrections on/off multipoint corrections on/off entering linear corrections entering multipoint corrections calibration date entering linear corrections * Command CORR LC ON/OFF MPC ON/OFF LCI MPCI CALD DLCI * The linear and multipoint corrections are protected by switch SW4.
USER'S GUIDE_______________________________________________________________________ In case of one transducer, the listing looks as follows: >corr Linear adjustments Multipoint adjustments Reading Correction 499.720 -0.070 599.200 -0.080 698.710 -0.010 801.120 -0.010 900.610 -0.030 947.420 -0.020 1000.100 -0.040 1099.580 -0.040 Calibration date > OFF ON 1997-01-01 In case of two transducers, the listing looks as follows: >corr Linear adjustments Multipoint adjustments Reading Correction 499.
CHAPTER 7__________________________________________________ ADJUSTMENT AND CALIBRATION LC Linear corrections LC x where: x = ON or OFF The LC command is used to activate or deactivate the linear offset or offset/gain corrections. The linear corrections are protected with switch SW4 (see FIGURE 7-1). The switch SW4 is normally in write DISABLE position (OFF) and the user must change it to write ENABLE position (ON) to be able to turn the linear corrections on or off.
USER'S GUIDE_______________________________________________________________________ MPC Multipoint corrections MPC x where: x = ON or OFF The MPC command is used to activate or deactivate the multipoint corrections. The multipoint corrections are protected with switch SW4 (see FIGURE 7-1). The switch SW4 is normally in write DISABLE position (OFF) and the user must change it to write ENABLE position (ON) to be able to turn the multipoint corrections on or off.
CHAPTER 7__________________________________________________ ADJUSTMENT AND CALIBRATION Offset and gain adjustment LCI Entering linear corrections LCI n where: n = number of the pressure transducer (1, 2 or 3) The LCI command is used to enter new linear offset and offset/gain corrections to the barometer. Note that the user must give the linear corrections to each pressure transducer separately. Entering new linear corrections is protected by switch.
USER'S GUIDE_______________________________________________________________________ NOTE Always remember to return the switch SW4 to write DISABLE position (OFF). Multipoint adjustment MPCI Entering multipoint corrections MPCI n where: n = number of the pressure transducer (1, 2 or 3) The MPCI command is used to enter new multipoint corrections to the barometer. Note that the user must give the multipoint corrections to each pressure transducer separately.
CHAPTER 7__________________________________________________ ADJUSTMENT AND CALIBRATION correction ? -0.08 3. reading ? 698.71 correction ? -0.01 P1 4. reading ? 801.12 correction ? -0.01 P1 5. reading ? 900.61 correction ? -0.03 P1 6. reading ? 947.42 correction ? -0.02 P1 7. reading ? 1000.10 correction ? -0.04 P1 8. reading ? 1099.58 correction ? -0.04 >mpc on Multipoint adj: ON Reading Correction 499.720 -0.070 599.200 -0.080 698.
USER'S GUIDE_______________________________________________________________________ CALD Storing the new date of calibration CALD yyyy-mm-dd This command is used to store the new valid date of calibration in the memory of the barometer.
CHAPTER 8____________________________________________ SELF-TESTING AND PROBLEM HANDLING CHAPTER 8 SELF-TESTING AND PROBLEM HANDLING Returning the serial communication parameters As the barometer software and hardware settings may not always be known, it is important that the barometer can be returned to factory settings. To do this, set the dip switch S1 on the CPU board as in FIGURE 8-1. All switches except the SW8 must be OFF.
USER'S GUIDE_______________________________________________________________________ TABLE 8-1 Serial interface factory settings Baud rate Parity Data bits Stop bits Duplex 9600 even 7 1 full duplex Diagnostic commands The PTB220 series digital barometers respond to a set of diagnostic commands, which are useful for analyzing the basic settings and general operation of the barometers.
CHAPTER 8____________________________________________ SELF-TESTING AND PROBLEM HANDLING Output format Error output format SCOM format Pressure unit Temperature unit Averaging time > NOTE 4.2 P " " UUUU #r #n hPa 'C 1.0 s This command must be used only for one barometer at a time. Any PTB220 series barometer will always respond to ?-command whatever its settings are, provided that the serial interface settings are correct.
USER'S GUIDE_______________________________________________________________________ >errs E00 Nothing special to report > Complete list of error codes: E00 E10 E20 E11 E14 E21 E24 E31 E41 E51 E61 E71 E12 E22 E32 E42 E52 E62 E72 E13 E23 E33 E43 E53 E63 E73 Nothing special to report CPU EEPROM ackn. error CPU EEPROM csum error P1 EEPROM ackn. error DAC EEPROM ackn.
CHAPTER 8____________________________________________ SELF-TESTING AND PROBLEM HANDLING C n Listing transducer coefficients C n where n = number of the pressure transducer (1, 2 or 3) The C n command is used to list all internal coefficients of a transducer. These coefficients are for factory use only and they cannot be changed by the user.
USER'S GUIDE_______________________________________________________________________ The response to the PTEST command in the serial interface consists of the pressure reading, pressure reading corrected with defined offset and the number of pulses to be output. See the PULSE command in Chapter Operating modes for information on how to make the settings of pulse output mode. The switch SW3 may be in position ON or OFF (see Chapter Hardware settings) when the PTEST command is being used.
CHAPTER 9____________________________________________________ TECHNICAL SPECIFICATIONS CHAPTER 9 TECHNICAL SPECIFICATIONS Barometric pressure Operating range 50...1100 hPa, 500...1100 hPa Pressure ranges Temperature range operating with local display storage with local display Humidity range Accuracy -40 ... +60 ºC 0 ... +60 ºC -60 ... +60 ºC -20 ... +60 °C non-condensing Pressure range: 500...1100 hPa 0.1 % R1 class A 50...1100 hPa class B Linearity* ± 0.05 hPa ± 0.05 hPa ± 0.10 hPa ± 0.
USER'S GUIDE_______________________________________________________________________ *** Defined as the root sum of the squares (RSS) of end-point nonlinearity, hysteresis error, repeatability error and calibration uncertainty at room temperature. **** Defined as ±2 standard deviation limits of temperature dependence over the operating temperature range.
CHAPTER 9____________________________________________________ TECHNICAL SPECIFICATIONS Mechanics Pressure connector Pressure fitting Maximum pressure limit Minimum pressure limit Electrical connector Housing Weight M5 (10-32) internal thread barbed fitting for 1/8" I.D. tubing 5000 hPa abs. 0 hPa female 9-pin subD-connector epoxy painted aluminium 1 kg Dimensions in mm (inches): 25.6 (1.01) 65 (2.56) 120 (4.72) 145 (5.71) 133 (5.24) FIGURE 9-1 120 (4.72) 139.5 (5.49) 104 (4.09) 6.5 (0.
USER'S GUIDE_______________________________________________________________________ EN 61326-1:1997 +Am 1:1998, Electrical equipment for measurement, control and laboratory use - EMC requirements; Generic environment.
CHAPTER 9____________________________________________________ TECHNICAL SPECIFICATIONS 25328 Quick coupling 25329 Tube fitting The PTB220CASE kit includes an oak case, a sealed lead acid battery and recharging electronics (order code: PTB220CASE).
APPENDIX A __________________________________________________ HARDWARE CONFIGURATIONS APPENDIX A HARDWARE CONFIGURATIONS FIGURE A-1 FIGURE A-2 Configuration with one pressure transducer Configuration with two pressure transducers VAISALA _________________________________________________________________________ 77
USER'S GUIDE_______________________________________________________________________ FIGURE A-3 Configuration with three pressure transducers FIGURE A-4 Configuration with two pressure transducers and two pressure ports 78 ___________________________________________________________________ M210194EN-A
APPENDIX B ___________________________________________________________PIN ASSIGNMENTS APPENDIX B PIN ASSIGNMENTS The pin assignment of the 9-pin female subD-connector of the PTB220 series digital barometers seen from the front: 5 43 21 9 8 76 In barometers with RS232C/TTL level serial/pulse output interface, the pin assignment is as follows: PIN 1 2 3 4 5 6 7 SIGNAL TX with diode TX/TXD/TXD inverted RX/RXD/RXD inverted external power on/off control ground for the RS 232C pulse output (TTL level) ground
USER'S GUIDE_______________________________________________________________________ In barometers with RS232/analog output, the pin assignment is as follows. PIN 1 2 3 4 5 6 7 8 9 SIGNAL TX with diode TX/TXD/TXD inverted RX/RXD/RXD inverted external power on/off control ground for the RS 232C voltage output (0...5 VDC) / current output (0...20 mA) ground for supply voltage voltage output ground / current input ground supply voltage (10...
APPENDIX C __________________________________________ RS232C/TTL LEVEL SERIAL INTERFACE APPENDIX C RS232C/TTL LEVEL SERIAL INTERFACE The Appendix C shows connection of handshaking lines and the wave forms, voltage levels and phases of the RS232C/TTL level serial interface signals. Handshaking lines (DCD, CTR, DSR, RTS and CTS) may have to be connected at the host system end as illustrated below: 9-pin D connector 25-pin D connecto 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 ... 20 ...
USER'S GUIDE_______________________________________________________________________ The next picture (below) shows a typical RS232C TX output signal (upper signal) and TTL level serial TXD output signal (lower signal) at baud rate 9600. The vertical scale is 5V/div for upper signal and 2V/div for lower signal. The ground level is shown with a small arrow at the right. At the left, the signals are at rest.
APPENDIX D ____________________________________________________ PULSE OUTPUT MODE APPENDIX D PULSE OUTPUT MODE NOTE The pulse output mode can be used with hPa/mbar pressure units only. The pulse output mode of the PTB220 series barometers is useful when no serial interface is available in the host system. A standard pulse counter interface is all that is needed to count the number of pulses output by the barometer.
USER'S GUIDE_______________________________________________________________________ The figure below illustrates in practice the falling edge of the trigger pulse (lower signal) and the start of pulse outputting (upper signal). The gate-open time may be calculated in practice using a simple formula: maximum number of output pulses pulse rate (Hz) + 0.5 ... 1 second (D-1) If SLOW pulse rate (appr. 5 kHz) and LOW resolution (0.
APPENDIX D ____________________________________________________ PULSE OUTPUT MODE at 1100 hPa/mbar pressure. The gate-open time could be 0.5 ... 1 second. The pulse output mode settings must be made on two levels: - software settings - hardware settings. Example of software settings for the pulse output mode: >pulse OFF SLOW LOW 0.0 >pulse on slow low ON SLOW LOW 0.0 >pulse on fast high -800 ON FAST HIGH >pulse off OFF FAST HIGH > (note the negative sign of pressure offset) -800.
USER'S GUIDE_______________________________________________________________________ >pulse ON SLOW LOW 0.0 >ptest 1000 (outputting pre-defined pressure 1000.0 hPa) 1000.000 1000.000 10000 >pulse slow low -800 ON SLOW LOW -800.0 >ptest 1000 1000.000 200.000 2000 > NOTE In case of an error in a PTB220 series barometer, there will be no pulse output from the barometer despite an external trigger pulse.
APPENDIX E ___________________________________________________________ ANALOG OUTPUT APPENDIX E ANALOG OUTPUT The optional analog output module has two selectable operating modes: current (4...20mA) and voltage (0...5V). There are four additional serial commands in use for operating the barometer having the analog output module.
USER'S GUIDE_______________________________________________________________________ Examples of setting the pressure limits: >ascl P Low : 500 ? P High : 1100 ? > 800 1100 (0V/4mA = 800 hPa) (5V/20mA = 1100 hPa) ITEST x.xx where: x = current or voltage value to be checked The operation of the analog output can be tested by forcing the output to given values, which can be measured with a current/voltage meter from the analog output.
APPENDIX E ___________________________________________________________ ANALOG OUTPUT 1. Open the cover of the barometer and set the dip switch SW4 to upward position (ON). 2. Use the serial line to give the command LC OFF, which deactivate the linear correction. 3. Give the command ITEST X1 and measure the output current / voltage. X1 is a value close to the lower end of full range, for example, 0.5 in voltage or 5 in current output mode. 4. Give the command ITEST X2 and measure the output current/voltage.
USER'S GUIDE_______________________________________________________________________ 9. Remember to restore the dip switch SW4 (OFF). NOTE Entering new linear corrections will always cancel the previous corrections. It is advisable to write down the factory set linear corrections so that they will not be lost by mistake.
APPENDIX F _________________________________ MULTIPLE PTB220 BAROMETERS ON RS232C APPENDIX F MULTIPLE PTB220 BAROMETERS ON RS232C It is possible to connect multiple PTB220 series digital barometers on one RS232C interface for example for fine adjustment and calibration of several barometers in one batch. The PTB220 series barometers have a special transmission terminal for this kind of use as pin 1 (TX with diode) has a built-in diode in series with the TX line.
APPENDIX G ______________________OPTIONAL RS485/422 INTERFACE OF PTB220 BAROMETERS APPENDIX G OPTIONAL RS485/422 INTERFACE OF PTB220 BAROMETERS The two-wire non-isolated half duplex RS 485/422 serial interface is the recommended way of connecting the PTB220 series barometers with other intelligent transmitters. HOST COMPUTER RX/TX HI LO HI RX/TX LO PTB220 HI RX/TX LO ........... HI RX/TX LO ...........
USER'S GUIDE_______________________________________________________________________ >addr 7 Address : >smode poll Serial mode : POLL >reset send 7 1013.25 hPa (select address of the barometer) 7 (select the POLL mode) (resetting will activate the new settings) (no title will appear after reset in POLL mode) (text invisible) The next picture (below) shows typical RS485/422 differential input signals RS485/422 LO (upper signal) and RS485/422 HI (lower signal) at baud rate 9600.
APPENDIX G ______________________OPTIONAL RS485/422 INTERFACE OF PTB220 BAROMETERS VAISALA _________________________________________________________________________ 95
APPENDIX H _______________________________________________ SERIAL INTERFACE COMMANDS APPENDIX H SERIAL INTERFACE COMMANDS Commissioning commands Function sending mode measurement mode pulse mode settings serial bus settings echo on / off output format pressure resolution pressure trend pressure tendency error status stability indicator checksum error output format display format pressure and temperature units averaging time setting output interval address of the barometer user specific SEND command pressur
USER'S GUIDE_______________________________________________________________________ Maintenance commands Function listing linear and multipoint corrections linear corrections on/off entering linear corrections multipoint corrections on/off entering multipoint corrections calibration date entering linear corrections of analog output * only with the optional analog output Command CORR LC ON/OFF LCI MPC ON/OFF MPCI CALD DLCI* Diagnostic commands Function basic information on settings software version serial
APPENDIX I ________________________________________________________________ CHECKSUM APPENDIX I CHECKSUM With a CHECKSUM form the user can check that the data sent by the barometer has not changed in transfer line. The CHECKSUM format can be output with 4 (CS4) or 2 (CS2) hex numbers. The PTB220 calculates the checksum value of all the numbers set before the parameter CS4/CS2. >form 4.2 P " " CS4 #r#n ? > >send 994.
APPENDIX J ____________________________________________________PRESSURE TENDENCY APPENDIX J PRESSURE TENDENCY The World Meteorological Organization (WMO) publication Manual on Codes Vol. I.1, International Codes, Part A - Alphanumerical Codes, 1995 Edition, WMO - No. 306.
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.
APPENDIX L ____________________________________________________ SPECIAL EMULATION MODE APPENDIX L SPECIAL EMULATION MODE The PTB220 series digital barometers can partially emulate the PA11A and the Setra 470 digital barometers. To activate the desired emulation mode first turn the power off, then make the given switch selections and switch barometer on again. PA11A The PTB220 series digital barometers can partially emulate the PA11A digital barometers.
USER'S GUIDE_______________________________________________________________________ PaPaPaPaPa ppp NOTE Average pressure based on three consequent measurements of each transducer included, e.g. pressure average over approx. one minute. Three hour pressure trend. Replaced with status /// while data is not available, e.g. less than three hours measured. All pressure readings are in 0.1 hPa. The pressure unit selection has no effect.
APPENDIX L ____________________________________________________ SPECIAL EMULATION MODE Setra 470 A limited subset of commands is available provided that the switch SW7 is set as in FIGURE L-3.
USER'S GUIDE_______________________________________________________________________ The output after the -7777S command is: REF x.yy where the x.yy is the software version code. The output after the -8888SS test command is: D-NOS BUSY PASS or D-NOS BUSY ERR In order to exit the D-NOS mode, give the command C and the output is: VAISALA DIGITAL BAROMETER PTB 220 BUSY and then after a few seconds: VAISALA DIGITAL BAROMETER PTB 220 11.812 to 35.
APPENDIX M ________________________________________________ PRESSURE CONVERSION CHART APPENDIX M PRESSURE CONVERSION CHART Pressure conversion chart Multiplication factors TO Note: conversions for mmHg and inHg are defined at 0°C temperature and for mmH2O and inH2O at 4°C temperature. FROM hPa mbar Pa N/m2 mmHg torr inHg mmH2O inH2O atm at bar psia = psi absolute psi hPa mbar 1 0.01 1.333224 33.86388 0.09806650 2.490889 1013.25 980.665 1000 68.94757 Pa Nm2 100 1 133.3224 3386.
