User manual VAISALA PTB200

[. . . ] SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 1 (28) PTB200-O0284-1. 1 PTB 200 DIGITAL BAROMETERS 1 PRODUCT DESCRIPTION 2 2 INSTALLATION 2. 1 2. 2 2. 3 2. 4 2. 5 2. 6 2. 7 Mounting Grounding Power connections Serial output mode connections Pulse output mode connections Pressure connections Multiple barometers on one RS 232C bus 3 3 4 5 6 7 8 9 3 SERIAL COMMANDS 3. 1 General 3. 2 Configuration commands 3. 3 Operating commands 10 10 11 19 4 ADJUSTMENT AND CALIBRATION 4. 1 Offset and gain adjustment 4. 2 Multipoint adjustment 22 23 24 5 TECHNICAL DATA 26 Appendix 1 Commands PTB200 Digital Barometer Appendix 1 SERIAL COMMANDS Function serial bus settings echo on/off output format pressure resolution units integration time settling time/response time sending mode address defining single output command sleep mode list of software settings starting output stopping output output single reading setting output interval control of a single barometer in POLL mode resetting error messages linear pressure adjustment multipoint correction Command SERI ECHO FORM FORM UNIT MTIM, FILT MTIM, FILT SMODE ADDR SCOM SLEEP ?R S SEND INTV OPEN , CLOSE RESET ERRS LP MPC, MPCI Comment STOP, RUN and POLL modes for POLL mode only in STOP and RUN modes only in POLL mode address required 1994-08-16 1 SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 2 (28) PTB200-O0284-1. 1 1 PRODUCT DESCRIPTION The PTB 200 A and PTB 201 A are fully compensated digital barometers designed to operate over a wide pressure and temperature range. The final factory adjustment and calibration of the PTB 200 A is done against a deadweight tester for best accuracy and pressure traceability. The PTB 201 A is adjusted and calibrated by using electronic working standards to meet the requirements of demanding weather station applications. [. . . ] Type the selected pressure unit as given above. Example of changing the pressure unit to mbar: >UNIT mbar<cr> MTIM Setting the measurement time parameters MTIM<cr> The MTIM command is used to set the number of measurement samples (MTIM value) integrated to get a pressure reading. The basic measurement sample time is about 25 milliseconds. The MTIM factory setting of the PTB 200 A is 64; this ensures a stable resolution of 0. 01 hPa. The integration time is then 64 x 25 ms = 1600 ms. The settling time including initialization and integration time is approximately 2 s. The MTIM factory setting of the PTB 201 A is 16; this ensures a stable resolution of 0. 1 hPa. The integration time is then 16 x 25 ms = 400 ms. The settling time including initialization and integration time is approximately 1 s. The MTIM value affects the settling time of the barometer: the longer the integration time, the longer the settling time. The FILT command also affects the integration and settling times (see FILT command). Example of changing the MTIM value: >MTIM<cr> Mtim : 64 ?150<cr> SSD/Operating Manual PTB 200 Digital Barometers 24th February 1993 15 (28) PTB200-O0284-1. 1 FILT Setting the filter parameters FILT xxx yyyy<cr> where xxx ON or OFF yyyy FAST or SLOW The FILT command is used to set additional numerical filtering modes. FAST mode introduces a multiplication factor of 4 to the integration time set with the MTIM command. In addition a special algorithm that takes the derivative of the pressure change into account is used. SLOW mode introduces a multiplication factor of 16 to the integration time set with the MTIM command. No derivative of the pressure change is taken into account. The filter settings also affect the settling time of the barometer. Example of setting the integration time to 5 seconds (MTIM 50, filter FAST): >MTIM<cr> Mtim : 64 ?50<cr> >FILT ON FAST<cr> Press. filter : ON FAST Example of setting the integration time to 60 seconds (MTIM 150, filter SLOW): >MTIM<cr> Mtim : 50 ?150<cr> >FILT ON SLOW<cr> Press. [. . . ] (set second pressure level and enter value here)<cr> P : (the current non-corrected value appears here) Use ESC to abort without executing a command. Return the MEMORY jumper to the EEPROM write disable position. 4. 2 Multipoint pressure adjustment MPC OFF Multipoint correction off MPCI Multipoint correction input MPC ON Multipoint correction on MPC OFF<cr> MPCI<cr> MPC ON<cr> The MPC/MPCI commands are used in multipoint pressure adjustment at up to eight pressure levels. If a new fine adjustment is needed, the previous multipoint corrections must first be omitted with the MPC OFF command. Writing down the previous multipoint corrections is recommended as they will be lost when MPCI command is used. [. . . ]