Vaisala WS425 - Manual (Page 5)

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VAISALA ________________________________________________________________________ 5
Impedance........................................................................... 52
SDI-12 Communications Protocol ....................................... 53
Baud Rate and Byte Frame Format .................................... 53
Two Different Submodes..................................................... 54
Standard SDI-12 Commands Supported by WS425 .......... 55
Acknowledge Active Command (a!)............................... 55
Send Identification Command (aI!) ................................ 56
Address Query Command (?!) ....................................... 56
Change Address Command (aAb!)................................ 57
Start Measurement Command (aM!) ............................. 58
Send Data Command (aD0!) ......................................... 58
Continuous Measurements (aR0!) ................................. 60
Start Verification (aV!) .................................................... 61
Vaisala-specific SDI-12 Commands Supported by WS425 62
Measurement Unit Change (aXUx!)............................... 62
Heater Control Command (aXHx!)................................. 63
Check Current Submode (aX?!)..................................... 63
Place Sensor in Submode B (aXQx;c.c;n;yyyy!)............ 64
Reset the Sensor to Submode A Command (aXS!) ...... 65
Check Current Measurement Unit (aX*!) ....................... 65
SDI-12 TIMING ................................................................... 66
CHAPTER 5
MAINTENANCE ........................................................................................... 69
Visual Inspection of WS425 Ultrasonic Wind Sensor......... 69
Periodic Testing ..................................................................... 71
CHAPTER 6
TROUBLESHOOTING ................................................................................. 73
Common Problems ................................................................ 73
Frequently Asked Questions (FAQ) .................................... 73
Instructions for Opening a Serial Terminal Connection to
WS425................................................................................. 75
Technical Support .................................................................. 76
Return Instructions ................................................................ 76
Vaisala Service Centers......................................................... 77
CHAPTER 7
TECHNICAL DATA ...................................................................................... 79
Specifications ......................................................................... 79
APPENDIX A
DRAWINGS .................................................................................................. 81