SR50A-L
SR50A-L
RetiredSonic Distance Sensor
No longer available to order
This product is retained for service, documentation, and compatibility information.
Replaced by
- SnowVue 10
Digital Snow-Depth Sensor
- Model:
- SR50A-L
- Item Number:
- 19485
- Warranty:
- 2 years SN 6610+
Overview
The SR50A Sonic Distance Sensor provides a non-contact method for determining snow depth. It determines depth by emitting an ultrasonic pulse and then measuring the elapsed time between the emission and return of the pulse. An air temperature measurement is required to correct for variations of the speed of sound in air.
Note: Campbell Scientific recommends model SR50A-EE for operation in extreme environmental conditions where corrosion is a concern (such as coastal regions).
Key Advantages
Typically used for snow depth measurements
Technical Description
The SR50A was designed to meet the stringent requirements of measuring snow depth, and it uses a multiple echo processing algorithm to help ensure measurement reliability.
SDI-12, RS-232, and RS-485 output options are available for measuring the SR50A. Campbell Scientific’s MD485 interface can be used to connect one or more SR50A sensors in RS-485 mode to an RS-232 device. This can be useful for sensors that require lead lengths that exceed the limits of either RS-232 or SDI-12 communications.
The SR50A replaced the SR50 in March 2007. The newer SR50A is smaller and has different output options than its predecessor. The SR50AH is available with a heater option for locations where rime ice is a problem.
Product Notes
Benefits
- Wide operating temperature range
- User-selectable options for output
- Rugged enough for harsh environments
- Uses a multiple echo processing algorithm to help ensure measurement reliability
- Compatible with most Campbell Scientific data loggers
Specifications
- Measurement Description
- Snow depth
- Measurement Time
- < 1.0 s
- Measurement Range
- 0.5 to 10 m
(1.6 to 32.8 ft)
- Output Options
- SDI-12 version 1.3, RS-232, RS-485
(output options selected by configuring internal jumpers)
- Baud Rates
- 1200 to 38400 bps
(RS-232, RS-485 modes)
- Power Requirements
- 9 to 18 Vdc
(typically powered by data logger’s 12 Vdc power supply)
- Beam Acceptance
- ~30°
- Resolution
- 0.25 mm
(0.01 in.)
- Accuracy
- ±1 cm (0.4 in.) or 0.4% of distance to target (whichever is greatest).
Requires external temperature compensation.
- Operating Temperature Range
- -45° to +50°C
- Temperature Accuracy
- ±0.2°
(at 0° to 50°C)
±0.75°(at -45° to 0°C)
- Compliance
- CE Compliant
- Length
- 10.1 cm
(4.0 in.)
- Diameter
- 7.5 cm
(3 in.)
- Weight
- 375 g
(13.2 oz) without cable
1.0 kg(2.2 lb)
- Cable Weight
- 250 g
(8.2 oz) for a 4.57-m (15-ft) cable
Maximum Cable Length
- -NOTE-
- Cable lengths greater than 60 m require a heavier gage wire if the power supply drops below 11 Vdc.
- SDI-12
- 60 m
(200 ft)
- RS-232
- 60 m
(200 ft)
Baud rates ≤ 9600 bps - RS-485
- 300 m
(984 ft)
Power Consumption
- Active
- 250 mA
(typical)
- Quiescent SDI-12 Mode
- < 1.0 mA
- Quiescent RS-232/RS-485 Modes
- < 1.25 mA (≤ 9600 bps)< 2.0 mA (> 9600 bps)
Accessories
(9)19517
SR50A and SnowVue Mounting Kit
Orderable19484
SR50A and SnowVue Mounting Stem
Orderable17953
1- x 1-in. Nu-Rail Crossover Fitting
OrderableCM221
Right-Angle Mounting Kit
OrderableCM230
Adjustable Inclination Mounting Kit
OrderableCM230XL
Adjustable Angle Mounting Kit, Extended Length
Orderable33815
SDI-12 Terminal Bus Kit
Orderable39120
DIN Rail Terminal Kit with 2 Terminals and 5 Wires
Orderable39642
SDI-12 DIN Rail Terminal Bus Kit without Mounting Bracket
Orderable
Common Accessories
(8)19517
SR50A and SnowVue Mounting Kit
This mounting kit can be used as an alternative to the 19484 mounting stem. The 19517 attaches directly to CM206 crossarm or a user-supplied horizontal pipe with a 1" to 1.75" OD.
Orderable19484
SR50A and SnowVue Mounting Stem
The 19484 mounting stem attaches to the sensor. The stem is then attached to the CM206 crossarm via a CM220 mount, 17953 NU-RAIL fitting, or CM230 Adjustable Inclination Mount.
Orderable17953
1- x 1-in. Nu-Rail Crossover Fitting
The 17953 NU-RAIL Crossover Fitting can be used instead of the CM220 to attach the SR50A to a CM206 crossarm. The 19484 mounting stem is also required.
OrderableCM221
Right-Angle Mounting Kit
The CM221 mounts a pipe or tube at 90° to another pipe or tube. It is typically used to attach a sensor with a vertical pipe (including most wind sensors) to a crossarm. The cast aluminum, right-angle mounting bracket has 3.8 cm (1.5 in.) U-bolts and hardware and will accommodate tubing with a 1- to 1.5-in. outer diameter.
OrderableCM230
Adjustable Inclination Mounting Kit
If the surface is at an angle, the CM230 Adjustable Inclination Mount can be used to position the SR50A so that it is perpendicular to the ground.
OrderableCM230XL
Adjustable Angle Mounting Kit, Extended Length
The CM230XL provides the same functionality as the CM230, but the CM230XL places the SR50A further from the pole or crossarm.
Orderable39120
DIN Rail Terminal Kit with 2 Terminals and 5 Wires
The 39120 provides the needed DIN rail terminals, separator, and wires to connect any product to a data logger or other peripheral that requires five wires for connection. This kit provides the following wires: black, green, red, white, and clear. The color-coding of these wires matches the wire coloring of the product for ease in connection, maintenance, and troubleshooting.
Orderable39642
SDI-12 DIN Rail Terminal Bus Kit without Mounting Bracket
The 39642 makes it easier for you to connect wires from multiple SDI-12 sensors into one set of terminals on a data logger. The 39642 uses six DIN-rail mountable (pn 27479), 6-wire terminal blocks. The 39642 is a jumper that electrically connects two terminal blocks together at a time (pn 32918). This setup allows up to 11 SDI-12 sensors to be connected to one set of terminals on a data logger.
Orderable
Replacement Parts
(4)SR50ACBL
Replacement Cable for SR50A
This cable is available as a replacement item or as a "spare" cable. The SR50ACBL is fitted with a connector for attachment to the SR50A. On the other end, the cable terminates in pigtails for connection to the datalogger.
Orderable19486
SR50A or SR50AT Transducer Maintenance Kit
The 19486 provides one replacement transducer with connector, an O-ring, six #4091 desiccant bags, and two #905 desiccant bags. The transducer can typically be replaced in the field by the customer (assumes reasonably favorable weather conditions).
Orderable42816
1/2-Unit Desiccant Bags (quantity of 10)
The 42816 desiccant is used to desiccate small subassemblies. For example, the KH20 Krypton Hygrometer and the base of the CR3000 Measurement and Control Datalogger each require two bags. Multi-packs are recommended for customers who need to desiccate multiple enclosures or systems.
Orderable42945
1 g Bag of Desiccant (quantity of 10)
The 42945 consists of 10 1-g bags of desiccant for drying the air in the area above an instrument. Six bags of the desiccant are used to dry the air in the area above the transducer. Purchase of additional bags is recommended to use as spares or to rotate bags with time.
Orderable
Ships With
(2)- Test Report
SR50ACBL
Replacement Cable for SR50A
Orderable
Similar Products
(5)SR50AT
Sonic Distance Sensor with Temperature Sensor
Limited availabilitySR50ATH
Sonic Distance Sensor with Heater and Temperature Sensor
Limited availabilitySR50AH
Heated Sonic Distance Sensor
Limited availabilitySR50A-EE
Anodized Sonic Distance Sensor for Extreme Environments
Limited availabilitySnowVue 10
Digital Snow-Depth Sensor
Orderable
Compatibility
Compatible Products
(3)CR310
Measurement and Control Datalogger
OrderableNotesSDI-12 and RS-232. For RS-485, requires an MD485 interface or similar RS-485 to RS-232 interface.
CR6
High-Capacity Data Acquisition System
OrderableNotesSDI-12, RS-232, and RS-485
CR350
Measurement and Control Datalogger
OrderableNotesSDI-12 and RS-232. For RS-485, requires an MD485 interface or similar RS-485 to RS-232 interface.
Related Resources
Case Studies
Documents
- Manual
SR50A-Series Sonic Ranging Sensors
September 2021
View Document - Document
SnowVue 10 and SR50A Product Comparison
October 2022
View Document - Compliance
SR50A FCC Supplier Declaration of Conformity and FCC Statement
April 2020
View Document - Brochure
SR50A Sonic Ranging Sensor
March 2026
View Document
Showing 4 of 6 results
See all DocumentsDownloads
- OS and FirmwareSR50A/AT OSv1.3
August 22, 2007
Current SR50A / AT firmware.
- Software ApplicationsSR50A example programsv1
January 22, 2020
CR6 and CR1000X programs that directly read each type of SR50A output (SDI-12, RS-232, RS-485), and a CR1000 program that reads the RS-485 output using an MD485 Multidrop interface. A 107 sensor provides the temperature measurement needed for temperature compensation. The programs use the data filtering method described in the manual.
Videos and Tutorials
Services Available
- Repair
- Yes
- Free Support
- Yes


