1. Total Precipitation Gauge (TPG)
12/19/13

2. Overview TPG, Single Cell TPG-0001-1
Sutron’s Total Precipitation Gauge (TPG) is a weighing bucket gauge with a built-in logger designed for remote measurement of precipitation. The TPG can be equipped with multiple load sensors for added redundancy and reliability. Sutron designed the TPG using technology proven in the NWS Fischer Porter Rebuild kit program. Instead of refurbishing an ageing Fischer Porter Gauge, many users will find it easier to simply replace with Sutron’s TPG. 
TPG, Single Cell
TPG

3. TPG Applications Hydro-Met monitoring systems Municipal hydrology
Flood warning systems
Stormwater monitoring networks
Water balance models
Watershed and catchment basin studies
Climate change studies
Tropical and arctic monitoring
Tipping bucket upgrades
Replacement of Fischer/Porter gauges
CRN -- Climate reference network
AWS – automatic weather stations
ASOS/AWOS – Automated Weather Observing System (airports)
NWS Co-op modernization

4. TPG Features
Measures all forms of precipitation: drizzle, rain, sleet, snow, graupel, and hail.
Optional Wind Shield to increase catchment of precipitation – studies show that gauges without shields miss 25-50% of solid precipitation in windy environments.
No moving parts – greater reliability and lower maintenance (less clogging) than tipping buckets.
Optional heater – eliminates capping of the sensor in heavy snows or areas with riming ice (requires line power).
High capacity – 36” (914mm) precipitation – with option to expand range to 72” or higher using auto-drain.
Based on NWS Precip Gauge Upgrade technology being used in over 1000 stations.
SDI-12 interface to Satlink, IridiumLink, GPRS/CDMALink or other loggers
WMO compliant (manual 306, No 8)
Built-in logger for data redundancy to station logger, or can act as a standalone logging sensor.
Low power consumption (<1ma standby) for long life of battery.
NIST traceable factory calibration with simple field verification/calibration.
Simple mounting on 4.5” OD pipe

5. TPG Specifications
Measurements: Precipitation, Precip rate, Internal Temp, Battery
Automeasure Interval : 1 second to 24 hours
Measurement Technique: Precision hermetically sealed load cell
Accuracy: 0.02" (0.6mm) -25°C to +60°C
Range: 36" (914 mm) standard, >72" (1800 mm) with optional drain kit
Enclosure: UV Resistant ABS plastic Cover, 8" diameter aluminum inlet with knife edge. Cast aluminum base with 4" pipe mount (for 4.5" OD pipe)
Communication Ports: SDI-12, RS232
Operating Temperature: -40°C to +60°C
Built-In Flash Memory: 4 MB (>300,000 readings)
Clock Accuracy (at 0°C – 40°C): 20 seconds per month
Power Requirements: VDC
Current Drain: VDC standby, 5ma active
Communication Protocols: MODBUS, SDI-12

6. TPG Operation Theory & Components
8” diameter opening allows all types precipitation to fall into the collection bucket
Optional heater keeps opening free from snow and ice
Oil layer reduces evaporation
Antifreeze in bucket melts snow/ice
Precision load cell weighs the precipitation
Electronics convert weights into precipitation amounts, logs data, and sends data to main station logger/telemetry
Optional drain kit empties bucket when it precipitation reaches 70% capacity
Mounts on 4.5” OD pipe

7. Windscreen Benefits
WMO is testing the TPG in the Solid Precipitation Inter-Comparison Experiment (SPICE).
TPG3 with Alter shield catches 25-50% more than TPG1 without shield.
Windscreen Example

8. Client Portfolio – U.S.A USACE USGS National Park Service
Bureau of Reclamation

9. Client Portfolio – International
WMO
Hoskin Scientific
Anyone else?

10. Installation Examples
Master Station
Demo Station – Sutron Headquarters Rooftop, Sterling VA

11. Installation Examples
Gated Weather Station with TPG - Kabul, Afghanistan

12. Installation Examples
TPG in Bulgaria

13. Installation Examples
???, Alaska

14. Installation Examples
WMO’s Solid Precipitation Inter-Comparison Experiment (SPICE) – Marshall, Colorado

15. TPG Models & Options Models Options TPG-0001-1 TPG, single cell
TPG TPG, triple cell
Options
TPG-DK TPG Drain Kit
TPG-HK TPG Heater kit, 120V, 200W
TPG-HK TPG Heater kit, 240V,200W
TPG-HK TPG Heater kit, 48V, 200W
TPG-WS-36-GA TPG Windscreen - Galvanized
TPG-WS-36-SS TPG Windscreen - Stainless Steel
TPG-WS-48 TPG Windshield, 48” diameter
WS-24-EXT-GA Windscreen Extension - Galvanized
WS-24-EXT-SS Windscreen Extension - Stainless Steel