The InSitu TROLL System Interface

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The In-Situ TROLL System Interface

• May, 2006

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In-Situ System Interface

• Compatible products with TROLL system interfaces
• Overview of TROLL family system interfaces and
  Rugged Connection system
• Discuss RS-485 Modbus interface and networking
• Discuss SDI-12 interface and networking
• Discuss 4-20mA current loop interface
• Questions?
• Summary

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Compatible Products with TROLL System Interface

• Level TROLL 700
• Level TROLL 500
• Level TROLL 300
• Baro TROLL
• All future TROLL devices

New TROLL products utilize the new system
interface
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System Interface Features

• Rugged Connection System
• Modbus RS485 Serial Interface
• SDI-12 Serial Digital Interface
• 4 to 20 mA Current Loop
• External Power
• Atmospheric Vent System

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Rugged Connection System

• Backshells
• Cables
• Cable extenders
• Desiccant cartridges
• Interface adapters
• Network adapters
• Battery packs

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Modbus RS485

• Modbus RS485 is a widely recognized industry
  standard
• RS485 is the electrical specification defining
  the physical interface
• Modbus is the protocol specification that defines
  how data is communicated over the interface

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Modbus RS485 Features

• Native mode for TROLL devices and Win-Situ
  software
• Longest cable lengths up to 4000 feet (1200
  meters)
• Fastest data rates up to 57600 baud
• Best noise immunity
• Network support

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Basic Standalone Connection
TROLL
Rugged Cable
TROLL Com
Win-Situ

• Temporary connection
• Membrane protected venting
• No desiccant protection
• No external power

• 9600 baud to 4000 ft (1200 m)
• 19200 baud to 4000 ft (1200 m)
• 38400 baud to 1500 ft (450 m)
• 57600 baud to 1000 ft (300 m)

Soon USB TROLL Com w/o external power Later
USB RS232 TROLL Coms w/external power
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Basic Standalone Deployment
TROLL
Rugged Cable
Desiccant

• Long-term deployment
• Membrane protected venting
• Desiccant protection
• No need to retrieve device for download and
  programming

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Backshell Deployment
Programming Cable
TROLL
Backshell
Win-Situ

• Deployed
• Long-term deployment
• Absolute pressure only
• No venting support
• Lowest cost

• Programming
• Must retrieve device for download and programming
• Temporary connection
• No vent protection
• External 12 volt power

USB RS232 TROLL Com Programmers w/external power
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Basic PLC Connection
Female Stripped Tinned Cable
PLC
TROLL

• Simplest connection, lowest cost
• Permanent installation
• Desiccant protected venting
• External power from PLC (12 or 24 VDC)
• PLC samples and logs on its own schedule
• Customer needs Modbus register map information
  sheet
• Difficult to disconnect for calibration or
  download of backup logs

Optional
Programming Cable
Win-Situ
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Enhanced PLC Connection
PLC
TROLL
Rugged Cable

• Permanent installation
• Desiccant protected venting
• External power from PLC
• PLC samples and logs on its own schedule
• Easy to disconnect for calibration and download

Bulkhead Connector or Male Stripped Tinned Cable
TROLL Com
Win-Situ
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TROLL Net Basics

• Built with TROLL Net accessories
• Maximum of 32 TROLLs on a net
• Maximum total cable length of 4000 ft (1200 m)
• Network must be properly terminated with a 120
  ohm resistor at each end

TROLL Net Adapter is already available TROLL Net
Junction coming soon
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TROLL Net Connections
TROLL Net Junctions
PLC
T
T
1x
1x
1x
Rugged Cable
2x
2x
2x
TROLL Net Adaptor
TROLL
TROLL Com
Win-Situ
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Configuring a TROLL Net Device

• Each device on the network requires a unique
  device address.
• All devices on the network must share the same
  communication settings.
• Devices should be configured before adding them
  to the network.

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Win-Situ on a TROLL Net
A precaution when using Win-Situ to access
devices on a TROLL Net Always disconnect from a
device before changing the device address.
Otherwise Win-Situ will reprogram the address of
the connected device, potentially leaving the
network with multiple devices having the same
address. If this happens, the device must be
removed from the network and reconfigured.
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Modbus Transmission Modes

• RTU
• Compact packets
• Faster transfers
• Timing sensitive
• Direct connections

• ASCII
• Larger packet sizes
• Slower transfers
• Not timing sensitive
• Wireless links
• Com port adapters

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External Power Considerations

• 36 Volts DC maximum at the source
• 8 Volts DC minimum at the device
• Cable loss must be considered
• LevelTROLL 1 Volt per 1000 ft (300 m)
• 12 Volt systems to 1000 ft
• 24 Volt systems beyond 1000 ft

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External Battery Systems
Desiccant
TROLL
Rugged Cable
Battery Pack
TROLL Com
Male Stripped Tinned Cable
TROLL
Rugged Cable
External Battery Charger
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SDI-12 Serial Digital Interface

• An industry standard for interfacing data
  recorders with microprocessor-based sensors.
• Large installed base with USGS, HIF,
  municipalities.
• Many data recorders installations implement
  wireless communication and gateways.

• Some popular data recorder manufacturers
• Campbell Scientific
• ISCO
• Sutron
• Global Water

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SDI-12 Features

• Cable lengths to 200 feet (60 meters)
• Fixed data rate 1200 baud
• Poor noise immunity
• Data recorder supplies power to sensor
• Recorder samples and logs on its own schedule
• Network support

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SDI-12 Implementation

• Fully support version 1.3 of the standard
• Easy configuration via Win-Situ
• Provide extended commands for configuration via
  the data recorder
• Support ISCO extended commands for automated
  configuration

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Basic SDI-12 Connection
Data Recorder
Female Stripped Tinned Cable
TROLL

• Simplest connection, lowest cost
• Permanent installation
• Desiccant protected venting
• External power from data recorder (12 volts DC)
• Recorder samples and logs on its own schedule
• Customer needs SDI-12 command information sheet
• Difficult to disconnect for calibration or
  download of backup logs

Optional
Programming Cable
Win-Situ
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Enhanced SDI-12 Connection
Data Recorder
TROLL
Rugged Cable

• Permanent installation
• Desiccant protected venting
• External power from data recorder
• Recorder samples and logs on its own schedule
• Easy to disconnect for calibration and download

Bulkhead Connector or Male Stripped Tinned Cable
TROLL Com
Win-Situ
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SDI-12 Networks
Data Recorder

• Maximum of 10 TROLLs on a net
• Maximum total cable length of 200 ft (60 m)
• Star and backbone topologies OK
• Cannot build SDI-12 network with TROLL Net
  accessories

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SDI-12 Configuration
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SDI-12 Configuration
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4 to 20 mA Current Loop

• Analog Output
• Moderate noise immunity
• Cable lengths up to 4000 feet (1200 meters)
• Only one parameter from one sensor
• Programmable scaling

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Basic 4-20 mA Connection
Female Stripped Tinned Cable
PLC
TROLL

• Simplest connection, lowest cost
• Permanent installation
• Desiccant protected venting
• External power from PLC (24 VDC)
• PLC samples and logs on its own schedule
• Difficult to disconnect for calibration or
  download of backup logs

Programming Cable
Win-Situ
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Enhanced 4-20 mA Connection
PLC
TROLL
Rugged Cable

• Permanent installation
• Desiccant protected venting
• External power from PLC
• PLC samples and logs on its own schedule
• Easy to disconnect for calibration and download

Bulkhead Connector or Male Stripped Tinned Cable
TROLL Com
Win-Situ
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4-20 mA Loop Power
24 VDC recommended for most applications

• 8 volts minimum at device
• 1 volt per 1000 ft (300 m)
• 5 volt typical PLC overhead

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4-20 mA Configuration