Additel ADT209 is a compact loop calibrator designed for testing, troubleshooting and calibrating industrial 4–20 mA process loops. Combining current measurement, current sourcing and transmitter simulation with DC voltage measurement, 24 V loop power, an integrated 250 Ω HART resistor and advanced ramp and step functions, the ADT209 provides the essential tools required by process technicians and calibration professionals in one portable instrument.

With an accuracy of up to 0.03% of reading, the Additel ADT209 provides reliable performance for a wide variety of process calibration and maintenance applications. Current can be measured and sourced from 0 to 24 mA with a resolution of 1 µA, while DC voltage can be measured from 0 to 30 V with a resolution of 1 mV.

A particularly useful feature is the simultaneous display of the measured current in mA and the corresponding percentage of the 4–20 mA span. This allows technicians to evaluate process signals quickly without manually converting current values into percentages.

The integrated 24 V loop power supply can power two-wire transmitters directly during testing. A built-in 250 Ω HART resistor further simplifies work on process loops where an appropriate loop resistance is required for HART communication.

Automatic ramp and step functions, direct zero and span selection and switch testing make the ADT209 a versatile tool for field service, maintenance, commissioning and calibration.

At europascal, we provide professional solutions for process measurement, electrical calibration and pressure calibration. The Additel ADT209 is an excellent choice for technicians who require a compact and easy-to-use instrument for everyday work on industrial current loops.

For professional calibration and metrological traceability of the Additel ADT209 and other electrical measuring instruments, use the europascal Calibration Service.

Your Benefits at a Glance

The Additel ADT209 combines the essential functions required for testing and calibrating industrial process loops in a compact handheld instrument.

Key benefits include:

• Current measurement from 0 to 24 mA
• Current sourcing from 0 to 24 mA
• Current simulation for externally powered loops
• Current resolution of 1 µA
• Accuracy up to 0.03% of reading
• DC voltage measurement from 0 to 30 V
• Voltage resolution of 1 mV
• Simultaneous mA and percentage display
• Integrated 24 V loop power supply
• Integrated 250 Ω HART resistor
• Automatic ramp function
• Automatic step function
• Direct zero and span selection
• Switch test function
• Compact handheld design
• Weight of approximately 350 g
• Long battery operating time
• Suitable for field and laboratory applications
• ISO/IEC 17025 accredited calibration with data supplied by Additel

Professional 4–20 mA Loop Calibration

The Additel ADT209 has been developed specifically for working with industrial process loops.

The 4–20 mA current signal remains one of the most widely used analog transmission standards in industrial measurement and process control.

Transmitters convert physical quantities such as:

• Pressure
• Temperature
• Flow
• Level
• Humidity
• Force

into a standardized electrical current signal.

In a typical process loop:

4 mA represents 0%

and:

20 mA represents 100%

of the configured measurement range.

The Additel ADT209 can measure, source and simulate these signals, making it possible to test different components of a process control loop systematically.

Current Measurement from 0 to 24 mA

The Additel ADT209 measures DC current from:

0 to 24 mA

with a resolution of:

1 µA

The specified accuracy is:

0.03% of reading + 2 µA

under the manufacturer’s specified reference conditions.

The 24 mA upper limit provides sufficient margin above the standard 20 mA endpoint of a conventional process loop.

This makes the ADT209 suitable for measuring output signals from pressure transmitters, temperature transmitters and other process instruments.

Current Source from 0 to 24 mA

The Additel ADT209 can also generate a defined current signal.

The source range is:

0 to 24 mA

with a resolution of:

1 µA

and a specified accuracy of:

0.03% of reading + 2 µA.

This function can be used to test devices that receive and process a current signal.

Typical applications include:

• Process indicators
• PLC analog inputs
• Controllers
• Data acquisition systems
• Recorders
• Control systems

Instead of connecting a real transmitter, the ADT209 generates the required process signal directly.

Transmitter Simulation

The Additel ADT209 can simulate a transmitter in an externally powered current loop.

In this operating mode, the calibrator controls the current supplied by the external loop power source.

Additel specifies an external loop voltage range from approximately:

12 V to 30 V

for this function.

Transmitter simulation is particularly useful when testing the receiving side of a process control loop without connecting the actual transmitter.

This makes troubleshooting considerably easier because different sections of the signal chain can be tested independently.

DC Voltage Measurement up to 30 V

In addition to current measurement and generation, the Additel ADT209 measures DC voltage from:

0 to 30 V

with a resolution of:

1 mV.

The specified accuracy is:

0.03% of reading + 2 mV.

Voltage measurement can be used to check power supplies and electrical signals within a process loop.

Combining voltage and current measurement in one compact device reduces the number of instruments technicians need to carry during field service.

Simultaneous mA and Percentage Display

A particularly convenient feature of the Additel ADT209 is the simultaneous display of current and percentage values.

For a standard 4–20 mA process signal, technicians can immediately see both the electrical current and its corresponding percentage of span.

For example:

4 mA = 0%

8 mA = 25%

12 mA = 50%

16 mA = 75%

20 mA = 100%

This eliminates the need for manual calculations and simplifies transmitter adjustment, troubleshooting and functional testing.

Integrated 24 V Loop Power

The Additel ADT209 includes an integrated:

24 V loop power supply

This allows compatible two-wire transmitters to be powered directly by the calibrator during testing.

An additional external power supply is therefore unnecessary for many common process calibration tasks.

This reduces the number of instruments and cables required when performing field calibration.

The feature is particularly useful for technicians working directly at industrial installations.

Integrated 250 Ω HART Resistor

The ADT209 also includes an integrated:

250 Ω resistor

for use with the 24 V loop power supply.

An appropriate loop resistance is required when digital HART communication is superimposed on the conventional 4–20 mA signal.

The integrated resistor simplifies the setup of a suitable loop when an external HART communication device is used.

The ADT209 itself should primarily be considered a precision loop calibrator rather than a full HART communicator.

Automatic Ramp Function

The Additel ADT209 includes an automatic ramp function.

Instead of manually changing the output current, the calibrator can continuously vary the signal over the selected range.

This makes it easy to observe how a connected instrument responds as the process signal changes.

Typical applications include checking:

• Analog indicators
• Process displays
• PLC inputs
• Controllers
• Recorders
• Data acquisition systems

The automatic ramp function is particularly useful for identifying irregularities across the complete measurement range.

Automatic Step Function

An automatic step function is also available.

The output current is changed automatically between predefined points.

This provides a fast and convenient method of checking several points across a 4–20 mA range.

Typical calibration points can include:

0%, 25%, 50%, 75% and 100%

of the measurement span.

The technician can therefore concentrate on the response of the device under test instead of manually adjusting the calibrator for every individual test point.

Zero and Span Function

The Additel ADT209 provides convenient access to zero and span values.

This is particularly useful when adjusting process transmitters.

For a conventional 4–20 mA transmitter, the lower and upper range values can be selected quickly to check the two most important adjustment points.

This can significantly reduce the time required for routine transmitter checks.

Switch Test Function

The Additel ADT209 also provides a switch test function.

This allows technicians to verify the switching behavior of suitable electrical and process devices.

Applications can include:

• Limit switches
• Pressure switches
• Temperature switches
• Process alarms
• Relay contacts

The function expands the ADT209 beyond conventional current loop testing and provides additional flexibility for industrial maintenance applications.

Compact and Lightweight Design

Portability is an important advantage of the Additel ADT209.

The instrument measures only approximately:

163 × 83 × 41 mm

and weighs approximately:

350 g.

Its compact dimensions make it easy to carry in a service case or tool bag.

This is particularly useful for technicians who work at multiple measurement locations throughout a production facility.

Designed for Field Applications

The Additel ADT209 is designed for both laboratory and field applications.

Additel specifies an operating temperature range of:

-10 °C to 50 °C

and operation at relative humidity levels up to:

95% RH

within the manufacturer’s specified conditions.

The instrument is also designed to withstand the mechanical demands associated with mobile use.

Its combination of compact dimensions and robust construction makes it suitable for industrial service and maintenance environments.

Long Battery Operating Time

The Additel ADT209 is powered by a standard 9 V alkaline battery.

Typical operating time is approximately:

18 hours in source mode

at the manufacturer’s specified operating conditions and approximately:

50 hours in measurement mode.

This provides sufficient operating time for extended field service applications without requiring frequent battery replacement.

An external power adapter is also available for applications where the calibrator is used for longer periods at a fixed workstation.

Typical Applications

The Additel ADT209 is suitable for a wide variety of process measurement and calibration applications.

Typical applications include:

• 4–20 mA loop calibration
• Process transmitter testing
• Pressure transmitter calibration
• Temperature transmitter testing
• PLC input testing
• Process indicator calibration
• Controller testing
• Loop troubleshooting
• Commissioning
• Preventive maintenance
• Electrical signal verification
• Switch testing

This broad range of applications makes the ADT209 a useful everyday tool for calibration and maintenance technicians.

Additel ADT209 Compared with ADT210

The Additel ADT209 and Additel ADT210 provide very similar loop calibration functionality.

The primary difference is their accuracy class.

The ADT209 provides accuracy down to:

0.03% of reading

while the ADT210 provides higher accuracy down to:

0.01% of reading.

The ADT209 is therefore an attractive solution for general service, maintenance and routine calibration applications where the higher accuracy of the ADT210 is not required.

For more demanding metrological applications, the ADT210 provides additional accuracy while retaining the compact operating concept of the series.

ISO/IEC 17025 Accredited Calibration

Additel supplies the ADT209 with an ISO/IEC 17025 accredited calibration certificate including measurement data.

This provides documented calibration information for the electrical functions of the instrument.

Regular calibration is essential for maintaining confidence in the measurement results of process and electrical calibration equipment.

At europascal, we provide professional calibration services for a wide variety of measurement and calibration equipment.

For further information about calibration services and metrological traceability, visit the europascal Calibration Service.

Technical Highlights

Why Choose the Additel ADT209?

The Additel ADT209 combines the essential functions required for testing industrial 4–20 mA loops in a compact and easy-to-use handheld instrument.

Current can be measured, sourced or simulated from 0 to 24 mA with 1 µA resolution, while DC voltage measurement up to 30 V allows additional electrical checks to be performed within the process loop.

The integrated 24 V loop power supply eliminates the need for a separate power supply in many transmitter calibration applications.

An integrated 250 Ω HART resistor simplifies the setup of process loops where external HART communication equipment is used.

Automatic ramp and step functions reduce manual work during functional testing, while the simultaneous display of mA and percentage values makes 4–20 mA signals easier to evaluate.

With dimensions of only 163 × 83 × 41 mm and a weight of approximately 350 g, the ADT209 is particularly suitable for mobile calibration, commissioning, troubleshooting and maintenance.

Its accuracy of up to 0.03% of reading provides an attractive balance between measurement performance and cost for routine process calibration applications.

At europascal, we provide professional solutions for process measurement and calibration technology. We can assist you in selecting suitable Additel calibration equipment and accessories for your individual application.

For professional calibration and metrological traceability of the Additel ADT209 and other electrical measurement equipment, visit the europascal Calibration Service.

Discover more Additel products at europascal.

Manufacturer information about the Additel ADT209 is available on the official Additel website.

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