Endress+Hauser TM401 Specifications

TI01058T/09/EN/04.18 71419895 2018-03-30

Products

Solutions Services

Technical Information

iTHERM TM401

Resistance thermometer for hygienic and aseptic applications

Metric version with basic technology for all standard applications, permanent insert

Applications

• Specially designed for use in hygienic and aseptic applications in the Food & Beverages and Life Sciences industries

• Measuring range: –50 to +200 °C (–58 to +392 °F)

• Pressure range up to 50 bar (725 psi)

• Protection class: up to IP69K

• Can be used in non-hazardous areas

Head transmitter

All Endress+Hauser transmitters are available with enhanced accuracy and reliability compared to directly wired sensors. Easy customizing by choosing one of the following outputs and communication protocols:

Analog output 4 to 20 mA, HART

Your benefits

• Excellent value for money and fast delivery

• User-friendly and reliable from product selection to maintenance

• International certification: hygiene standards as per 3-A®, EHEDG, ASME BPE, FDA, TSE Certificate of Suitability

• Wide range of process connections

Function and system design

inch

iTHERM TM401

iTHERM Hygiene line

This thermometer is part of the product line of modular thermometers for hygienic and aseptic applications.

Differentiating factors when selecting a suitable thermometer

TM4x1 TM4x2

Metric version Imperial version

↓ ↓

TM41x characterizes the device that uses cutting-edge technology, with features such as a replaceable insert,

quick-fastening extension neck (iTHERM QuickNeck), vibration-resistant and fast-response sensor technology

(iTHERM StrongSens and QuickSens) and approval for use in hazardous areas

TM411

TM412

↓ ↓

TM40x characterizes the device that uses basic technology, with features such as a fixed, non-replaceable

insert, application in non-hazardous areas, standard extension neck, low-cost unit

TM401

Measuring principle Resistance thermometer (RTD)

These resistance thermometers use a Pt100 temperature sensor according to IEC 60751. The temperature sensor is a temperature-sensitive platinum resistor with a resistance of 100 Ω at 0 °C (32 °F) and a temperature coefficient α = 0.003851 °C-1.

A0018239

A0018692

A0018691

TM402

A0018693

2 Endress+Hauser

iTHERM TM401

Commubox

FieldCare

PLC

°C

There are generally two different kinds of platinum resistance thermometers:

• Wire wound (WW): Here, a double coil of fine, high-purity platinum wire is located in a ceramic support. This is then sealed top and bottom with a ceramic protective layer. Such resistance thermometers not only facilitate very reproducible measurements but also offer good long-term stability of the resistance/temperature characteristic within temperature ranges up to 600 °C (1 112 °F). This type of sensor is relatively large in size and it is comparatively sensitive to vibrations.

• Thin film platinum resistance thermometers (TF): A very thin, ultrapure platinum layer, approx. 1 μm thick, is vaporized in a vacuum on a ceramic substrate and then structured photolithographically. The platinum conductor paths formed in this way create the measuring resistance. Additional covering and passivation layers are applied and reliably protect the thin platinum layer from contamination and oxidation, even at high temperatures.

The primary advantages of thin film temperature sensors over wire wound versions are their smaller sizes and better vibration resistance. A relatively low principle-based deviation of the resistance/ temperature characteristic from the standard characteristic of IEC 60751 can frequently be observed among TF sensors at high temperatures. As a result, the tight limit values of tolerance category A as per IEC 60751 can only be observed with TF sensors at temperatures up to approx. 300 °C (572 °F). For this reason, thin-film sensors are generally only used for temperature measurements in ranges below 400 °C (752 °F).

Measuring system

Endress+Hauser offers a complete portfolio of optimized components for the temperature measuring point – everything you need for the seamless integration of the measuring point into the overall facility. This includes:

• Power supply unit/barrier

• Display units

• Overvoltage protection

For more information, see the brochure 'System Components - Solutions for a Complete Measuring Point' (FA00016K/EN)

A0017693

 1 Example of application, measuring point layout with additional Endress+Hauser components

Installed iTHERM resistance thermometer with integrated HART® head transmitter

2 RIA16 field display unit - The display unit records the analog measuring signal from the head transmitter and

shows this on the display. The LC display shows the current measured value in digital form and as a bar graph indicating a limit value violation. The display unit is looped into the 4 to 20 mA circuit and gets the required energy from there. More information on this can be found in the Technical Information, see "Documentation", →  26.

3 Active barrier RN221N - The RN221N (24 V DC, 30 mA) active barrier has a galvanically isolated output for

supplying voltage to loop-powered transmitters. The universal power supply works with an input supply voltage of 20 to 250 V DC/AC, 50/60 Hz, which means that it can be used in all international power grids. More information on this can be found in the Technical Information, see "Documentation", →  26.

Endress+Hauser 3

Input

iTHERM TM401

Measured variable

Measuring range

Output signal

Family of temperature transmitters

Temperature (temperature-linear transmission behavior)

Sensor type Measuring range

Pt100 thin-film –50 to +200 °C (–58 to +392 °F)

Output

Generally, the measured value can be transmitted in one of two ways:

• Directly-wired sensors - sensor measured values forwarded without a transmitter.

• Via all common protocols by selecting an appropriate Endress+Hauser iTEMP temperature transmitter. All the transmitters listed below are mounted directly in the terminal head and wired with the sensory mechanism.

Thermometers fitted with iTEMP transmitters are an installation-ready complete solution to improve temperature measurement by significantly increasing accuracy and reliability, when compared to direct wired sensors, as well as reducing both wiring and maintenance costs.

PC programmable head transmitters

They offer a high degree of flexibility, thereby supporting universal application with low inventory storage. The iTEMP transmitters can be configured quickly and easily at a PC. Endress+Hauser offers free configuration software which can be downloaded from the Endress+Hauser Website. More information can be found in the Technical Information.

HART® programmable head transmitters

The transmitter is a 2-wire device with one or two measuring inputs and one analog output. The device not only transfers converted signals from resistance thermometers and thermocouples, it also transfers resistance and voltage signals using HART® communication. It can be installed as an intrinsically safe apparatus in Zone 1 hazardous areas and is used for instrumentation in the terminal head (flat face) as per DIN EN 50446. Swift and easy operation, visualization and maintenance by PC using operating software, Simatic PDM or AMS. For more information, see the Technical Information.

Advantages of the iTEMP transmitters:

• Dual or single sensor input (optionally for certain transmitters)

• Unsurpassed reliability, accuracy and long-term stability in critical processes

• Mathematical functions

• Monitoring of the thermometer drift, sensor backup functionality, sensor diagnostic functions

• Sensor-transmitter matching for dual sensor input transmitter, based on Callendar/Van Dusen coefficients

Wiring

• According to the 3-A® Standard electrical connecting cables must be smooth, corrosionresistant and easy to clean.

• Grounding or shield connections are possible via special ground terminals on the terminal head.

4 Endress+Hauser

iTHERM TM401

RTD

3-wire

4-wire

Power supply head transmitter and analog output 4 to 20 mA, or bus connection

(red) (red) (red) (red)

(white) (white)

(white)

1 x Pt 100

red

white

4 wires 3 wires

red

white

red

white

1 BN 2 GNYE 3 BU 4 GY

4 3

Wiring diagrams for RTD

Type of sensor connection

Head mounted transmitter TMT18x (single input)

A0016433-EN

Terminal block mounted

Cable entries

Connector

Endress+Hauser 5

See the 'Terminal head' section

PIN assignment of the M12 connectors, connection combinations

Electrical connection (terminal head)

1x TMT 4 to 20 mA or

Connector M12 connector 4‐pin

PIN number 1 2 3 4

Flying leads Not connected (not insulated)

3-wire terminal block

(1x Pt100)

RD RD

4-wire terminal block

(1x Pt100)

HART

+ i - i

WH WH

PIN position and color

code

A0019262-EN

A0018929

iTHERM TM401

Abbreviations

i RD WH BN GNYE BU GY

Insulated

1) Wires marked 'i' are not connected and are insulated with heat shrink tubes.

Red White Brown Green-

yellow

Blue Gray

Overvoltage protection

Reference conditions

Accuracy

To protect against overvoltage in the power supply and signal/communication cables for the thermometer electronics, Endress+Hauser offers the HAW562 surge arrester for DIN rail mounting and the HAW569 for field housing installation.

For more information see the Technical Information 'HAW562 Surge arrester' TI01012K and 'HAW569 Surge arrester' TI01013K.

Performance characteristics

These data are relevant for determining the accuracy of the temperature transmitters used. More information on this can be found in the Technical Information of the iTEMP temperature transmitters. →  26

RTD resistance thermometer as per IEC 60751

Class Max. tolerances (°C)

Cl. AA, former 1/3 Cl. B ± (0.1 + 0.0017 · |t|

Cl. A ± (0.15 + 0.002 · |t|)

Cl. B ± (0.3 + 0.005 · |t|)

Temperature range for compliance with the tolerance classes

Thin-film version (TF): Cl. A –30 to +200 °C

)

6 Endress+Hauser

iTHERM TM401

-200 -100 0 100 200 300 400 500 600°C

0.5

1.0

1.5

2.0

2.5

3.0

- 0.5

- 1.0

- 1.5

- 2.0

- 2.5

- 3.0

Max. deviation (°C)

Characteristics

1) |t| = absolute value °C

In order to obtain the maximum tolerances in °F, the results in °C must be multiplied by a factor of 1.8.

Influence of ambient

Depends on the head transmitter used. For details, see Technical Information. →  26

temperature

Self heating

RTD elements are passive resistances that are measured using an external current. This measurement current causes a self-heating effect in the RTD element itself which in turn creates an additional measurement error. In addition to the measurement current, the size of the measurement error is also affected by the temperature conductivity and flow velocity of the process. This selfheating error is negligible when an Endress+Hauser iTEMP temperature transmitter (very low measured current) is used.

Response time

Tests in water at 0.4 m/s (1.3 ft/s), according to IEC 60751; 10 K temperature step change.

Pipe diameter

6 mm (¹⁄₄ in)

8 mm (0.31 in)

Reduced 4.5 mm (0.18 in)x

Reduced 5.3 mm (0.21 in) x

Response time without transmitter.

1x Pt100 thin-film sensor

Shape of tip

Response time

Straight 5 s 11 s

18 mm (0.71 in)

20 mm (0.79 in)

3.5 s 9 s

5 s 10.5 s

A0008588-EN

Endress+Hauser 7

iTHERM TM401

Calibration

Insulation resistance

Calibration of thermometers

Calibration involves comparing the measured values of a device under test (DUT) with those of a more precise calibration standard using a defined and reproducible measurement method. The aim is to determine the deviation of the DUT's measured values from the true value of the measured variable. Two different methods are used for thermometers:

• Calibration at fixed-point temperatures, e.g. at the freezing point of water at 0 °C,

• Calibration compared against a precise reference thermometer. The thermometer to be calibrated must display the fixed point temperature or the temperature of

the reference thermometer as accurately as possible. Temperature-controlled calibration baths with very homogeneous thermal values, or special calibration furnaces are typically used for thermometer calibrations. The measuring uncertainty may increase due to heat conduction errors and short immersion lengths. The existing measuring uncertainty is recorded on the individual certificate of calibration. For accredited calibrations in accordance with ISO17025, a measuring uncertainty that is twice as high as the accredited measuring uncertainty is not permitted. If this limit is exceeded, only a factory calibration is possible.

For the device, Endress+Hauser offers standard calibrations at a reference temperature of –50 to +200 °C (–58 to +392 °F) based on the ITS90 (International Temperature Scale). Calibrations in other temperature ranges are available from your Endress+Hauser sales center on request. Calibrations are traceable to national and international standards. The calibration certificate is referenced to the serial number of the thermometer.

Insulation resistance ≥ 100 MΩ at ambient temperature.

Insulation resistance between the terminals and the outer jacket is measured with a minimum voltage of 100 V DC.

Orientation

Installation instructions

Installation

No restrictions. However, self-draining in the process must be guaranteed. If there is an opening to detect leaks at the process connection, this opening must be at the lowest possible point.

The immersion length of the thermometer can influence the accuracy. If the immersion length is too small then errors in the measurement are caused by heat conduction via the process connection and the container wall. If installing into a pipe then the immersion length should ideally be half of the pipe diameter.

• Installation possibilities: Pipes, tanks or other plant components

• To minimize the error caused by heat conduction, a minimum immersion length, which corresponds to the calibration, is recommended depending on the type of sensor used.

8 Endress+Hauser

iTHERM TM401

≥ 3°

1 2

A0008946

 2 Installation examples

1, 2 Perpendicular to flow direction, installed at a min. angle of 3° to ensure self-draining 3 On elbows 4 Inclined installation in pipes with a small nominal diameter U Immersion length

In the case of pipes with a small nominal diameter, it is advisable for the tip of the thermometer to project well into the process so that it extends past the pipe axis. Installation at an angle (4) could be another solution. When determining the immersion length or installation depth all the parameters of the thermometer and of the medium to be measured must be taken into account (e.g. flow velocity, process pressure).

 3 Process connections for thermometer installation in pipes with small nominal diameters

Varivent® - process connection D = 50 mm for DN25 pipes

2 Clamp or micro-clamp

A0018881

Endress+Hauser 9

+ 19 hidden pages