SBW Series Temperature Transmitter

Key Features

• Single-loop connection
• Single-indicator connection
• Multi-loop connection
• Calibration method for RTD temperature transmitters
• Calibration method for thermocouple temperature transmitters

Technical Specifications

The SBW series thermocouple / RTD temperature transmitter is a field-mounted temperature transmitter unit in the DDZ series instrument family, used together with industrial thermocouples and RTDs. It adopts a 2-wire transmission mode (the two wires serve both as power input and as the common signal output line). It converts industrial thermocouple and RTD signals into a 4–20 mA or 0–10 mA output signal that is linear with respect to the input signal or to the temperature.

The transmitter can be installed directly inside the terminal head of the thermocouple or RTD to form an integrated structure. As a new generation of temperature measuring instrument it is widely used in metallurgy, petroleum, chemical, power, light industry, textile, food, defence and scientific research sectors.

Main features

1. Sealed with silicone rubber or epoxy resin, it is therefore vibration-proof and moisture-proof and suitable for installation in harsh field environments,

2. Field-mounted for use inside the terminal head of a thermocouple or RTD, directly outputting 4–20 mA or 0–10 mA signals.

This both saves the cost of expensive extension wires and improves the anti-interference capability during long-distance signal transmission,

3. The thermocouple transmitter has automatic cold-junction temperature compensation,

4. High accuracy, low power consumption, wide ambient temperature range, stable and reliable operation,

5. Wide applicability: it can form an integrated field-mounted structure with thermocouples or RTDs, and can also be installed as a functional module in detection equipment or on instrument panels,

6. The intelligent temperature transmitter can communicate with a host computer via a HART modem, or with a hand-held terminal and PC, for remote information management, configuration, variable monitoring, calibration and maintenance of the transmitter model, graduation No. and range,

7. The intelligent temperature transmitter allows the display orientation to be adjusted according to actual user requirements, and can display the measured medium temperature, the change in sensor value, the output current and the percentage ratio,

Operating Principle

The measured temperature is converted by the thermocouple or RTD sensor into an electrical signal, which is then fed into the input network of the transmitter; this network contains circuits for zero adjustment and thermocouple compensation. After zero adjustment the signal is fed into an operational amplifier for amplification. One path of the amplified signal is processed by a V/I converter and output as a 4–20 mA DC current, while the other path is processed by an A/D converter and sent to the local display. The transmitter has two types of linearisation circuit, both using feedback. For RTD sensors, positive feedback correction is used,

For thermocouple sensors, correction is performed using a multi-segment broken-line approximation method. The integrated digital display temperature transmitter has two display modes. LCD-display temperature transmitters use a 2-wire output, while LED-display temperature transmitters use a 3-wire output.

Technical Specifications

1. Input signal: thermocouple: K, E, J, B, S, T, N. RTD: Pt100, Cu100, Cu50 (3-wire, 4-wire). The input signal of the intelligent temperature transmitter can be set freely via PC or hand-held terminal,

2. Output signal: within the measuring range it outputs a 4–20 mA DC signal that is linear with respect to the input signal of the thermocouple or RTD, or linear with respect to temperature. The intelligent temperature transmitter outputs a 4–20 mA DC signal with a superimposed communication signal conforming to the HART protocol,

The isolated temperature transmitter has its input and output isolated with an isolation voltage of 0.5 kV, improving common-mode interference rejection and making it more suitable for computer networking applications,

3. Basic error: 0.5% FS, 0.2% FS, intelligent type 0.2% FS;

4. Wiring method: 2-wire, 3-wire, 4-wire,

5. Display mode: a 4-digit LCD displays the field temperature; the intelligent 4-digit LCD can be set via PC or hand-held terminal to display any one of the field temperature, sensor value, output current and percentage ratio,

6. Operating voltage: standard type 12 V–35 V, intelligent type 12 V–45 V, rated operating voltage 24 V;

7. Permissible load resistance: 500 Ω (24 V DC supply); maximum load resistance R(max) = 50 (Vmin – 12). For example, at the rated operating voltage of 24 V, the load resistance can be selected within the range of 0–600 Ω.

8. Operating environment:

a: Ambient temperature -25 to 80 °C (standard type)

-25 to 70 °C (digital type)

-20 to 75 °C (intelligent type)

b: Relative humidity: 5%–95%

c: Mechanical vibration f ≤ 50 Hz, amplitude ≤ 0.15 mm

d: Environment free of corrosive gases or similar,

g: Temperature influence coefficient: δ ≤ 0.05% / °C;

Measuring Range

Model code & description

System connection

Temperature indicator Transmitter

Temperature indicator Transmitter

Temperature indicator Transmitter

Outline dimensions of the SBW signal converter

Calibration method

○ When used in hazardous explosive areas, please note the Ex marking and degree of protection,

○ The mechatronic temperature transmitter must be installed in an ambient temperature between -20 °C and 70 °C. When the surrounding temperature is too high, the XPZX signal converter and display module can be installed separately from the thermocouple or RTD (our factory supplies a dedicated flameproof enclosure for separated installation);

○ Before power-on, carefully check the positive and negative polarity of the power supply; incorrect connection may cause unpredictable consequences,

○ The XPZX signal converter and display module are potted and cured with epoxy resin to enhance vibration resistance and provide protection against moisture, corrosion and humidity,

○ The temperature transmitter shall be calibrated after six months of service.

Equipment required: one 4-digit voltmeter one 0.01 Ω–1 kΩ resistance box

One 250 Ω wire-wound precision resistor One 24 V DC regulated power supply

○ Wire the unit according to the system connection method

○ According to the sensor and range marked on the transmitter nameplate, input the corresponding resistance value so that the output is 1 V and 5 V respectively (adjustable via the zero and span potentiometers)

○ Input each resistance value at the ten equal division points of the range and check that the output at each temperature point is within the accuracy range

○ Test item by item against the technical specifications in the manual; all items shall meet the requirements

Equipment required: one 4-digit voltmeter one UJ33a potentiometer

One 250 Ω wire-wound precision resistor One 24 V DC regulated power supply

○ Wire the unit according to the system connection method

○ According to the sensor and range marked on the transmitter nameplate, input the corresponding EMF so that the output is 1 V and 5 V respectively (adjustable via the zero and span potentiometers)

○ Input each resistance value at the ten equal division points of the range and check that the output at each temperature point is within the accuracy range

○ Test item by item against the technical specifications in the manual; all items shall meet the requirements

Ordering information

○ Special specification orders can be decided by mutual agreement

○ Protection tubes of the corresponding material, such as corundum or high-alumina, can be supplied according to user requirements.

○ If other special requirements apply, please state them when ordering.

Ordering & Inquiry

For selection guidance, specification confirmation or quotation, please call 0512-57892201, Mobile 13451695112, or submit an online order. Suzhou Dingluxuan Sensor Technology Co., Ltd. provides a complete matching service from temperature sensing elements to complementary ceramic insulation parts.

To order this product or get selection guidance, please call +86 512-57892201 or submit an online order.