Integrated digital temperature transmitter
Integrated digital temperature transmitter
SBWR , SBWZ series thermocouples and RTD temperature transmitters are field-mounted temperature transmitter units in DDZ series meters. They are used with industrial thermocouples and thermal resistors. They use two-wire transmission method (two wires as power supply Common transmission line for input and signal output). The industrial thermocouple, thermal resistance signal is converted into a 4-20mA , 0-10mA output signal that is linear with the input signal or with the temperature signal .
The temperature transmitter can be directly installed in the junction box of thermocouples and thermal resistors to form an integrated structure. As a new generation of temperature measuring instrument, it can be widely used in metallurgy, petroleum, chemical, electric power, light industry, textile, food, national defense and scientific research industries.
The main features of integrated digital temperature transmitter
· Silicone rubber or epoxy seal structure, so shock, moisture, suitable for installation in harsh environments.
· It is installed in the junction box of thermocouples and thermal resistors on site and outputs 4-20mA and 0-10mA output signals directly . This not only saves the cost of the expensive compensation wire, but also improves the anti-interference ability of the signal during long-distance transmission.
·The thermocouple transmitter has automatic cold junction temperature compensation;
High precision, low power consumption, wide operating temperature range, stable and reliable operation;
Wide range of applications, which can be combined with thermocouples, thermal resistors to form an integrated field installation structure, and can also be used as functional modules installed in the testing equipment and on the instrument panel;
Intelligent Temperature Transmitter HART modem can communicate with the host computer or handheld device and the PC model of the transmitter, indexing number, range information for remote management, configuration, variable monitoring, calibration and maintenance functions;
Intelligent temperature transmitter can adjust the display direction of the user actually needs the transmitter, temperature transmitter and display medium measured, the sensor value changes, and the percentage of the output current;
Integrated digital temperature transmitter working principle
A thermocouple or RTD sensor converts the measured temperature into an electrical signal, which is then fed into the transmitter's input network. The network contains the relevant circuitry such as zeroing and thermocouple compensation. By zeroing the signal input to the operational amplifier for signal amplification, the amplified signal is calculated all the way through V / I converter worked up to 4 - 20mA DC current output; another path the A / D converter to process the meter display. There are two types of transmitter linearization circuits, all using feedback. Thermistor sensors are calibrated with positive feedback, and thermocouple sensors are calibrated with multisection polyline approximation. The integrated digital display temperature transmitter has two display modes. The temperature transmitter of the LCD display is output in a two-wire system, and the temperature transmitter of the LED display is output in a three-wire system.
Integrated digital temperature transmitter technical parameters
1, the input signal: Thermocouple: K, E, J, B , S, T, N. Thermal resistance: Pt100 , Cu50 ,
Cu100 ( three-wire system, four-wire system ) . The input signal of the intelligent temperature transmitter can be arbitrarily set by the handset and the PC ;
2, the output signal: in output within the range 4 - 20mA current signal, the input signal into a linear thermocouple or RTD or linear with temperature. Intelligent temperature transmitter outputs 4 - 20mA DC signal simultaneously superimposed and communicated with HART standard protocol; Isolated temperature transmitter: Input and output isolation, isolation voltage 500V , increased resistance to common mode interference, more suitable for connecting with computer Web use;
3 , the basic error: 0.5% FS , 0.2% FS , intelligent 0.2% FS ;
4. Connection mode: two-wire system, three-wire system, four-wire system;
5. Display mode: four-digit LCD display on-site temperature, intelligent four-digit LCD can be set by PC or handheld to display any parameters in the field temperature, sensor value, output current and percentage;
6 ã€Working Voltage: Ordinary Model 12V-35V , Intelligent 12V-45V , Rated Operating Voltage 24V
7. Permissible load resistance: 500Ω ( 24VDC supply); limit load resistance R ( max ) = 50 (Vmin-12). For example, when the rated working voltage is 24V , the load resistance can be selected within the range of 0-600Ω .
8 , working environment: a: ambient temperature -25-+80 °C (conventional)
-25-+70 °C (digital display type)
-25-+75 °C (Smart)
b: Relative humidity: 5%-95%
c: mechanical vibrations f≤50Hz, amplitude ≤0.15mm
d: No corrosive gas or similar environment;
9, the environmental impact factor: δ≤0.05% / ℃.
Temperature range of integrated digital temperature transmitter
Category
Materials
Index number
Measuring range
Thermocouple
Nickel-Chromium - Constantan
E
0-1000 °C optional
Nickel-Chromium - Nickel Silicon
K
0-1300 °C optional
Platinum rhodium 10- platinum
S
0-1600 °C range
Platinum crucible 30- platinum crucible 6
B
Optionally in the range of 0-1800 ℃
Copper - Connor
T
0-400 °C optional
Iron - Connor
J
Optional from 0-1200 °C
Thermal resistance
Copper thermal resistance
Cu50
-50-+150 °C optional
Copper thermal resistance
Cu100
-50-+15 °C optional
Platinum thermal resistance
Pt100
-200-+600 °C optional
Model code and description: ( with transmitter sensor selection see temperature transmitter (explosion-proof) thermocouple / resistance )
model
Instructions
SBW
Temperature Transmitter
category
R
Thermocouple
Z
Thermal resistance
sensor
1
Adaptable K -type thermocouple / thermal resistance adapter Pt100
2
Fit E -type thermocouple / thermal resistance fit Cu100
3
Adaptable J type thermocouple / thermal resistance fitting Cu50
4
Adaptable type B thermocouple
5
Adapt S type thermocouple
6
Fit T thermocouple
7
Adapting type N thermocouple
8
User defined
Circuit category
0
Isolated type
1
Non-isolated
Installation method
0
Conventional type
1
Special type
2
Wall type
3
Rail type
Temperature Transmitter
0
Conventional type
1
smart
2
Digital display type
3
Pointer type
4
Intelligent digital display
5
Smart Pointer
6
With HART protocol type
Wiring and adjustment
The wiring principle of the transmitter is shown in the figure. Terminal 4 is connected to the positive terminal of the 24V power supply, and terminal 3 is the current output terminal of 4 to 20mA . This terminal returns to the negative terminal of the 24V power supply after the load resistor R1 .
Terminals 1 and 2 are connected with a thermal resistor, or 2 is connected with a thermocouple positive, and 1 is connected with a thermocouple negative. Transmitters have zero and span adjustment potentiometers for easy user adjustment.
Calibration method:
· When used in explosion hazardous locations, please note the explosion-proof signs and protection levels;
The mechatronic temperature transmitter must be installed within -20-+70 °C . When the ambient temperature is too high, the SBWZ/R signal converter and display module can be installed separately from the RTD or thermocouple. Our factory is equipped with a special explosion-proof box for separating and installing the transmitter.
• Before powering on, please check the positive and negative polarity of the power supply carefully. Do not connect it incorrectly, otherwise it may cause unknowable consequences.
· The SBW signal converter module is potted and cured with epoxy resin to enhance its shockproof performance and prevent moisture, corrosion and moisture.
• The temperature transmitter must be calibrated after six months of use.
a , thermal resistance temperature transmitter calibration method
· Equipment requirements: a digital voltmeter;
· Connect according to system connection method;
· According to the sensor and range indicated on the transmitter's nameplate, input the corresponding resistance value, make the output 1V and 5V (the zero potentiometer and full-scale potentiometer can be adjusted separately);
• Input each resistance value according to ten divisions of the range and check whether each temperature output meets the accuracy range;
· Test according to specification specifications, should meet the technical requirements.
b , thermocouple temperature transmitter calibration method
· Equipment requirements: a digital voltmeter;
· Connect according to system connection method;
· According to the sensor and range indicated on the transmitter's nameplate, input the corresponding resistance value to make the output 1V and 5V respectively (the zero potentiometer and full-scale potentiometer can be adjusted separately);
· Input each potential value according to ten divisions of the range and check whether each temperature output meets the accuracy range;
· Test according to specification specifications, should meet the technical requirements.
Baby Bowl,Stainless Steel Bowl,Stainless Steel Tableware,Bowl For Children
Ningbo Jiuxin International Trade Co., Ltd. , https://www.cnnbjiuxin.com