Name: KEYILE科译勒 K-DPT Differential Pressure Transmitter
Brand: KEYILE SHOP
SKU: K-DPT
Availability: InStock
Rating: 5 (1 reviews)

Description
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Working Principle

一、 The figure below is the basic working principle electrical block diagram of the smart transmitter. The working principle and functions of each component will be described below.

Transmitter principle block diagram

二、Intelligent circuit board

1) A/D conversion: The A/D conversion circuit uses a dedicated low-power integrated circuit to convert the analog current output by the demodulator into a digital quantity with an accuracy of up to 18 bits, which is provided to the microprocessor processor as input signal.

2) Microprocessor: The microprocessor of the smart transmitter controls the A/D and D/A conversion work, and can also complete self-diagnosis and realize digital communication. When working, a digital pressure value is processed by the microprocessor and stored as a digital value to ensure precise correction and conversion of engineering units. In addition, the microprocessor can also complete the linearization, range ratio, damping time and other function settings of the sensor.

3) EEPROM memory: EEPROM stores all configuration, characterization and digital fine-tuning parameters. This memory is non-volatile, so even if the power is off, the stored data can still be kept intact to realize intelligent communication at any time.

4) D/A conversion: D/A conversion converts the calibrated digital signal sent by the microprocessor into a 4- 20mA analog signal and outputs it to the loop

5) Digital communication: Transmitters with HART protocol can test and configure smart transmitters through a communicator. Or complete communication through any upper system host that supports HART communication protocol. The HART protocol uses the industrial standard BELL202 frequency shift keying (FSK) technology to achieve communication by superimposing a 1200Hz or 2000Hz digital signal on a 4-20mA signal. During communication, the frequency signal does not interfere with the 4-20mA process. Transmitters without HART protocol can be tested and configured with dedicated adapters and software.

6) Display and buttons: Smart transmitters with LCD display can display the pressure value, current value, 0%- 100% proportional display and temperature value of the sensor measured by the transmitter, and the transmitter can be configured through the buttons on the LCD panel.

Smart transmitters without display can also perform operations such as zeroing and active calibration on the transmitter through the S and Z buttons on the line panel.

Product Features

◆ gh precision and excellent stability

◆ Two-wire system (special models available in four-wire)

◆ Compact, lightweight, and rugged vibration-resistant design

◆ No moving mechanical parts, ensuring high reliability and easy maintenance

◆ Unified structure across the full series, with strong component interchangeability

◆ Explosion-proof construction, suitable for all-weather operation

◆ Smart HART fieldbus protocol support

◆Self-diagnosis and remote diagnostic capabilities

Application Field

Differential pressure transmitter is a kind of measuring equipment widely used in various fields, mainly used to measure the pressure difference of liquid or gas and convert it into standard signal output. Its main application areas include: Oil and gas industry: monitoring the liquid level and pressure changes inside the oil tank to control the flow in and out of the oil tank; measuring the flow of oil and gas in land, offshore and submarine applications; Water and sewage treatment: used to monitor filters in sewage treatment plants; Power industry: used to monitor water sprinkler systems and steam or hot water heating systems; Metallurgical industry: used to monitor pressure drop on valves and pump control; Gas analysis field: used to monitor gas composition and pressure changes in boilers or burners, monitor steam or gas flow in steam turbines or gas turbines, such as gas generators, gas flow control, gas pressure measurement in furnace front instruments and filter differential pressure detection, etc.

Application Field


Differential pressure transmitter	Side mounted single flange	Double flange type	Insertion tube type

Technical Specification

Range of use	Liquids, gases and vapours.
Measurement range	See Table 1.
Signal output	Two-wire 4-20mA isolated DC signal superimposed on HART digital signal output, linear or square root output can be selected, and the maximum output current does not exceed 22mA.
Power supply	DC 12~45V; HART communication: 15.5~45V DC; normal working voltage: 24VDC.
Load range	When communicating with HART, the resistance in the power supply loop should be ≥250 ohms and the power supply voltage should be ≥15.5 volts.
Communication distance	The diameter of the connecting wire is greater than 0.6mm and the communication distance is approximately 1500 meters.
Display	Intelligent LCD 5.5-digit digital + backlight (white/green optional) display; combined use of F1, F2 and F3 buttons on the LCD display, the display can cyclically or fixedly display: kPa, mA, ﹪, ℃, mmH2O, MPa, Pa, mbar, atm, psi, Torr engineering units, can achieve no pressure to modify the measurement range (passive migration), set fixed current output, modify damping time, set linear, square root output and backup and restore data and other functions.
Zero position and range migration	The lower limit of the measuring range is not lower than the lower limit of the maximum measuring range, and the upper limit is not higher than the upper limit of the maximum measuring range, that is, the working range does not exceed the limit value of the sensor, and the zero position and range can be set at any corresponding point of 4-20mA.
Zero pressure fine adjustment	Refer to the button instructions for steps.
Damping value	Electronic damping adjustable range: 0 to 32 seconds.
Magnification factor	It can be adjusted within the range of 1 to 128 times as needed.
Fault alarm	When the self-diagnostic routine detects a fault, the analog output is above 20.8mA or below 3.9mA.
Data recovery	When data is damaged, it can be restored on-site with three buttons.
Temperature compensation	The computer collects temperature data and sends it to the transmitter for temperature compensation.
Temperature indication	Indicates the ambient temperature of the field where the transmitter is working.
Working temperature	-40～85℃, with LCD display: -35～85℃.
Storage temperature	－45～90℃.
Safety protection	AND circuit protection design, anti-static shock, surge current, and overload protection are powerful.

Table 1 Measurement range andaccuracy

Pressure Type	Measurement Range	Accuracy Level
DP、GP	(0—0.16~1)kPa	Level 0.1 Level 0.2 Level 0.5 Level 1.0
DP、HP GP、AP	(0—1~6)kPa
	(0-6~40)kPa
	(0-40~200)kPa
	(0-0.16~1)MPa
	(0-0.4~2.0)MPa
GP	(0-1.6~10)MPa
	(0-4~20)MPa
	(0-6~40)MPa

Table 2 Basic error after migration

Accuracy level	Basic error/%
0.1	±0.2
0.2	±0.4
0.5	±1.0
1.0	±2.0

Table 3 Transmitter temperature coefficient

Accuracy level	emperature Accuracy level coefficient/%FS/10℃
0.1	±0.1
0.2	±0.2
0.5	±0.5
1.0	±1.0

Technical Specification

Basic error	±0.075％、0.1％、0.2％
End base consistency error	±0.1％、0.2％、0.3％
Repeatability error	0.1％、0.2％、0.3％
Backlash	0.1％、0.2％、0.3％
Stability	Within the range, the basic error shall not exceed within one year.
Anti-interference characteristics	Add 1～100kHz, peak 1～380VAC variable frequency interference signal to the power supply and housing, 4～20mA output,change <±0.2%
Temperature effect	For DP and GP types, the range code is 4～8, the error is <±0.15%/10℃, the maximum range limit; for other types and other ranges, the error is doubled.
Constant current performance	Change < 0.075%.
Insulation performance	Power supply to ground resistance ﹥400MΩ.
Response time	When powered on, the response time is <2 seconds
Sensitivity	Lower limit and range change < 0.01%.
Power supply voltage change	Lower limit and range change < 0.02%
Steady-state change	Power supply interrupted for a short time, change < 0.02%
Over range	Overrange: lower limit and range change < 0.05%
Static pressure error	DP class, for 14MPa, lower limit change < ±0.3%; HP class, for 32MPa, lower limit change < ±0.5%
External magnetic field effect	In 400A/m (root mean square) magnetic field, change < 0.05%
Mechanical vibration	Vibration frequency: 50Hz, full amplitude: 0.2mm, 2 hours of vibration, residual lower limit and range change < 0.075%
Installation position effect	When the sensor center measuring diaphragm is not vertical, a zero position system error of no more than 0.24kPa may be generated, but this error can be eliminated by adjusting the zero pressure fine-tuning, and has no effect on the range
Structural material	Material of parts in contact with the medium such as pressure chamber, joint, relief valve, isolation diaphragm
Pressure connection	The connection hole on the pressure chamber is 1/4-18NPT, and the connection hole on the pressure connector is 1/2-14NPT. The center distance can be changed by adjusting the connector.
Electrical connection	The transmitter housing has two M20×1.5 screw holes for connecting the cable conduit. There are wiring terminals and test pads inside the housing. When connecting to a communicator, it can be fixed on the test pads.
Volume absorption	Volumetric absorption: < 0.16 cm2

KEYILE科译勒 K-DPT Differential Pressure Transmitter

Description

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