General introduction of HQ-3051 series capacitive transmitter

HQ-3051 series capacitive transmitter product overview

The HQ-3051 series miniaturized capacitive pressure (differential pressure) transmitter is a new type of transmitter produced by our factory through the introduction of advanced foreign technology and equipment. The key raw materials, components, and parts are all imported, and the whole machine has undergone strict assembly and testing. This product has the characteristics of advanced design principles, complete varieties and specifications, and easy installation and use. At the same time, it can directly replace traditional 1151 and other well-known similar products, with strong universality and substitution ability. In order to adapt to the continuous improvement and development of domestic automation level, this series of products not only has a compact and exquisite design, but also introduces intelligent functions with HART fieldbus protocol.

Characteristics of HQ-3051 series capacitive transmitter

◆ High precision

◆ Good stability

◆ Two wire system (special four wire system is available)

Solid components, plug-in printed circuit boards

◆ Small, lightweight, sturdy and vibration resistant

◆ Range and zero point can be continuously adjusted externally

Positive migration can reach 500%; Negative transfer can reach 600%

◆ Adjustable damping

◆ Good one-way overload protection characteristics

◆ No mechanical movable parts, low maintenance workload

◆ Unified structure across the entire series, with strong interchangeability of components

The membrane material in contact with the medium can be selected from corrosion-resistant materials such as 316L, TAN, HAS-C, MONEL, etc

Explosion proof structure, all-weather use

◆ Intelligent HART fieldbus protocol

Working principle of HQ-3051 series capacitive transmitter

The process pressure is transmitted to the center measuring diaphragm of the delta chamber through the isolation diaphragm on both sides or one side, and filled with liquid. The central diaphragm is a tensioned elastic element that produces corresponding deformation displacement in response to the pressure difference acting on it on both sides. Its displacement is proportional to the differential pressure, with a maximum displacement of about 0.1mm. This displacement transformation forms a differential capacitor on the capacitor plate, which is converted into a two-wire 4-20mADC signal output by electronic circuits.

HQ-3051 series capacitive transmitter functional parameters

Target audience: liquids, gases, and vapors

Measurement range: 0~0.1kPa to 0~40MPa

Output signal: 4~20mADC (special for four wire 220V power supply, 0~10mADC output)

Power supply: 12~45V DC, usually 24V DC (see load characteristics in the figure)

Load characteristics: Related to the power supply, the load capacity at a certain power supply voltage is shown in the figure (load characteristics), and the load impedance RL is related to the power supply voltage V. The relationship equation is: RL ≤ 50 (Vs-12)

Indicator: pointer type linear indication with 0~100% equal division scale or LCD liquid crystal display, LED digital tube display.

Explosion proof: a. Explosion proof type dIIBT4

b. Intrinsically safe iaIICT6

Range and zero point: externally continuously adjustable

Positive and negative transfer: After the zero point undergoes positive or negative transfer, the excellent values of the upper and lower limits of the range and measurement range cannot exceed 100% of the upper limit of the measurement range. (Intelligent type: Range ratio 15:1)

*The large positive transfer is 500% of the small calibration range, and the large negative transfer is 600% of the small calibration range.

Temperature range: Amplifier operating temperature range: -29~+93 ℃ (LT type: -25-+70 ℃)

Measuring element filled with silicone oil: -40~+104 ℃

When filling high-temperature silicone oil into flange type transmitters: -20~+315 ℃, ordinary silicone oil: -40~+149 ℃, static pressure: 1, 4, 10.25, 32Mpa

Humidity: Relative humidity is 0~100%

Volume suction capacity:<0.16cm3

Damping (step response): When filled with silicone oil, it is generally continuously adjustable between 0.2s and 1.67s

Technical data of HQ-3051 series capacitive transmitter

(Without migration, under standard working conditions, filled with silicone oil, 316 stainless steel isolation diaphragm)

Accuracy: Soil 0.1%, Soil 0.2%, Soil 0.5%, (Intelligent)

Dead zone: None (≤ 0.1%)

Stability: Within six months, the basic error of the large range should not exceed the excellent value

Vibration effect: In any axial direction, when the vibration frequency is 200Hz, the error is+0.05%/g of the upper limit of the measurement range

Power supply impact: less than 0.005% V of the output range

Load impact: If the power supply is stable, the load is not affected

HQ-3051 series capacitive transmitter Other

Isolation membrane: 316 stainless steel, Hastelloy C-276, Monel alloy or tantalum

Exhaust/Drain Valve: 316 Stainless Steel, Hastelloy C, Monel Alloy

Flanges and fittings: 316 stainless steel, Hastelloy C or Monel alloy

Contact medium "O" ring: nitrile rubber, fluororubber

Filling fluid: silicone oil or inert oil

Bolt: 316L stainless steel

Electronic casing material: low copper aluminum alloy

Pressure connector: flange NPT1/4, Center distance 54mm; joint NPT1/2 or M20X1.5 male threaded ball cone seal, with a center distance of 50.8.54 when equipped with a joint 57.2mm (NPT taper pipe thread in accordance with GB/T12716-91) signal line connection hole: G 1/2 "

Weight: 2.4kg
Outline dimensions and installation connection diagram

Schematic diagram of pressure connection joint