Pressure & Temperature Transmitter

Product Overview

An industrial pressure and temperature transmitter integrates piezoresistive/capacitive pressure sensing elements with RTD (Pt100/Pt1000) or thermocouple temperature inputs into a single housing. Designed for dual-parameter monitoring in harsh industrial loops, it eliminates separate tapping points, reduces installation footprint, and transmits linearized 4-20 mA signals with superimposed HART protocol directly to DCS or PLC systems.

Compact Pressure Transmitter
Widely used for gauge and absolute pressure measurement in sectors such as petroleum, chemical engineering, wastewater treatment, constant-pressure water supply, environmental protection,...
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Industrial Temperature Transmitter
This high-performance industrial temperature transmitter is a sophisticated assembly designed for precise and reliable temperature monitoring across various industrial sectors. Housed in a robust...
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4-20mA Pressure Transmitter
Precision industrial pressure transmitter with 316L diaphragm, anti-interference, explosion-proof for harsh environments.

● High precision up to 0.1% FS
● Dual explosion-proof...
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Smart Differential Pressure Transmitter
Our Smart Differential Pressure Transmitter is engineered for demanding applications requiring precise measurement of differential pressure, flow, and liquid level.

● High Accuracy &...
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RTD Temperature Sensor
This high-performance industrial temperature transmitter is a sophisticated assembly designed for precise and reliable temperature monitoring across various industrial sectors.

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Fixed Type Pressure Transmitter
Our Industrial Pressure Transmitter delivers exceptional performance and reliability for industrial pressure measurement applications.

● IP67 Protection
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Measurement & Testing Principle

Pressure Sensing

Utilizes a micromachined piezoresistive silicon sensor or ceramic capacitive cell. Media pressure deflects the isolating diaphragm, transferring oil fill fluid to the sensing element. This generates a proportional capacitive or millivolt bridge voltage, converted via 24-bit ADC.

Temperature Sensing

Employs a direct 4-wire Pt100 element inserted through an integrated thermowell or remote capillary. Resistance changes are measured via constant current excitation and calculated through mathematical polynomial algorithms.

Factory Calibration Testing

Every unit undergoes multi-point automated thermal compensation across -40 deg C to +85 deg C and 10-cycle pressure shock testing using calibrated reference standards.

Product Types & Configurations

Model PT-200 (Direct Mount Integrated)

Rigid thermowell extension combined with a compact dual-compartment transmitter housing. Ideal for standard pipelines.

Model PT-300 (Remote Capillary)

Armor-protected capillary separation for high-vibration compressor skids or extreme process temperatures up to 400 deg C.

Model PT-400 (Sanitary Clamp)

Electro-polished 316L wetted parts (Ra <= 0.4 um) with Tri-Clamp connections for pharmaceutical and food biotech lines.

Key Features

01.

Dual-Sensor Architecture

Independent ADC channels for pressure and temperature processing prevent mutual signal cross-talk.

02.

Turn-down Ratio

Up to 100:1 rangeability, minimizing inventory holding for multi-range spares.

03.

Transient Protection

Built-in dual gas discharge tubes and transient voltage suppressor diodes suppress 6kV lightning surges (conforming to IEEE C62.41 Category B).

04.

Local Display Interface

Rotatable OLED graphic display with optical touch buttons for on-site span adjustment without opening the enclosure cover.

Technical Specifications

Parameter Category	Specification Details
Pressure Measurement Range	-100 kPa to 60 MPa (Gauge, Absolute, and Differential)
Temperature Measurement Range	-200 deg C to +600 deg C (dependent on thermowell material and sensor type)
Reference Accuracy	+/- 0.075 percent of calibrated span (optional +/- 0.04 percent FS)
Long-Term Stability	+/- 0.1 percent of URL per 3 years
Output Signal & Protocol	4-20 mA DC with HART (RS485 Modbus RTU optional)
Power Supply	12.5-45 VDC (Intrinsically safe loop powered)
Enclosure Rating	IP67 / NEMA 4X (Die-cast low-copper aluminum with epoxy powder coating; 316 stainless steel optional)
Explosion Protection	Ex ia IIC T4-T6 Ga/Gb; Ex d IIC T6 Gb

Applications

Petrochemical Refineries

Crude distillation column overhead pressure and reflux temperature monitoring.
Oil & Gas Pipelines

Booster station line monitoring.
Power Generation

Superheated steam turbine inlet pressure and bearing oil temperature control loops.
Chemical Reactors

Exothermic batch reaction vessel monitoring requiring SIL safety instrumented systems.

Installation & Operating Considerations

Mounting Orientation

Mount vertical to horizontal pipelines using standard 2-inch pipe brackets. For steam service, install siphon loops to protect the sensor diaphragm from direct steam flash temperatures.

Zero Adjustment

Perform zero trim via local pushbuttons or communication terminals only after the process line is depressurized and vented to atmospheric pressure.

Grounding

Connect the dedicated housing grounding screw directly to the plant earth grounding grid using >= 4 mm^2 copper wire to maintain EMC compliance.

Manufacturing & Quality Control

CNC Machining

Housing bodies and process flanges machined on multi-axis CNC turning centers to maintain exact thread tolerances and O-ring groove finishes.

Laser Welding

Diaphragm seals welded using automated fiber laser systems under high-purity argon shielding to eliminate micro-fissures.

Pressure Stress Screening

100 percent burn-in testing under thermal cycling (-30 deg C to +70 deg C for 48 hours at 1.5x rated working pressure) prior to final electrical calibration.

Customization & OEM

OEM Branding

Laser-etched private labels, custom laser-marked stainless steel nameplates, and firmware ID string customization.

Process Connection Variants

Tailored thread standards (NPT, BSP, G, Metric), flange dimensions (ANSI, DIN, JIS), and special insertion lengths.

Material Certification

EN 10204 3.1 material test certificates provided for all wetted pressure-retaining components.

Selection Guide

Model Code	Sensor Type	Wetted Material	Max Process Temp	Explosion Proof	Primary Target Industry
PT-200-S	Piezoresistive + Pt100	316L Stainless Steel	150 deg C	Ex ia IIC T6	Water Treatment / General HVAC
PT-300-H	Capacitive + Thermocouple	Hastelloy C-276	400 deg C	Ex d IIC T6	Petrochemical Refineries
PT-400-F	Capacitive + Pt100	Tantalum Diaphragm	200 deg C	Ex ia IIC T4	Fine Chemicals & Acid Lines

Frequently Asked Questions

Q: How does the transmitter handle simultaneous measurement errors caused by high process temperatures affecting the pressure sensor body?

A: The internal firmware incorporates real-time digital temperature compensation algorithms. An embedded temperature sensor inside the electronics module continuously measures ambient and terminal block thermal gradients, applying dynamic correction matrices to neutralize temperature-induced zero and span shifts.

Q: Can the HART protocol communicate through existing barrier networks in brownfield plant upgrades?

A: Yes. The transmitter is fully backward compatible with standard HART communication protocols and operates transparently through standard galvanic isolators and zener barriers, provided the total loop resistance remains within the operating envelope defined by R_L = (V_supply - 12.5) / 0.022 ohms.

Q: What documentation is included for safety-instrumented systems (SIL) compliance?

A: Units ordered with SIL compliance options ship with FMEDA reports, relevant safety manuals, and third-party compliance documentation confirming Safe Failure Fraction and average probability of dangerous failure on demand (PFD_avg) ratings.

Q: How do we specify the correct capillary length for remote-mount transmitter configurations?

A: Specify the exact distance from the process tapping point to a safe, accessible mounting bracket (standard stock lengths: 3m, 5m, 8m). Avoid coiling excess capillary tightly; secure it rigidly with clamps every 0.5 meters to prevent movement-induced hydraulic pressure fluctuations.

Q: What are the lead times for standard stock configurations versus custom wetted material orders?

A: Standard models (316L wetted parts, 4-20mA/HART, standard NPT threads) ship within 3 to 5 business days for quantities under 10 units. Custom configurations involving exotic materials like Hastelloy, Monel, or specialized flange standards require 2 to 3 weeks for CNC machining and helium leak testing.

Q: What failure mechanisms are covered under the standard warranty terms?

A: The warranty covers material defects and manufacturing non-conformances, including electronic component failure, zero drift exceeding +/- 0.2 percent per year outside normal wear, and sensor oil-fill leakage under rated operating limits. Misapplication, physical damage from water hammer, or chemical attack beyond specified wetted limits are excluded.

Dalian Yheng Technology Co., Ltd. is one of the leading pressure & temperature transmitter manufacturers and suppliers in China, also supports customized service. We warmly welcome you to buy high quality pressure & temperature transmitter in stock here from our factory. Contact us for more details.

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