Original Yokogawa Eja438e Diaphragm Seal Type Differential Pressure Transmitter with Hart Protocol

• Customization: Available
• Type: Differential Pressure Transmitter
• Structure Type: Remote Diaphragm Seals
• Model NO.: EJA438E
• Measuring Medium: Liquid
• Accuracy Grade: ±0.2%
• Pressure range: -500-500kpa
• IP Rating: IP67
• Certification: CE
• Customized: Customized
• Item Name: Eja438e Diaphragm Seal Type Differential Pressure
• Model: Eja438e
• Type Name: Differential Pressure Transmitter
• MOQ: 1PC
• Warranty: 1 Year
• Accuracy of Span: 0.2 % of Span
• Temperature Limits: −40 to 60°c (−40 to 140°f)
• Pressure Limit: 2.7 Kpa ABS{20 Mmhg ABS}
• Supply Voltage: 10.5 to 42 V DC
• Housing: Low Copper Cast-Aluminum Alloy with Polyurethane
• Name Plate and Tag: JIS SUS304 or SUS316
• Integral Indicator: LCD Digital Indicator
• Output Signal: 4 to 20 Ma DC, 2-Wire System
• Mounting: Transmitter; 2-Inch Pipe Diaphragm Seals;Flange
• Power Supply Effect: ±0.005 %/V (21.6 to 32 V DC, 350 Ω)
• Transport Package: Carton Boxes
• Specification: 70/42/26cm
• Trademark: Yokogawa
• Origin: Japan
• HS Code: 9026900000
• Production Capacity: 100/Month
• Package Size: 71.00cm * 42.00cm * 26.00cm
• Package Gross Weight: 20.000kg

Product Description

Product Description

Yokogawa EJA438E Diaphragm Sealed Differential Pressure Transmitter: Comprehensive Technical Overview
1. Product Overview
The Yokogawa EJA438E is a high-performance diaphragm-sealed gauge pressure transmitter designed for demanding industrial applications. As part of the EJA-E series (launched in 2012), it integrates Yokogawa's DPharp digital sensor technology with robust remote-seal systems. This configuration isolates the sensor from direct process media contact, making it ideal for measuring corrosive, high-viscosity, crystallizing, or extreme-temperature fluids (e.g., chemicals, cryogenic liquids, or high-temperature steam). The transmitter outputs a standardized 4-20 mA DC signal with digital communication via BRAIN, HART, or other protocols, ensuring compatibility with modern control systems.

Detailed Photos

 

Product Parameters

Parameter	Specification
Measurement Range	0.06-3,500 kPa (8.5-500 bar)
Accuracy	±0.2% of span (standard)
Response Time	≤200 ms
Output Signal	4-20 mA DC (with BRAIN/HART/FF/PROFIBUS PA)
Power Supply	10.5-42 V DC (standard); 9-28 V DC (1-5V HART)
Operating Temperature	-40-85°C (process); -30-80°C (ambient)
Protection Rating	IP67 (standard)
Certifications	SIL 2/SIL 3 (TÜV/Exida), ATEX, IECEx
Fill Fluid Options	Silicone oil, Fluorocarbon, etc.

3. Core Technologies & Design Innovations
a) DPharp Digital Resonant Sensor
Utilizes single-crystal silicon resonators that vibrate under pressure-induced stress. Frequency changes are converted to precise pressure readings, providing twice the stability and accuracy of analog sensors.
Immune to signal drift caused by temperature fluctuations or mechanical wear, ensuring long-term reliability.
b) Remote Diaphragm Seal System
Constructed Materials: Diaphragms available in Hastelloy, 316L stainless steel, or tantalum; capillary tubes (max 15m) filled with temperature-stable fluids (e.g., silicone oil).
Active Capillary Compensation: Compensates for fill-fluid density changes due to ambient/process temperature variations, eliminating measurement drift in long capillary runs 
c) Advanced Diagnostics & Safety
Self-Diagnostic Suite: 40+ checks, including patented Back-Check Technology that verifies sensor integrity in real-time by confirming reverse calculations.
SIL 2/SIL 3 Compliance: Certified by TÜV and Exida for safety-critical applications (e.g., chemical plants, oil refineries) 
4. Functional Capabilities
a) Signal Processing & Customization
10-Segment Signal Characterizer: Linearizes non-linear processes (e.g., tank level strapping, flow measurement) via user-defined point-to-point compensation.
Local Parameter Setting (LPS): Adjust zero/suppression spans, damping, and units via the integral button-operated display without external devices.
b) Communication & Integration
Multi-Protocol Support:
BRAIN/HART: Enables remote configuration via Yokogawa's BT200 communicator or host systems.
FOUNDATION Fieldbus/PROFIBUS PA: Facilitates bidirectional data exchange in digital bus networks.
Integrated Digital Display: Shows process variables (PV), diagnostics, and a dynamic bar graph. Operates independently from the 4-20 mA circuit for localized monitoring 
c) Ruggedized Construction
Housing: Cast aluminum alloy (IP67) or stainless steel (optional).
Process Connections: 1/2 NPT or M20 cable glands with dual-conduit entries 
5. Target Applications

Industry	Use Case	Benefit
Oil & Gas	Separator vessel level/interface detection	Handles viscous crude oils without clogging
Chemical	Reactor pressure monitoring in corrosive processes (e.g., HCl synthesis)	Tantalum seals resist pitting corrosion
Pharma	Bioreactor sterilization (SIP) pressure control	Maintains accuracy at >150°C steam conditions
Power	Feedwater pump discharge pressure in thermal plants	SIL 3 certification for safety shutdown systems
Wastewater	Slurry tank level measurement	Diaphragm seals prevent media crystallization

6. Installation & Maintenance Guidelines
a) Mounting Best Practices
Seal Orientation: For horizontal pipes, mount with the high-pressure (HP) side on the left. Ensure capillaries are secured without sharp bends.
Impulse Piping: Use short, direct runs with a 1:10 slope to prevent gas/liquid accumulation. Isolator valves recommended for hot media (>200°C).
b) Wiring & Grounding
Load Limits: Max 1,290 Ω for 4-20 mA HART/BRAIN; ≥1 MΩ for 1-5V HART (3-wire).
Grounding: Mandatory 14 AWG wire to earth ground terminal to mitigate EMI/lightning risks 
c) Calibration & Diagnostics
Zero Adjustment: Perform after process stabilization using LPS or communicator.
Fill-Fluid Health: Monitor via sensor diagnostics; density shifts trigger alerts.
7. Compliance & Certifications
Functional Safety: IEC 61508 SIL 2/3 (TÜV Rheinland/Exida).
Explosive Atmospheres: ATEX, IECEx (Ex ia/ib IIC T6).
Environmental: RoHS 3, REACH 
8. Conclusion
The Yokogawa EJA438E sets the benchmark for diaphragm-sealed transmitters by merging laboratory-grade accuracy (±0.2%) with industrial durability. Its DPharp sensor, coupled with active thermal compensation and SIL 3 readiness, makes it indispensable for critical processes where safety, media compatibility, and long-term stability are non-negotiable. For installation manuals, protocol-specific configurations, or SIL documentation, consult Yokogawa's technical portal.

Company Profile

KeRui (weifang) Automation Equipment Co., Ltd. specializes in industrial automation instrument development, production and sales,technical services, and supporting equipment supply of specialized companies. The main products are flow meters, level meters,temperature meters, pressure meters, electrical meters, thermal intelligent meters, programmable controllers (PLC), DCS distributed control systems, and eight series of more than 1,000 specifications. Its products and technologies are widely used in electric power, metallurgy, petrochemicals, environmental protection, plastics, food, printing, tobacco, textile, dyeing, and other fields.
 

Packaging & Shipping

The packaging and transportation of instrumentation in global trade hinges on a synergy of advanced materials, rigorous testing, regulatory compliance, and smart logistics. By adopting hybrid structural designs, leveraging real-time monitoring technologies, and prioritizing sustainability, exporters can ensure the safe, efficient, and cost-effective delivery of precision instruments. Continuous innovation in materials science and IoT integration will further redefine industry standards, enhancing resilience in an increasingly interconnected market.

FAQ

Q: How long will you give me the reply?
A: We will reply to you as soon as we see the information.
Q: What is the delivery time?
A: Our delivery time is within 3-7 days after we get your payment;
for large qty mass orders, the time should be confirmed again for you.
Q: How about your package?
A: Do not worry about the package, we have rich experience in packing, and all our package is wooden case package.
Q: How about the payment terms?
A: You can choose T/T.
Q: Do you provide samples?
A: Yes, we have materials in stock to help you to get the samples as soon as we can.
Q: What is the MOQ?
A:1PC.
Q: Can I get a lower price if I order large quantities?
A: Yes, cheaper prices with more bigger size orders.