Product Overview

The Yokogawa EJA120A is a high-performance draft range differential pressure transmitter designed for ultra-low pressure measurement in industrial applications such as furnace draft control, cleanrooms, and gas flow monitoring. It utilizes Yokogawa’s proprietary DPharp digital silicon resonant sensor, which delivers high accuracy, long-term stability, and resistance to drift compared to conventional analog sensing technologies. Engineered for demanding environments, the EJA120A ensures precise and reliable pressure measurement from 0.1 to 1 kPa. We supply this unit as 100% brand new, original factory equipment to guarantee optimal performance and long service life.

Part Number Breakdown

• EJA120A: Draft range differential pressure transmitter

• -D: Output signal (4–20 mA DC with BRAIN or HART communication)

• -E: Measurement span (0.1 to 1 kPa draft range)

• -S: Wetted parts material (SST316, Hastelloy C-276)

• -2: Process connection (1/4 NPT female)

• -9: Electrical connection (1/2 NPT female)

Technical Specifications

Engineering Advantages

Ultra-Low Pressure Sensitivity
The EJA120A is capable of detecting extremely small pressure variations down to 0.1 kPa, making it ideal for precise control of combustion air, ventilation systems, and draft pressure regulation.

Superior Overpressure Protection
The robust DPharp sensor design withstands high static pressures and transient surges, reducing the risk of sensor damage during process upsets or improper valve operations.

Advanced RFI/EMI Immunity
Shielded electronics and housing design protect the transmitter from electromagnetic interference generated by nearby motors, drives, and communication equipment, ensuring stable signal output.

Simplified Field Calibration
Zero and span adjustments can be performed via external adjustment screws or handheld communicators using HART/BRAIN protocols, minimizing the need to open the housing in harsh environments.

FAQs

Does the EJA120A support remote diaphragm seals?
No, it is primarily designed for direct gas and draft pressure measurement. For corrosive or high-temperature liquid applications, models like the EJA118W with remote seals are more suitable.

Can the transmitter be installed in any orientation?
Yes, but orientation may affect the zero point due to fill fluid head. A zero calibration is recommended after installation to ensure accuracy.

How does the DPharp sensor differ from capacitance sensors?
The DPharp sensor uses a resonating silicon element that produces a frequency output, offering better long-term stability, reduced drift, and improved temperature resistance compared to capacitance-based sensors.

What is the G3 conformal coating option?
The G3 coating provides enhanced protection against corrosive gases such as hydrogen sulfide, extending the life of internal electronics in harsh chemical or wastewater environments.