Hydac EDS 3400 Electronic Pressure Switch with Digital Display

Overview

The Hydac EDS 3400 is a compact electronic pressure switch for relative pressure measurement in the high-pressure range. A stainless steel measuring cell with a thin-film strain gauge converts system pressure into an electrical signal, and a built-in four-digit display shows the value locally so that a technician can read the pressure without connecting a separate gauge. The instrument offers one or two switching outputs and, in its extended versions, an additional switchable analog output, which lets a single device handle limit switching and continuous monitoring on the same measuring point.

Seven Star LLC supplies the Hydac EDS 3400 to hydraulic power units, pneumatic systems and refrigeration plants across the Sultanate of Oman and the wider GCC, with engineering support in Muscat. The Hydac EDS 3400 datasheet quoted on this page is the manufacturer document for the US catalog edition, which states ranges in psi, so buyers who need bar or MPa ranges can request a quotation against the metric part number and confirm the exact order code with our team before purchase.

Operating Principle

The pressure port of the Hydac EDS 3400 carries the medium directly onto a stainless steel diaphragm that carries a thin-film strain gauge. When pressure deflects the diaphragm, the resistance of the bridge changes in proportion to the applied pressure, and the on-board electronics condition and temperature-compensate the signal over a compensated range of 14 to 158 °F. The manufacturer states an accuracy of ≤ ±0.5 % of full scale (typical) according to DIN 16086, a repeatability of ≤ ±0.25 % and a long-term drift of ≤ ±0.3 % per year, figures that matter on machines which run for thousands of hours between calibrations.

The measured value in the Hydac EDS 3400 is compared with the programmed switching points in a microprocessor, and the result drives PNP transistor outputs that can carry up to 1.2 A each with a reaction time below 10 ms. Each output of the Hydac EDS 3400 can work as a switch-point function or as a window function, can be set to normally open or normally closed, and can be delayed on switch-on or switch-off between 0.00 and 99.99 seconds. A display filter smooths the readout under pressure pulsation, and the peak value of the pressure can be recalled on the display, which helps when commissioning pumps and accumulators that generate short pressure spikes.

Engineering Design of the Hydac EDS 3400

A distinctive feature of the Hydac EDS 3400 is that the display head can be moved in two planes. The Hydac EDS 3400 can therefore be installed in almost any position, and the display can still be turned toward the operator without a mechanical adapter, which saves fitting time on crowded manifolds and valve blocks. The process connection is a 9/16-18 UNF 2A (SAE 6 male) thread tightened to 15 lb-ft (20 Nm), the wetted parts are stainless steel with an FPM seal, and the electrical connection is an M12x1 male connector, 4-pole for outputs 1, 2 and 3 or 5-pole for the version with two switching outputs plus analog output.

The Hydac EDS 3400 housing is rated IP 67 according to IEC 60529, and the manufacturer specifies vibration resistance up to 10 g between 10 and 500 Hz and shock resistance up to 50 g for 11 ms. The unit has over-voltage, override and short-circuit protection, and a programming lock prevents accidental changes after commissioning. All settings are grouped in two short menus, so a technician can adjust switch points, hysteresis, delays and the unit of measurement (bar, psi or MPa) with the three keys on the front, and the instrument converts the switching settings automatically when the unit is changed.

Key Features

The Hydac EDS 3400 packs measurement, local indication and switching into one compact housing. Its main capabilities are listed below:

• Compact stainless steel measuring cell with thin-film strain gauge for relative pressure in four ranges from 1000 to 9000 psi.
• One or two PNP transistor switching outputs rated up to 1.2 A each, with a reaction time below 10 ms.
• Optional switchable analog output of 4 .. 20 mA or 0 .. 10 V for PLC supervision of the same measuring point.
• Four-digit LED display that can be rotated in two planes and shows pressure in bar, psi or MPa.
• Accuracy of ≤ ±0.5 % of full scale typical, with repeatability of ≤ ±0.25 % of full scale.
• Switch points, hysteresis, window function, switching direction and on/off delays adjustable from the front keys.
• Display of actual pressure, peak value or switch points, with a display filter for pulsating pressure.
• IP 67 housing with M12x1 connector and an optional DESINA-compliant pin configuration with diagnostic signal.

Industrial Applications

The Hydac EDS 3400 is aimed at hydraulics and pneumatics, and the manufacturer also lists refrigeration and air conditioning technology as a main field. In Oman the Hydac EDS 3400 therefore appears in hydraulic power units on drilling and workover equipment, press and lifting systems in fabrication yards at Sohar and Duqm, tank-farm valve actuation, and accumulator stations that need a pressure limit switch with local indication. The 1000 to 9000 psi ranges cover everything from lubrication and pilot circuits up to high-pressure test benches and accumulator charging circuits.

Because the Hydac EDS 3400 combines a switching output with an optional analog signal, maintenance teams in the GCC can wire it directly into a PLC input for supervision while the local display supports fault finding on site. Buyers who compare electronic switches can also review the WIKA PSM01 compact pressure switch or the United Electric One Series 1XSWLL pressure switch in our catalog, and mechanical differential applications are covered by the CCS 646DZE differential pressure switch. Seven Star LLC can help select the correct range, output option and connector for each circuit so that the overload and burst ratings of the chosen version stay well above the highest pressure peak in the system.

Technical Specifications

Key parameters of the Hydac EDS 3400 taken from the manufacturer datasheet (US catalog edition):

Request a Quote for Hydac EDS 3400

To request a quotation for the Hydac EDS 3400, check current availability and lead time or download the manufacturer datasheet from the document tab on this page, contact the instrumentation team at Seven Star LLC with your required pressure range, output version and connector. We supply the Hydac EDS 3400 to industrial and oil and gas customers in Oman and the GCC and can support selection, commissioning questions and repeat orders.

Other Hydac models from Seven Star LLC: Hydac ETS 1700 electronic temperature switch, Hydac RFM return line filter and Hydac SB330 bladder accumulator.