Schneider Electric EPP301 EP Differential Pressure Transmitter

EPP301: EP series differential pressure transducer for air, 250 Pa top range

The EPP301 is a Schneider Electric EP series differential air-pressure transmitter. The datasheet lists four selectable ranges up to 250 Pa, an accuracy of ±1 % of full scale, voltage and current outputs and an IP65 housing with a 6 mm brass fitting. It covers the lowest ranges of the group, from 25 Pa up to 250 Pa full scale.

Seven Star LLC supplies the EPP301 as an independent supplier in Oman and the GCC for HVAC and building-automation work. The product title in the datasheet mentions a different set of ranges (100, 300, 500 and 1000 Pa) than the specification table lists, so confirm the exact range set when you order.

Selection checklist for the EPP301

• Range: pick the working differential in the lower middle of the 250 Pa family range.
• Output: 0–5 V DC, 0–10 V DC or 4–20 mA to match the controller.
• Mounting: panel as listed.
• Display: no display size listed; choose an LCD-suffixed reference if one is wanted.
• Tubing: 6 mm fittings and suitable tube material.
• Calibration: the datasheet lists no calibration certificate.

Typical uses in Oman and the GCC

The datasheet lists duct pressure, filter, fan and VAV control and air velocity monitoring as applications. In the Gulf, filter monitoring is the one most often met, because sand and dust load pre-filters quickly during shamal and the alarm has to be reliable. Fan proving and VAV box control follow, in hospitals, towers and schools.

Keep the tubing out of direct sun, as heat softens plastic and changes its length, and shield the sensor from vibration where it is mounted on a fan casing.

How the EPP301 measures differential pressure

A differential pressure transmitter compares the pressure at two ports and reports the difference as an electrical signal. In an air system the two ports usually sit before and after a filter or coil, across a fan, or on the total and static taps of a velocity probe. The EPP301 outputs the result as 0–5 V DC, 0–10 V DC or 4–20 mA, so it can feed almost any controller input.

The datasheet describes the controlled fluid as air or gas and gives a burst pressure of 5 psid (34.5 kPa), which is a protection limit, not an operating range. Keep the process well below it, and avoid sudden pressure surges on the tubing when a fan starts or a damper slams.

Installation and commissioning

Mount the transmitter, connect the tubing to the correct ports and check polarity. Set the output type and range as described in the installation sheet, apply a known pressure with a handheld calibrator if available, and compare the signal. Because no calibration certificate is supplied, a field check is the only evidence of calibration.

Keep spares of this unit on site where filter alarms or fan proving depend on it. Check the tubing every year for kinks, loose joints and dust, because blocked tubing is the most common cause of a frozen reading.

Technical specifications of the EPP301

Choosing the range on the EPP301

The four ranges on the datasheet are 0…25 Pa, 0…50 Pa, 0…100 Pa, 0…250 Pa. A range should be picked so that the normal working differential sits between about a third and two thirds of the full scale, which leaves room to see a clogged filter or a fan trip without clipping the signal.

For clean-room, laboratory and low-velocity duct work, the lower ranges give the finest resolution. Accuracy is listed as ±1 % FS and drift as less than 2 %, so a 2 % drift on a 25 Pa range is a noticeable fraction of the signal; read the datasheet figure against your control tolerance.

Outputs, supply and wiring of the EPP301

Supply is 12–30 V DC or 24 V AC. The output type is selectable between 0–5 V DC, 0–10 V DC and 4–20 mA, and an RGB LED gives local status indication. No display size is listed for this version; the LCD-suffixed references in the same family list a 17 × 28 mm display, which is the choice when a local reading is wanted.

Wire with shielded cable on any run near variable-speed drives, and keep the current-loop option for long cable runs. The datasheet lists the connection as 22 AWG; confirm the lead construction when you order if you need a terminal-block version.

Information to send with an RFQ for the EPP301

• Exact reference EPP301 and quantity.
• Required range and tolerance.
• Output type and supply voltage of the controller.
• Mounting style and whether a display is wanted.
• Delivery location and project schedule.

Documents and quotation

The manufacturer datasheet for the EPP301 is attached on this page and carries the specification summarised above. Check the revision date printed on it against your project documents before you rely on a figure.

Send us the reference EPP301, the quantity and the delivery location, and Seven Star LLC will reply to your request. We are an independent supplier based in Muscat and we confirm availability and lead time per enquiry.