KELLER ECO2-Ei ATEX Digital Pressure Gauge

He KELLER ECO2-Ei ATEX digital pressure gauge It is a compact and economical instrument intrinsic safety, Designed to measure pressure in potentially explosive atmospheres. It is certified for use in Zone 0 with marked II 1G Ex ia IIC T5 Ga and has ATEX, IECEx and UKEX certifications.

The ECO2-Ei is available with ranges of 0…31 absolute bar and 0…300 bar. It offers an accuracy of ±0.5 % of the full scale at room temperature and a total error band of ±1.0 % FS between 0 and 50 °C. Its two-line LCD screen allows you to view the current pressure and the minimum or maximum value measured since the last reset.

ATEX digital pressure gauge for explosive atmospheres

The KELLER ECO2-Ei is designed for industrial applications where explosive gas atmospheres may form and pressure needs to be checked directly at the point of measurement. Its intrinsically safe design limits the electrical power available to the instrument to reduce the risk of ignition.

Dialing II 1G Ex ia IIC T5 Ga It allows it to be used as Category 1G equipment in Zone 0. It can also be used in Zone 1 and Zone 2, provided that the installation, grounding, temperature and maintenance conditions indicated by KELLER are respected.

The ECO2-Ei requires no external power supply or signal wiring. It is battery-operated and has no analog output, digital interface, or historical data logging. Its function is to provide a local pressure reading and store the minimum and maximum values since the last reset.

ATEX, IECEx and UKEX certification of the ECO2-Ei

The letter X The certificates indicate that special conditions for safe use must be observed. These include grounding the pressure connection, using only the authorized battery, and preventing electrostatic charges in the vicinity of the instrument.

Pressure ranges of 31 and 300 bar

The ECO2-Ei intrinsically safe digital pressure gauge is offered in two configurations:

• ECO2-Ei of 31 bar: range of 0…31 bar absolute, resolution of 0.01 bar and overload resistance of 60 bar.
• ECO2-Ei of 300 bar: range of 0…300 bar, resolution of 0.1 bar and overload resistance of 400 bar.

In the 31 bar version, the factory zero point is set to 0 bar absolute, i.e., a vacuum. The function can be applied to use the instrument as a gauge. ZERO SET when the sensor is exposed to atmospheric pressure.

In the 300 bar version, the zero point is set using atmospheric pressure as a reference. The model selection should be made considering the normal operating pressure, potential pressure spikes, and the required resolution.

Accuracy and total error band

The accuracy of the KELLER ECO2-Ei between 20 and 25 °C is ≤ ±0.5 % FS. This specification includes BFSL nonlinearity, pressure hysteresis, lack of repeatability, and zero-point and amplification deviations.

Within the compensated range of 0 to 50 °C, the total error band is ≤ ±1.0 % FS. This band expresses the maximum deviation within the specified pressure and temperature ranges and is the most representative data for estimating the maximum error during operation.

Long-term stability is ≤ ±0.2 % FS per year under reference conditions. For applications subject to quality procedures or metrological traceability, annual recalibration is recommended.

Display with minimum and maximum values

The LCD screen consists of two rows of 4.5 digits and takes two measurements per second. The top row displays the current pressure, and the bottom row typically shows the highest value recorded since the last reset.

Pressing the ENTER button briefly displays the minimum stored value for five seconds. The RESET function resets the minimum and maximum values to the current pressure, allowing a new check to be initiated.

When the value cannot be displayed, the screen indicates OFL for upper overflow or UFL for lower overflow. If the measurement range is exceeded, the last valid value flashes as an overload warning.

Functions of the KELLER ECO2-Ei pressure gauge

• MIN/MAX: query of the minimum and maximum measured values.
• RESET: reset of minimum and maximum values.
• ZERO SET: establishment of a new zero reference.
• ZERO RESET: factory zero reset recovery.
• OFF: manual shutdown.
• CONT ON: continuous operation without automatic shut-off.
• CONT OFF: Automatic shut-off after approximately 15 minutes.
• BAT LOW: low battery warning.

Configurable pressure units

The units are selected using the front buttons, without any additional software or equipment:

• bar
• amber
• hPa
• kPa
• MPa
• PSI
• kp/cm²

The unit and selected settings remain stored after the instrument is turned off.

G1/4 Swivel Adapter

The ECO2-Ei incorporates a male connection 7/16-20 UNF and is supplied with a swivel-type orientable adapter with process connection G1/4 male.

The Swivel system uses O-rings and allows the pressure gauge to be rotated to orient the display in the most comfortable reading position. The adapter can be tightened with a maximum torque of 50 Nm.

There are also optional adapters G1/8, 1/4-18 NPT and G1/4 according to EN 837 without swivel function.

Battery approved for ATEX zones

The pressure gauge is powered by a lithium battery. Renata CR2430 3V, included in the supply. Its autonomy reaches approximately 1,000 hours of continuous operation.

In potentially explosive atmospheres, only the Renata CR2430 battery specified by Keller is authorized for use. According to the manual, this battery can be replaced within the hazardous area, provided the manufacturer's instructions are strictly followed.

Special conditions for safe use

• The installation must be carried out by qualified personnel.
• The pressure gauge should only be installed with the system depressurized.
• The ECO2-Ei pressure connection must be grounded.
• In Zone Ex, only a Renata CR2430 battery should be used.
• Processes that generate electrostatically charged particles should not be carried out near the instrument.
• The temperatures and conditions indicated in the ATEX documentation must be respected.
• For special media or conditions, the compatibility of the materials must be checked beforehand.

The ambient temperature allowed by the Ex certification, from −10 to +80 °C, should not be confused with the metrological compensated range, which is from 0 to 50 °C, nor with the standard temperature of the medium indicated in the technical data sheet.

Materials and IP65 protection

The pressure connection and the separator membrane are made of AISI 316L stainless steel. The Swivel insert is made of nickel-plated brass, the gaskets are made of NBR, and the adapter is made of galvanized steel.

The screen housing is made of polyamide and the instrument offers a degree of protection IP65. For particularly demanding environments, a protective rubber cover can be added.

Applications of the ATEX digital pressure gauge

The KELLER ECO2-Ei is indicated for local pressure measurements in:

• Industrial facilities with potentially explosive atmospheres.
• Process zones classified as Zone 0, Zone 1 or Zone 2.
• Maintenance operations in chemical and petrochemical facilities.
• Process equipment, piping, tanks and pressurized circuits.
• Gas installations and other processes with potential presence of flammable gases.
• Checks that require a local digital reading without an external power supply.
• Monitoring of minimum and maximum values during pressure tests.

The final suitability of the pressure gauge for a specific fluid, zone, or process must be verified by considering the gas group, zone classification, temperature, pressure, and chemical compatibility of the materials.

References for the KELLER ECO2-Ei

Scope of delivery and accessories

• KELLER ECO2-Ei ATEX digital pressure gauge.
• Renata CR2430 battery installed.
• Swivel G1/4 male adjustable adapter.
• Copper gasket for G1/4 connection.
• Instruction manual.

Optional supplies include a protective rubber cover, a carrying bag, and KELLER calibration certificates with 5 or 11 measurement points.

Selection and supply of the ECO2-Ei

GUEMISA supplies the KELLER ECO2-Ei ATEX digital pressure gauge Available in 31 and 300 bar versions. To select the correct equipment, it is necessary to specify the maximum working pressure, the fluid, the required connection, the zone classification, and the temperature conditions.

For industrial applications without intrinsic safety requirements, please refer to the

KELLER ECO2 standard digital pressure gauge
.