Keller LEX1 (300bar) Digital Precision Manometer

  • Measures absolute pressure from 0 to 300bar with accuracy of ±0.05% FS
  • Digital self-calibration function with adjustable end point and zero point
  • Works as part of a Keller-Bus protocol monitoring system
More Info
inc VAT £780.00 ex VAT £650.00
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Product Details

Keller LEX1 Digital Precision Manometer (300bar)

The Keller LEX1 Digital Precision Manometer is an advanced industrial pressure gauge that can also be used for calibration and laboratory applications. It has an absolute pressure measurement range of 0 to 300bar, accuracy of ±0.05% FS and a resolution of 10mbar. A piezoresistive pressure transducer in the oil-filled casing and a G ¼” male connector are used to take readings.

The Keller LEX1 has a clear digital screen that displays readings in a number of different units. The pressure gauge boasts a zero function and a min/max display whilst digital calibration with a zero point and an end point helps ensure accuracy.

An RS485 Fischer connection means that the Keller LEX1 can work with up to 127 other instruments as part of a Keller-Bus protocol. Free Keller CCS30 software is available to download from the Keller website and can be used to coordinate a Keller-Bus protocol. A Keller K114A cable adaptor is needed to connect the RS485 connection to a USB port.

The Keller LEX1 is operated using just two buttons and has an IP65 ingress protection rating so it is ideal for use in difficult conditions. A 2000-hour battery life adds a further level of practicality.

Keller part number: 303030.0003

Key Features

  • Oil-surrounded piezoresistive transducer
  • Absolute pressure range: 0 to 300bar
  • Accuracy: ±0.05% FS
  • Resolution: 10mbar
  • G ¼” male connector
  • Laboratory, calibration, industrial
  • Several units of pressure
  • Digital calibration feature
  • Min/max and zero functions
  • Works in a Keller-Bus protocol
-1 to 3bar
-1 to 30bar
0 to 100bar
0 to 300bar
0 to 400bar
0 to 700bar
0 to 1000bar
Accuracy ±0.5% FS ±0.1% FS ±0.1% FS ±0.1% FS ±0.05% FS ±0.1% ±0.05% FS
(at smallest range)
10mbar 1mbar 1mbar 1mbar 1mbar 1mbar 0.1mbar
Temperature range 0˚C to 50˚C
Temperature accuracy ±1˚C
Intrinsically safe
Peak mode
Pressure connector 7/16" UNF G 1/4" 7/16" UNF G 1/4" G 1/4" G 1/4" G 1/4"
Analogue output
Internal memory
Data port RS485 Binder USB RS485 Fischer RS485 Fischer
Compatible with
Keller-Bus protocol
More Information


  • Absolute pressure range: 0 to 300bar
  • Overpressure: 600bar
  • Resolution: 10mbar
  • Accuracy @ RT (20˚C to 25˚C): ≤±0.05% FS. Nonlinearity (BFSL), pressure hysteresis, non-repeatability, zero point, amplification.
  • Total error band (0˚C to 50˚C): ≤±0.05% FS. Max. deviation within the specified pressure and temperature range.
  • Long-term stability: ±0.1% FS. > 1 bar, per year under reference conditions, yearly recalibration recommended.
  • Long-term stability: ±0.1mbar. ≤ 1 bar, per year under reference conditions, yearly recalibration recommended.
  • Degree of dependency on location: <±1.5mbar. Calibrated in vertical installation position with pressure connection facing downwards.
  • Accuracy of temperature measurement: ±1˚C typ.
  • Pressure range reserve: ±10%

Electrical Data

  • Battery: 3 V, type CR2430. LEX1 Ei only permitted for use in haz- ardous atmospheres when used with the Renata CR2430
  • Battery life: Approx. 2000 hours when used continuously
  • External power supply: 8...28 VDC
  • Overvoltage protection and reverse polarity of external power supply: ± 32 VDC
  • RS485 voltage insulation: -7...+12 VDC
  • GND case insulation: > 10 MΩ @ 50 VDC
  • External interface: RS485 half-duplex
  • Interface measuring rate: 30 measurements per second
  • Electrical connection: Fischer D 103 A054-130
  • CE conformity as per 2014/30/EU (EMC): EN 61000-6-1 to -6-4; EN 61326-1 / EN 61326-2-3

Temperature Range

  • Compensated temperature range: 0...50 °C
  • Media temperature: 0...50 °C
  • Ambient temperature: 0...50 °C
  • Storage temperature: -20...70 °C


  • Dimensions/appearance: See Dimensions & options
  • Number of digits on LC display: 2 rows with 5 digits each
  • Display mode: Pressure + min/max or pressure + temperature
  • Measuring rate: 2 measurements per second
  • Configurable units of pressure: [bar], [mbar], [hPa], [kPa], [MPa], [PSI], [mH2O], [cmH2O], [inH2O], [ftH2O], [mmHg], [inHg], [kp/cm2]
  • Additional units of pressure: 5 user-defined units can be configured

Mechanical data

  • Pressure connection: Stainless steel AISI 316L
  • Pressure transducer separating diaphragm: Stainless steel AISI 316L
  • Pressure transducer seal (internal): FKM (Viton® type A)
  • Pressure connection seal (external): FKM (Viton® type A)
  • Display housing: Faradex AS-1003
  • Oil filling sensor: Silicone oil
  • Pressure connection: G1/4, see Dimensions & options
  • Diameter x height x depth (approx.): 76 x 118 x 55 mm
  • Weight (approx.): 300 g
  • Protection: IP65
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pdf Keller LEX1 Datasheet pdf 1.7 MB Download