The O2Cap family integrates an Oxigraf oxygen sensor with a NDIR CO2 sensor for dual gas measurements for research, industrial and laboratory measurements. Measure Oxygen concentrations from 5-100% and CO2 from 0-10%. Perform capnography tests with fast breath by breath measurement. The units come with a pump for gas sampling system, bright vacuum fluorescent alphanumeric display (VFD), touch panel keypad, a rear 0-1VDC analog output for O2 readings, and either a rear terminal strip with limit detection relays and 4 – 20 mA analog outputs or a second CO2 analog output, and a RS232 digital interface.

The model O2Cap and O2CapB have luer type front panel gas sample input fitting for research applications. The model O2CapD have CPC O-Ring quick connect gas sample fittings for industrial applications.

All of the Model O2Cap, O2CapB and O2CapD include a sampling pump that will draw a sample from atmospheric pressure; with an external flow control valve, it will accommodate pressurized gas up to 1.3 psig (17 psia or 120 kPa).

An optional gas sampling valve allows the pump to draw a sample for a programmable number of seconds. This feature is useful for sampling from Modified Air Packaging (MAP). Please contact Oxigraf for more information on this option.

O2Cap comes with LEUR fitting and gas sampling pump. P/N 07-0193

O2CapB replaces the Terminal Strip with a second BNC analog output for CO2 on the regular O2Cap. P/N 07-0387

O2CapD comes with CPC O-ring fitting and gas sampling pump. P/N 07-0358

O2Cap(AL) comes with CPC O-ring fitting and gas sampling pump to handle lower pressure inputs. P/N 07-7035

O2Cap(ALR) comes with Swagelok Fittings (1/8") for Gas Inlet and Outlet Ports and gas sampling pump to handle lower pressure inputs. P/N 07-7036

Unit of Measure

Performance Specifications


N/A 5 to 100% Oxygen, 0 to 10% CO2.


N/A 0.1% in 5 to 100% range (O2), 0.01% in 0 to 10% ranges (CO2)

Sample Flow

N/A 50-250 ml/min with sampling pump on, 50-500ml/min with pump off.

Response Time

N/A 150ms at 150 ml/min, filter setting 0 to 3.


Stability (4 hrs)

N/A ±0.1% CO2 after 5 minute warm up ±0.1% in Oxygen LN mode ±0.3% in Oxygen XC mode

Mechanical Specifications

Dimensions (W x H x D)

N/A 7.5x3.0x11.0 in190x76x280 mm

Weight Instrument

N/A 5 Pound2.3 Kilogram

Weight Power Module

N/A 1.5 Pound0.7 Kilogram

Performance Conditions

Ambient Temperature (Operating)

N/A 5 to 40 ºC40 to 102 ºF

Ambient Temperature (Storage)

N/A -20 to 60 ºC-2 to 140 ºF
Cell Pressure1 N/A 2.2 to 17.4 psi15 to 120 kPascal150 to 1200 mmHg

Warm-up for Full Accuracy

N/A 5 min


N/A Two point calibration required after change in altitude of 2000 feet

Room Humidity

N/A 0 to 95%, non-condensing

Electrical Specifications

Sensor Power Requirements

N/A 1.5 A 12VDC

External Power Supply

N/A 47 to 63 Hz 95 to 250 VAC

Features & Applications


  • Internal Sampling Pump.
  • Relay contacts can be used to control external equipment.
  • Relay contacts are Form C (SPDT), 5 A 250 VAC rating.
  • Analog 4 to 20 mA, analog 0 to 1 VDC, and digital RS-232 outputs. <li
  • Visual, audible, and remote alarms for Low O2, High O2, Low Flow and System Check.
  • Samples and displays oxygen from 5 to 100% without range switching.
  • Calibrates electronically using 10%O2/5% CO2 and 100% O2 cal gases.
  • Electronic flow meter and display included.
  • Front panel CPC-Quick connect fitting.
  • Fast Response (< 1 sec) for prompt analysis.
  • Pressure and temperature correction automatically.
  • No false oxygen readings with Ar, H2O, CO2, CO, or hydrocarbons.
  • Rugged laser diode absorption spectroscopy oxygen analysis.
  • Measures at low flows of 50 to 250 ml/min, conserving product gas.

  • 1 Limited by internal pressure regulator