Oxygen Analyzer rear panel

The Oxygen analyzer pictured above is typical of the gas analysers offered. We produce analyzers for a variety of gases and other variables including……

Gas/variable Range Technology

Oxygen 0-25% fuel cell

Methane 0-2% pellistor

Carbon Dioxide various NDIR

Carbon Monoxide various NDIR/fuel cell

Hydrogen 0-200ppm fuel cell

Ammonia 0-200ppm fuel cell

Hydrogen Suphide Various to 1500ppm fuel cell

Chlorine 0-100ppm fuel cell

Nitric Oxide 0-5000ppm fuel cell

Temperature/pressure/humidity environmental various

Pressure&flow various piezo resistive

Moisture content 0-100% not telling!!

In addition, we produce a Metabolic Monitor for studies of small ruminent quadripeds. We can also produce semi-custom gas analyzers for unusal gases and gas concentrations.

Oxygen Analyzer description

The analyzer is a compact unit designed for laboratory use. The front panel offers sample inlet & outlet nipples, a flow indicator, an LCD display, and 4 touch-buttons.

The front panel is made of ‘Lexan’ polycarbonate for wipe-clean use. The various operations of the unit are displayed on the LCD and controlled using the push-buttons.

The rear panel has 20 turn screwdriver adjustable potentiometers to set zero and span for the target gas. It also has a DC power jack for the external mains adapter. This needs to be only +9VDC @ >300mA unregulated, with a standard 2.1mm power jack fitted. Two DIN sockets provide a means of connection to the analog output and the aux output. The analog output is intended for connection to an external measuring device such as a chart recorder or PC a/d converter. The aux output can switch a small reed relay or similar, to control/ enable an external device (it has various potential uses). A 9 pin female D-connector provides RS232 communications to an external computer. A simple command set enables the device to be fully controlled by programs written by the user or Coast Electronics.

The unit is ‘intelligent’. It contains a microcontroller IC which handles the display and response to the push-buttons. It sets pump rate and organises the RS232 i/o.

Routine maintenance

Contaminants should be prevented from entry to the sample system. Very humid samples should be dried using ‘drierite’ or other common dessicant. A particle filter may be used if thought necessary. In the case of extreme contamination, the case may be opened. slide the dark grey tabs on the top of the case outward (they have screwdriver twist-slots to assist this) to expose the case fixing screws. unscrew the 4 screws using a No.2 phillips driver. Lift off the case lid. If the sensor is type KE25 it simply unplugs from its cuvette. If the sensor is a CAG type it unscrews. Clean the sensor using a dry tissue. Sample tubing may be removed, cleaned and re-fitted. The pump should not need attention and should be replaced if faulty.

Operation

After switch-on the unit displays a sign-on message which identifies it. It then goes to a ‘normal’ operation mode. In this mode it displays the current gas reading. It also shows the highest (peak) and lowest (trough) long term reading. These values are reset by the ‘start’ button. The pump rate may be adjusted.

Hitting the right hand button changes mode. there is also (currently) a ‘show’ mode, which tells you the firmware revision and build version of the unit, a ‘setup’ mode which enables pump rate etc. to be set, and a ‘PC link’ mode which initiates communication by RS232 to an external computer. Other features may be added which should be self-explanatory.

SPECIFICATIONS

APPROX. SIZE: HEIGHT 70mm(2.75”)

WIDTH 292mm(11.5”)

DEPTH 210mm(8.25”)

RANGE: 0 TO 25% OXYGEN

RESOLUTION: 0.1%

LINEARITY: INTRINSICALLY LINEAR

POWER CONSUMPTION: APPROX. 2W MAX.

SUPPLY: +9VDC (MAINS ADAPTER)

SENSOR: FUEL CELL

RESPONSE TIME: <30 SECONDS

DISPLAY: 40x2 CHARACTER LCD

WEIGHT: APPROX. 1.7Kg

OPERATION: STANDARD LAB CONDITIONS

RS232 I/O: 8 BITS, 1 START,1 STOP, NO PARITY,9600 BAUD

ANALOG OUT: 0 TO +2.5VDC (2.5V=25%)

AUX OUT: SWITCHED +4.8VDC 100mW APPROX.l