Greisinger GOEL 370, GOEL 380 User guide

Z11.0.1X.6C-15 page 1 of 4

WEEE-Reg.-Nr. DE93889386

GHM Messtechnik GmbH • Standort Greisinger

Hans-Sachs-Str. 26 • D-93128 Regenstauf

 +49 (0) 9402 / 9383-0  +49 (0) 9402 / 9383-33  [e-mail]

Operating Manual

GOEL 370, GOEL 380

Atmospheric Oxygen Sensor - Replacement

General information:

GOEL 370 (acidic electrolyte): Specialized sensor for diving application e.g. measuring Nitrox. Construction is

optimized to this application, especially during professional usage in harsh environment the higher price will pay.
Also suitable to measure oxygen-concentration in air or other gases with a high CO2-content or even in a CO2­atmosphere. The acid electrolyte guarantees that the sensor could not be influenced by CO2.

GOEL 380 (basic electrolyte): Sensor for low oxygen concentration e.g. controlled atmosphere. Without larger
CO2 concentration *).

*) The GOEL 380 (and formerly the GOEL 369) is designed to measure oxygen-concentration in air or other gases

without larger CO2 concentration. Higher CO2-concentration reduces the life-time of the sensor.
Short-time exposition of up to 10% CO2 is not problematic (for example 15 minutes. up to 10 times per day) for

the GOEL 380 (e.g. exhaust measuring). If there is measured more often with elevated CO2-concentration or at
CO2-concentrations above 10%, the exposition time has to be kept as short as possible and sufficient measuring
breaks should be made.

Note: If the sensor is not exposed to free air during measuring pauses, the connected tubes etc. have to be

flushed with clean air or nitrogen.

Z11.0.1X.6C-15 page 2 of 4

General information about the oxygen sensors

I.) Lifetime: At the end of life time the sensor signal drops relatively fast.

The electrode evaluation in % therefore just can be used for orientation. An evaluation of 70%
does not mean that 70% of life time are remaining, but 70% of the reference signal are available,
which happens normally at the end of life time.

Note: The electrode evaluation is updated by the instrument every time, when the calibration of the sensor was

performed successfully. (please also see the referring manual of the instrument)

The nominal life time can be shortened significantly by usage. Influencing factors are:

- Storage- / Operation temperature

- Humidity of measured gas: If permanently used with dry gases (technical gases, bottled gas) the life time
decreases considerably.
It helps, if the sensor is brought to normal humid ambient air in measuring breaks (“flush” system with fresh air).

II.) Operating position: The optimum operation position is with the sensor inlet pointing downwards,

maximum differential pressure to ambient is 250 mbar.

III.) Measuring precision: The measuring precision can be influenced by:

- Liquids at the sensor inlet. Rinse the inlet and dry with lint-free cloth.
Attention: avoid liquids of any kind at the contacts

- Gas and sensor temperature have to be at same level. Best precision, when calibrated at measuring
temperature.

- Pressure fluctuations: The sensor is originally a partial pressure sensor, i.e. changes in the absolute pressure
are influencing the measuring result directly proportional. A pressure change of 1% will cause a additional
measuring error of 1%!
For optimum precision calibrate at the same conditions at which You want to measure.

Safety requirements:

This device has been designed and tested in accordance with the safety regulations for electronic devices.
However, its trouble-free operation and reliability cannot be guaranteed unless the standard safety measures and
special safety advises given in this manual will be adhered to when using the device.

1. Trouble-free operation and reliability of the device can only be guaranteed if the device is not subjected to any
other climatic conditions than those stated under "Specification".

2. If the device is transported from a cold to a warm environment condensation may result in a failure of the
device. In such a case make sure the device temperature has adjusted to the ambient temperature before
trying a new start-up.

3. If there is a risk whatsoever involved in running it, the unit has to be switched off immediately and to be
marked accordingly to avoid re-starting.

Operator safety may be at risk if:

- there is visible damage to the device.

- the device is not working as specified.

- the device has been stored under unsuitable conditions for a longer time.
In case of doubt, please return device to manufacturer for repair or maintenance.

4. Warning: do not use these product as safety or emergency stop devices, or in any other application where
failure of the product could result in personal injury.
Failure to comply with these instructions could result in death or serious injury

5. Caution, acid! The sensor contains KOH (G___ 380) or acid (G___ 370).

KOH and acid can cause severe chemical burns!
If leaking, avoid contact!

If there was contact:

• to skin: Flush contacted area with large amounts of water for several minutes.

• to clothing: remove contaminated clothing.

• to eyes: Flush with large amounts of water for several minutes,
obtain medical treatment.

After swallowing:

• give large volumes of water. DO NOT induce vomiting!

• Obtain medical treatment.