3 Operation

Model OT-2 System

 

 

 

 

 

 

 

 

 

3.2Installing the Micro-Fuel Cell

The Micro-Fuel Cell is not installed in the cell block when the instrument is shipped. Install it before the analyzer is placed in service.

When the micro-Fuel Cell needs to be installed or replaced, follow the procedures in chapter 5, Maintenance, for removing and installing cells.

Recommendation: During installation, minimize the time the sensor is exposed to atmospheric oxygen, i.e. the time between removal of the sensor from the sealed bag to installation into the cell holder.

3.3Calibration

The calibration process consists of:

Connecting span gas to Span In Port

Setting the span

Setting the span of the transmitter requires adjustment of the potentiometer located on the transmitter box.

The sensor will respond to changes in oxygen concentration immediately after installation. For maximum performance (accu- racy and sensitivity) TET/AI recommends that the sensor be purged with a zero (0% oxygen) gas for about 24 hours after the sensor is installed and then calibrate with span gas with a value of approx. 80-100% of the analytical range of interest. The following sections describe the calibration procedure.

3.3.1Calibration Gas Connections

Prior to installation of the O2 cell, a zero gas (purge gas) con- taining less than 1 ppm O2, should be connected to the system and be ready to purge the O2 cell. To facilitate spanning the zero and span gas source can be connected to a common manifold via a three way valve. This manifold then connects directly to the "Span Gas In" port on the system (Fig. 3-5). It is important that the operator bleeds any trapped air in the tubing prior to installation of the sensor to minimize the amount of atmospheric oxygen introduced into the system.

NOTE: In order to minimize the time required to purge the cell after exposure to air, limit the time the cell is exposed to air to 1 minute or less, if possible.

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Teledyne Analytical Instruments

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Image 24
Teledyne operating instructions Operation Model OT-2 System Installing the Micro-Fuel Cell, Calibration