Teledyne 311-D instruction manual Maintenance

If, on the other hand, the instrument is not to be used immediately after calibration, and a low ppm oxygen gas is being employed as a purge, allow the manifold to be purged overnight, and then disconnect both male fittings. ALWAYS DISCONNECT THE SOURCE FITTING FIRST, AND IMMEDIATELY THEREAFTER, THE VENT FITTING.

3.3Positive Pressure Sampling:When connecting the instrument to a positive pressure sample source, ALWAYS proceed as follows:

1.Before making ANY connections to the instrument, establish a sample line flow rate of 0.1 to 10 liters/min. Allow the sample to vent to atmosphere long enough to purge the line free of air.

2.Install the vent fitting first and then the sample source fitting. Be prepared to make the connections in rapid order, so that atmospheric diffusion time Through the vent fitting is held to a minimum.

When disconnecting the instrument, reverse the procedure: source fitting first, and then vent fitting.

The objective of the connect-disconnect procedure is to obviate the possibility of pressurizing the manifold. IF A FLOWING SAMPLE WAS CONNECTED TO THE MANIFOLD

WITHOUT THE VENT FITTING IN PLACE, THE PRESSURE IN THE MANIFOLD WOULD RISE AND BE EQUAL TO THE SAMPLE PRESSURE ALMOST IMMEDIATELY. In such a situation, depending on the magnitude of the sample pressure, leaks in the manifold might result.

3.4Atmospheric Pressure Sampling: If the sample is at atmospheric pressure (or slightly negative), a sample pump will be required downstream from the analyzer. The inlet side of the pump should also be equipped with a throttle valve, so that sample flow can be reduced to

0.1- 10 liters/min. If pump loading is a consideration, the inlet side of the pump will have to include a bypass path that is open to the atmosphere through still another throttle valve. The sample path and bypass path may then be balanced by manipulating the two valves, so that sample flow is within the prescribed limits without loading the pump.

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UNDER NO CIRCUMSTANCES SHOULD THERE BY ANY RESTRICTIONS IN THE LINE BETWEEN THE SAMPLE POINT AND THE ANALYZER --partial-pressure- sensitive device, any oxygen readings taken under these conditions would be erroneous, and vacuums in excess of 1/3 atmosphere may damage the cell.

4.MAINTENANCE

4.1Battery Power Supply Service. The Model 311D is for use ONLY when it is not connected to the AC power line. TAI suggests that an overnight recharge be accomplished