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"Oil-Less” Medical Air Medical Systems

Appendix C - Ceramic Dew Point Monitor

C.1 Introduction

WARNING:

Before starting any installation, maintenance or service procedures, disconnect ALL
power to the system to prevent electrical shock hazard.

Before making or breaking any medical gas line connections, make sure the system is
depressurized in order to avoid personal injury.

Before removing the dew point sensor, verify that the source of line pressure has been
valved off or reduced to atmospheric pressure.

An alarm condition on the dew point display indicates a dew point level exceeding the
maximum set point, or a faulty dewpoint sensor. Immediate action should be taken to
reduce the possibility of high dew point in the Medical Air line.

If the dew point sensor orifice becomes clogged, dew point readings may be inaccurate,
allowing moisture to accumulate undetected.

The ceramic dew point hydrometer is a continuous, on-line instrument for the measurement of absolute
moisture content in gas. The instrument consists of two component parts: monitor and sensor, each of which
is calibrated to a single standard allowing combinations of sensor and monitor units to be totally
interchangeable.

The ceramic sensor is manufactured from metalized ceramics using thin and thick film technologies to produce
a sensor that is virtually chemically inert with inherently fast response, high calibration stability and high
resilience to corrosive environments. The ceramic hygrometer measures moisture by monitoring the electrical
response exhibited by the sensor to variations in the partial pressure of water vapor of the monitored gas.

C-1