Absolute Transducers, Basic Rules, Forepeak Tank

Installation & User Manual

Ed 19UK	June 2013

Absolute Transducers:

The Absolute Transmitter is typically used if the amplifier is exposed to water, e.g. on open deck. The Absolute Transmitter is available in 2 ranges: 0-20 and 0-35 mH2O. In practice this means 10 mH2O less than the nominal range because of the atmospheric pressure which must be taken into consideration when choosing the transducer.

A transducer with an effective range larger than the tank height should be selected.

Basic Rules:

1.The selected measuring range must be larger than the tank height.

2.The selected measuring range must be larger than tank height + vent pipe height

EXAMPLE: Tank height	=	6 m
Vent pipe height =		14 m

1. The selected measuring range must be larger than 6 m due to the height of the tank.

2. The selected measuring range must be larger than	6 + 14	= 10 m due to the total height of the
	2

tank and the vent pipe combined.

Select a transducer with a measuring range of 16 mH2O as this is the next measuring range larger than 10 m.

Turn the range select switch on the amplifier to range No. 7.

Normally the selection of transducer, range select and calibration are done by DAMCOS.

Special consideration applies to e.g. forepeak tanks and draft measuring when selecting the measuring range of the transducer.

Forepeak Tank:

Transducer measuring range > tank height: Select the next measuring range.

EXAMPLE: Tank height 12 m.

Based on the tank height a transducer with a measuring range of 16 mH2O should be selected.

However, due to the dynamic conditions in the forepeak tank, a transducer with a measuring range of 35 mH2O, i.e. the next in line, should be selected.

Turn amplifier range select switch to range No. 6.

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