NETcourse
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Alterations/Errors reserved 15/Wo/251D
Cassens & Plath GmbH, Am Lunedeich 131, D-27572 Bremerhaven, Germany, tel. +49 471 483 999 0, fax +49 471 483 999 10
www.cassens-plath.de
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4) Installation
4.1) Installation of Detector
This chapter may be passed in case the detector is already installed to the compass when
delivered.
As heading source a conventional compass has to be used. Installation of detector is
usually done by glueing it from below centric to the lower cover glass. Between detector
and lower cover glass of the compass a certain distance has to be kept. This will be
guaranteed by a special mounting cylinder which may be ordered from Cassens & Plath as
an extra. The height of the cylinder to keep the right distance between detector and
compass is calculated so that on the one hand any influence from the detector to the
compass indication can be excluded and on the other hand the magnetic field of the
compass card assembly is strong enough to drive the detector.
Attention:
If the detector is too close to the compass the directional system will be deflected!
If the detector is too far away from the compass the magnetic field strength will be
too low to drive the detector!
Keep the correct distance otherwise safe navigation will be not possible!
If the correct distance is unknown there are two different ways do determine it:
1. The magnetic moment (the strength of the magnets) of the compass is known. This
value will often be found in the compass certificate. If, for example, the value is
between 2.0 .... 4.5 Am
2
, the correct distance between detector and magnet of card
assembly is 110 mm. If the exact location of the magnets inside the float of the
directional system below the card level is unknown take 15 mm for this.
2. Mounting will be done by a qualified compass workshop owning a regular compass
test bench. The procedure to find the correct distance is the same as finding weak
iron interference by swirl error examinations. The compass is turned in a 4 min 360°
turn with and without detector. If there is any quadrantal weak iron influence visible
with the detector fitted the distance has to be increased. The best distance is the
one where just no longer any influence is visible; add 5 mm to this.
Detector mounted from above
This may be necessary in case the compass is an overhead compass, for example, or
there is already another detector from below. To find the correct distance between detector
and top cover glass, proceed same as above. It is necessary to interchange the green and
grey wire in the junction box.
Adjustment of Detector Alignment
Turn the detector so that the arrow shows in ahead direction of the compass. Now
continue with chapter 2.2) Menu Item “Transmission Error“ and follow the mentioned
procedure.
