HBM FS42, Руководство пользователя, Страница: 39 / 76

Measuring Examples
FS42
A4250-5.0 HBM: public
39
5.4 Common Measuring Difficulties
There may be the possibility of having measuring mal­
functions due to several problems in the sensing network
or optical connections. A list of some of the usual prob­
lems is described below with the explanation for its
occurrence and correction.
5.4.1 Dirty Connector
When an interrogator is repeatedly being plugged in and
out with optical connectors, it is very important that the
connectors are cleaned prior to any connection. Other­
wise, dust and moister can be deposited in the interroga­
tor adaptor and this will compromise measurements. In
Fig. 5.6 a picture of a magnified connector is presented.
The dark gray circle corresponds to the fiber cladding
and the small light gray circle is the core of the fiber. One
picture for a clean connector and one picture for a dirty
connector are presented.
Clean connector Dirty connector
Fig. 5.6
The most common effect of dirt on the connections is a
large amount of broad band light being reflected at the
connection, in both directions, meaning that the dynamic
range for measurements becomes smaller.