System and device for detecting the forming of depot

DETAILED DESCRIPTION I claim: 1.
System for detecting the forming of depot inside a transport channel for transporting particles in a light transparent carrier fluid, comprising a light transmitter, a light receiver, a bifurcated glass fibre cable of which the joint end is installed within the wall of a transport channel, one branch of the cable fork being coupled to the light transmitter and the other branch being coupled to the light receiver, and the output of said light receiver being connected to a discriminator circuit comprising a convertor for converting the effective ac voltage component in said received signal into a dc voltage component and a comparator in which said dc voltage signal is compared with a predetermined threshold signal.
2.
System according to claim 1, in which the output of the discriminator circuit is coupled to a visual indicator unit.
3.
System according to claim 1, in which the output of the discriminator circuit is connected to a transmitter for transmitting the output signal of the discriminator circuit to a corresponding receiver of which the output is coupled to said indicator unit.
4.
System according to claims 1, in which the discriminator circuit comprises an input on which a signal can be supplied in case the fluid does not contain any particles.
5.
System according to claim 1, in which the conduit section of the transport channel in which said joint end of the bifurcated glass fibre cable is installed has a somewhat larger diameter than the remaining sections of the transport channel.
6.
System according to claim 1, in which the joint end of the glass fibre cable is positioned within the lower part of the transport channel defined by an angle of .
+-.
30.
degree.
with reference to the vertical direction through the center point of the channel.
7.
Measuring system for detecting and measuring the forming of depot inside a transport channel for transporting particles in a carrier fluid, comprising a number of systems as described in claim 1, in which the joint ends of the respective bifurcated glass fibre cables are installed within the channel wall at respective different angles with reference to the vertical direction through the center point of the channel