Operating and Maintenance Instruction FCU 8000-1 series
Doc.: 3109776 Ed.: 01/13.02.2002
HYDAC Filtertechnik GmbH
E
Page 75
5.4 Function description
Inlet
Outlet
1
2
3
4
5
6
7
8
9
11
10
Display
Keyboard
Printer
R e l a y
Evaluation
Electronics
13
Serial
interface
12
14
15
Figure 2 : Block circuit diagram of FCU
A continuous stream of oil flows through an optical sensor (1), consisting of a laser light
source (2) and a photo receptor (3). The contamination particles present in the oil cause
pulse-type light blockages, which are then classified and counted, according to particle
size, as measurement signals by the evaluation electronics (4).
The measurement of the flow rate, which is required for calculating the contamination
class, is achieved with a built-in flow meter (5), whose signals are also fed to the
evaluation electronics (4).
Finally, the evaluation electronics (4) calculate the number of particles
and NAS or ISO
contamination classes from the signals from the optical sensor and from the flow meter for
the prescribed reference volume of 100 ml.
The continuously acquired measurement values (up to 3000) are also stored here with the
date and time, as a back-up protection against power failure. A real-time clock with battery
back-up is used for this.
