Technical Manual
Page 17
CODEL
OPS.109
Issue : B
Rev. : 1
Date : 23/10/13
Doc. i/d : 0109/6
Ref. : 090028
Figure 10 : Adjustable Mount Details
Minor adjustment may be necessary if the mounting flange has been welded incorrectly.
6.6. Detector Levels
The system uses automatic gain control (AGC). The microprocessor in the signal processor continuously
adjusts the gain of the signals from the two sensing heads to maintain an optimum level for both channels. The
gain settings and detector levels can all be viewed in the Mode 4 Diagnostic display.
There should be no need for a manual gain adjustment. However, should a low channel 1 fault condition or
channel 1 saturation condition occur, it means that the detector levels are outside the range of the AGC system
and the gain of the transducer heads should be increased or reduced respectively.
A gang of four gain switches within each head adjusts the gain of the detector signal. These have a range of x1
to x112. Figure 11 shows the switch locations. The heads are factory set to 4 (switch settings 0100). To change
the gain settings:
Remove the cover of each transducer by unscrewing the four M4 countersunk screws.
Do not
loosen the
cable gland.
Change the gain switch settings as required. The hardware gains are set by a series of dip-switches in
the sensing head.
Re-attach the cover and replace the four screws.
Figure 11: Transducer Gain Switch Location.
Gain switches
UP (OPEN)
= 0
DOWN (CLOSED)
= 1
UP
DOWN