Instruction manual

NGA 2000 MLT Hardware
TEST PROCEDURE / TEST POINTS
11 - 2
Emerson Process Management GmbH & Co. OHG
Instruction Manual
90002929
07/2006
“+” “-” “A” “ ”
R11
(IR)
R5 (UV)
R1 (UV)
Fig. 11-2: PCB "VVS"
11.1.1 Internal Voltage Supply
Test point: “+” or “-” of detector PCB “VVS”
(Fig. 11-2)
Measuring instrument: Digital voltmeter
Signal: ≈ + 6,2 V dc at test point “+”
≈ - 6,5 V dc at test point “-”
Failure: No signal
Possible reason: Detector not connected to PCB “PIC” (Fig. 1-20) or PCB “DSP” (Fig. 1-21)
External voltage supply absent
Internal / external power supply defective (Fuses ?)
PCB “PIC”/“DSP” not correctly connected to PCB “ICB” / defective
No “+” voltage from the PCB “PIC”, in fast of a ground loop of the
physics (connection physics → housing, must be ∞)
11.1.2 IR Source
Test point: Connector of IR source
Measuring instrument: Ohmmeter
Signal: ≈ 6.8 Ω to 8.6 Ω between the two cables
Failure: incorrect values
Possible reason: Source defective
Light source is cold:
For more - IR - channel analyzer interchange the light sources.
Replace the suspect light source (see Section 17.2).
INTERNAL VOLTAGE SUPPLY / IR SOURCE