AVL AVL DiCom 4000, Service Manual

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4000 4-/5-Gas Measuring Instruments Unit
Service Manual 5-15
Primary error symptom Primary cause
(of error)
Secondary cause of
error Possible tests/
establishing cause Remedy
Communication
error
RS232 cable, Andros
measuring
instruments unit
faulty
Cable connected
incorrectly
Service mode:
pumps and valves
can be switched but
no measurement
values. Check cable
connections Connect cable
correctly or replace
measuring
instruments unit
Zeroing in service
mode Not an error; can
take up to 80 sec
Measurement cell
faulty/soiled
Condensate end of
pump is faulty.
Condensate
discharge tube is
clamped closed
Raw values for CO,
H, CO
2
lower than
80000.
Check hoses, test
flow rate
(faster than 2
min
l
per channel)
Clean or replace
pump
Clean or replace
measurement cell
Replace measuring
instruments unit
Faulty light source Light source faulty,
power supply unit
faulty
UC raw values in
service mode lower
than 10000
ES not zero
Light source does
not light up Replace light source
Replace measuring
instruments unit
No measurement
values displayed but
chopper is working
Faulty detector UC raw values in
service mode lower
than 10000
ES not zero Replace detector
Replace measuring
instruments unit
Faulty transformer
Faulty fuse Power supply,
pneumatics board or
pump Normal:
resistance of
transformer
windings approx.
50
Ω
, very high
resistance to ground
Replace transformer
(465)
Replace fuse
Faulty power
supply Disconnect power
supply, measure
transformer
resistance Change power
supply
Faulty pneumatics
board (465) Faulty driver on
board Driver on
pneumatics board/
cooling element is
very hot Replace measuring
instruments unit
Replace board
Replace transformer
too if necessary
Mains short circuit
Faulty pump Short circuit in
pump electronics
(465) Disconnect pump,
measure
transformer
resistance (approx.
50
Ω
normal),
ground fault?
Replace pump