ļ 2002 by ELTRA GmbH Germany ā January 2002 ā Service Manual OH 900 / ON 900 / ONH 2000
1.15-1
1.15
1.15
Malfunctioning of the electronic drivers:
IC 2, 3, 4 and 5 are electronic driver
integrated circuits, found on the mother
board inside the electronic unit.
Their type No. is ULN 2803 or
TD 62083.
These ICs act as a power switch, in
order to energise solenoid valves inside
the analyser, see 4. 3;
or to send control signals, see 1.2, 1.13,
and 1.14
Operation range of the driver ICs.
Depending on the fault location, the following driver ICs need to be replaced:
IC b: Furnace start ( see 1.13 and 2.16 ), purge valve ( see 4. 3 )
IC c: Motor for sample drop ( see 1.14 and 2.18), furnace open / close ( see 4. 3 )
IC d: Furnace on / off ( see 1.13 and 2.16 )
DRIVER
DRIVER
DRIVER
DRIVER
J1
V G - c o n n e c t o r 9 6 - p o l e
IC c
IC d
IC a
IC b
1-6
IC a-d
+24V
Output
load
+24V
b1-b32
a17-a26
VG plug