AVL AVL DiCom 4000, Service Manual

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Evaluation Unit AVL 4000
4-2 Service Manual
4.1.1 Basic Design
The housing consists of a central metal frame which is drawn up at the front to the inside
front panel which contains the instruments. Inside the frame are the power supply unit,
the main board, optional electronics pcbs, speed/angle board, printer adapter,
pneumatics board and chamber adapter.
The display is mounted on the front panel. The front of the housing consists of 2 plastic
cover sections, the display with integrated plexiglass and membrane keypad and the
printer cover. The printer itself is fitted to the inside front panel.
All of the evaluation unit’s connection sockets are on the right-hand side of the housing.
To cater for the various configurations that require different plugs, the side plate is a
cover plate with the relevant socket symbols printed on it.
If the evaluation unit is used as a four-gas (or five-gas) or combination gas tester, the four-
gas analyzer with integral power supply unit and the pneumatics rear panel are also
integrated.
The pneumatics rear panel is designed so that the four-gas analyzer sits on a metal
bracket and all the pneumatics elements, such as the condensate trap, particulate filter,
measurement and condensate pump, various filters and non-return valve are
accommodated on the rear panel.
The cover closes the entire housing and has built-in finger grips to make it easier to carry.
The screws are situated in the cover in such a way as to permit the housing to be sealed
for official calibration and subsequent sealing purposes.
The four-gas tester can be upgraded to a combination tester by connecting a diesel
measuring chamber, installing the necessary electronics pcb and replacing the back panel.
The display is mounted on the outside of the housing and has a plastic cover. The centre
section of the plastic front has the membrane keypad and an anti-glare, tinted window
through which the LCD display can be seen.
The front panel is suitable for mounting two alternative types of LCD display.
The printer (Epson 5F181) is located on the outside of the housing and (as a dot matrix
printer) sealed in an EMC-quality housing. The paper is fed from above and printed on
the back.
The pcbs are arranged one above the other in the right-hand part of the housing parallel
to the tester base in the following order:
−
main board
−
speed/angle board
−
option board (free slot)
−
The chamber adapter board (for the AVL DiCom 4000) is located on the main
board at slots J4, J6, J10 and J14.
−
The printer board is also on the main board at slots J27 and J28.
−
The pneumatics board is fixed to the rear panel.