Hoffrichter CARAT I, Service Manual

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8.5 CHECk ATTACHMEnT OF PRInTED CIRCuIT BOARDS
The controller circuit board is attached to the inner mounting. Subsequently check the attachment
of all PCBs:
• Controller circuit board: 2 screws
• RS232 circuit board: 2 screws
• Power management circuit board: 3 screws
• O
2
metering cell circuit board: 1 screw
8.6 CHECk AIR OuTLET
Check the air outlet (on the rear of the valve manifold) for correct seating, and attention must be
paid to make sure that the synthetic hopper is inserted to the shoulder in the valve base, if neces-
sary correct the seating.
After completion of the task, position the inner mounting in the bottom cover and connect all of the
electrical and pneumatic connections.
During the following tasks, there is a voltage supply to the open machine. The task, therefore,
must only be carried out by authorized, qualified and competent personal. If the service task
is done in the home, the patient must be advised of the dangers.
The following checks are carried out with the machine switched on.
8.7 CHECk THE DISPLAy AnD COnTRAST
Do a check, to make sure that all of the characters are completely and correctly displayed.
The contrast can be adjusted with the assistance of the potentiometer, on the right adjacent to the
display.
8.8 BuTTOn FunCTIOnAL CHECk
Operate the alarm, On/OFF, esc | mode buttons and the MFK to make sure that they function cor-
rectly.
8.9 CALIBRATIOn
A calibration must be carried out in the scope of the annual maintenance, or after a repair of rele-
vant assemblies.
1. Pressure Sensor Calibration
1.1. Install blanking caps on the inspiration connection. Connect the metering tube of one leg of the
T-piece with the pressure metering connection of the CARAT and the second with the pressure
inlet of the APM.
1.2. Press the MFK for an extended period, to get to the “Service” screen.
1.3. There, make the selection menu item “Pressure Sensor Calibration”, enter the appropriate PIn
code and confirm.
1.4. The calibration is carried out at 0, 5, 10, 20 and 40 hPa.