Cds Pressure Switch - Fresenius Medical Care 4008 E Technical Manual

3.3.6

CDS pressure switch

Measuring equipment: Measurement setup according to diagram,
Place of measurement: Hydraulic unit open
Condition:
Check/adjustment:
– Connect the measuring equipment as illustrated in the diagram.
– Select the DIAGNOSTICS menu:
READ INPUTS
READ DIGITAL INPUTS
CPU1: RD DIGITAL INP
I: CPU1_PSW_V102 or I: CPU1_PSW_104
– Activate the audible alarm by pressing the (Alarm) Tone Mute key (depressurized: alarm on).
– During these menu options, the solenoid valves MV102 and MV104 are closed.
– Use the syringe to create a pressure of 0.7 bar.
– Use forceps to clamp the line at point a, so that the pressure switch remains loaded with
0.7 bar.
– Verify the switching point by means of the audible alarm
Rated values:
Alcatel pressure switch (part no.: 674 322 1) (yellow): 0.68 – 0.80 bar
Delta pressure switch, dark grey:
Envec pressure switch:
If the switching point deviates, adjust with the adjusting screw b (make sure there is no
mechanical load on the pressure switch while adjusting).
– After completed adjustment, depressurize the measuring equipment and repeat the check. If
necessary, repeat the adjustment procedure.
This adjustment procedure simultaneously checks the tightness of the check valves 117 and 118
and the solenoid valves 102 and 104.
UMED, HMED or pressure gauge (e.g. 0 to 1 bar, accuracy ±1 %),
syringe
The CDS connectors in position 121 and position 122 must be depres-
surized.
The pressure compensation port on the pressure switch must be open
to air (atmospheric pressure).
The lines of the measuring equipment should be as short as possible.
The service mode must be selected.
Fresenius Medical Care 4008 4/08.03 (TM)
0.68 – 0.72 bar
0.68 – 0.72 bar
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