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bi
b
ag V2.0 Technician’s Manual
P/N 490188 Rev. D
Hydraulic Operation
Dialysis with bi
b
ag
Heated water from chamber E of the hydrochamber flows to the junction of valves 100 and
103. Valve 100 opens and the bi
b
ag will start filling when the dialysate temperature at
temperature sensor 3 reaches 30 degrees C. Valve 100 will close when the pressure
reaches 150mmHg as monitored by the pressure transducer 110. After this initial fill,
valves 104 and 108 open, valve 103 closes, the balancing chamber valves open and any
excess gas generated in the bag is flushed through the hydraulics down the drain. The flow
pump runs and the machine is kept in bypass during this initial flush. Afterwards,
additional water will be added to the bag to maintain pressure in the bag of about 90mmHg.
The conductivity cell (113) and temperature sensor (114) measure the conductivity and
temperature of the sodium bicarbonate concentrate as it leaves the bag. The temperature
compensated conductivity determines the concentration of the sodium bicarbonate
concentrate and the delivery rate of the bicarbonate pump (17).
If air is sensed by the probes (112) in the air separation chamber, valve 101 is
momentarily opened to vent the air.
If the bi
b
ag pressure does not change while the bicarbonate pump is pumping, an airlock
condition is detected. To remove the airlocked condition in the bicarbonate pump, valve
100 opens to pressurize the bag to 150mmHg. Next, the flow is stopped, the balance
chamber valves are opened up, the flow pump runs, and the machine is kept in bypass.
Conductivity cell 117 checks the amount of sodium bicarbonate added to the dialysate
and an error will be displayed if the solution is not within ±5% of expected.
Dialysis with Sodium Bicarbonate Concentrates
Jug bicarbonate dialysis is also supported with the bi
b
ag hydraulics. To run in this mode,
the bi
b
ag connector door must be completely closed and the bicarbonate connector pulled
out. Valves 104 and 108 will open and close based on pressure transducer 110 to allow
bicarbonate concentrate to reach the bicarbonate pump. Conductivity and temperature of
the solution is monitored.
Rinse & Mandatory Rinse
Mandatory rinse is run after a chemical disinfect. Both rinse and mandatory rinse are the
same valve sequence for the valves in the bi
b
ag hydraulics. Valves 104 and 108 alternate
opening every 3 seconds. Valves 100 and 103 alternate opening every 3 seconds. Valve
101 is also opened periodically when conductivity is low. Valve 105 is open.
