866.4.Maxtec www.maxtec.com22
11.3 Gas Outlet
There are three gas outlets on the MAXBlend2. One is a fixed acrylic flow meter,
the other two are auxiliary ports (one on the bottom of the unit and one on the
right side). These outlets are capable of delivering combined metered flows of
0-30 LPM for the low flow model (R229P01) and 0-120LPM for the high flow
model (R229P02). The auxiliary outlet ports are fitted with an automatic shut off
valve. The flow of gas from either outlet port is automatically initiated by attaching
a pneumatic device (such as a flow meter) to the outlet port.
Regardless of whether or not the outlet has any device connected to it, a
minimal gas bleed flow of 0.1 LPM flows form the MAXBlend2 sensor port on
the left side of the blender. It is from this bleed flow that the gas is analyzed by
the oxygen sensor. In addition a toggle switch is provided allowing the user to
activate an additional gas bleed which ensures the blender has sufficient flow to
function accurately when the total flow delivered to the patient is below a certain
minimum threshold. For a low flow model (R229P01) this additional bleed
should be activated if the total flow delivered to the patient is less than 3LPM.
For a high flow model (R229P02) the additional bleed should be activated if the
total flow delivered to the patient is less than 15LPM. At delivered flows greater
than these limits, the bleed toggle can be deactivated to conserve oxygen.
CAUTION: Failure to activate the bleed as described above may result in significant drift
in the oxygen concentration delivered to the patient.
11.4 Alarm/Bypass Function
The MAXBlend2 includes a pressure differential alarm which provides an
audible alarm if gas source pressures differ by 20 PSI (1.3 BAR) (nominal) or
more, or if there is a gas supply failure of one of the source gases. This alarm is
generated by a reed alarm located in a cap on the bottom of the MAXBlend2.
The primary purpose of the alarm is to audibly warn the operator of an excessive
pressure drop or depletion of either source gas pressure. Should both gas
pressures increase or decrease simultaneously, an alarm will not activate.
If either source gas pressure drops, the outlet pressure will drop similarly as the
mixed gas is always balanced to that of the lower gas source.
The gas bypass function operates in unison with the alarm. Once the pressure
alarm is activated, the bypass function is actuated and the gas with the higher
pressure flows directly to the outlet port, bypassing the mixing function of the
MAXBlend2. The oxygen concentration flowing out of the MAXBlend2 will be that
of the gas with the higher pressure. In the alarm/bypass mode, the blender will
deliver oxygen (100%) or medical air (21%) until pressures have been restored to
a differential of 6 PSI or less (0.4 BAR).
To Next Page
Loading...
Need help?
General