Treaton MPR6-03, Руководство пользователя

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2.5 Measurement of CO
2
, O
2
and Anesthetics Concentration
120

leakage in the sampling system due to worn parts;

incorrect measurement of the zero level due to gas leakage in the area after the
pump;

malfunction of the zero valve, the valve does not open as a result;

too high moisture content of the sample due to aging of the Nafion filter tubes;

contamination of the measuring chamber due to ingress of moisture;
If you have any doubts on the measurement accurace make the following tests:
A) Checking the tightness of the pneumatic path of the gas analysis module

When the sampling line is connected to the water trap, tightly close the inlet end of the line
for a short time. It should lead to the display of a message about the path occlusion and in-
creasing of the sound of the pump. In case of leak in the path there is no reaction. When a
message about path occlusion appears, it must be removed to prevent the gas analysis
module from being turned off.

If there is no message about occlusion, repeat the test with disconnecting the sampling line
from the water trap and blocking the water trap inlet directly. If you see a message about oc-
clusion, the cause of the loss of tightness should be looked for in the sampling line or in its
loose joint with the water trap nipple.

If in this case there is no message about occlusion, repeat the test with disconnecting of the
water trap and blocking both device’s nipples. If you see a message about occlusion, the
cause of the loss of tightness should be looked for in the water trap or its loose connection
with the device fittings (e.g. wear of the O-rings on the fittings).

If the reason for the loss of the path tightness is inside the device, contact the service to find
and eliminate it.
If during the tightness test the path is closed for a long time, then after the
purge attempt
the diagnostic message “Long occlusion!" appears. After re-
moving the blockage, the message is cleared and the module switches to
the measurement mode.
B) Checking the gas concentration measuring accuracy of the gas analysis module
For the test you may use one-component gas mixtures (with a precisely known concentration of
the reference gas, but not less than 1.5%). For example, 5% CO2 with nitrogen filling the rest of
the volume. It is necessary to check the accuracy of the concentration measurement of at least
one more gas measured by the gas analysis module. It is allowed to use a multicomponent gas
mixture, for example, recommended by the manufacturer of the gas analysis module: 3% Des,
5% CO
2
, 50% N
2
O, 42% O
2
.
Make the following steps:

Connect the cylinder with the reference gas mixture to the sampling line of the device
through the T-shaped connector (T-piece). The volume of the tee should be minimal (up to 2
ml). One of the outlets of the tee must be connected to the atmosphere to prevent damage to
the device by cylinder pressure. It is recommended to connect a flow meter (rotameter) to
this outlet to control the flow rate (up to 200 ml / min).

Turn on the device, warm it up for at least 10 minutes to switch to the full accuracy mode. In
the menu for setting of the gas analysis module parameters, set the units of measurement in
%.

Open the shut-off valve of the cylinder with the reference gas mixture, set the flow at about
200 - 250 ml/min according to the flow meter (rotameter). Check the readings of the detected
gases on the device screen.

Wait 30 s for the reading to stabilize.