METHOD FOR RECOGNIZING SENSOR POISONINGS AND TEST STATION FOR CARRYING OUT THE METHOD

• US 20140342459A1
• Filed: 05/15/2014
• Published: 11/20/2014
• Est. Priority Date: 05/16/2013
• Status: Active Grant

• Current Assignee: Draeger Safety Incorporated (Dragerwerk AG)
• Original Assignee: Draeger Safety Incorporated (Dragerwerk AG)
• Inventors: BERNDT, Malte, ZASTROW, Dirk, SCHIMMEL, Sven
• Granted Patent: US 9,063,105 B2
• Time in Patent Office: Days
• US Class Current: 436/37
• CPC Class Codes: G01N 2033/0072 by generating a test gas
• CPC Class Codes: G01N 27/16 caused by burning or catalytic oxidation of surrounding material to be tested, e.g. of gas
• CPC Class Codes: G01N 31/10 using catalysis
• CPC Class Codes: G01N 33/007 Arrangements to check the analyser calibrating G01N33/0006

Abstract

A method for recognizing sensor poisonings in portable gas-measuring devices with a test station having a main unit with a control and analysis unit and test modules connected with the main unit for data exchange with an connected device. The test station recognizes device model and/or gas sensor model of the connected device. The main unit has gas inlets for different test gases and there is a first gas feed line for sending test gas to the test modules and a second gas feed line for sending purging gas to the test modules and a gas drain line to return gas from the test modules to the main unit. The method includes detection of a first measured value and of a second measured value and determination of sensor poisoning on the basis of the two values. The test station control and analysis unit carries out the method.

Claims

1. A method for recognizing sensor poisonings of one or more portable gas-measuring devices, the method comprising the steps of:

providing a test station comprising a main unit including a control and analysis unit, a plurality of test modules connected with the main unit, each of the test modules for operative connection with one of the portable gas-measuring devices for data exchange, wherein the test station has device model recognition means for detecting at least one of a device model and gas sensor model of the gas sensor of the gas-measuring device operatively connected to a respective test module, wherein the main unit has a plurality of gas inlets, each of the inlets for one of different test gases, and wherein the test station has a first gas feed line, through which test gas is sent to the test modules, a second gas feed line, through which a purging gas is sent to the test modules, and a gas drain line, through which gas can be sent back to the main unit from the test modules;

connecting at least one gas-measuring device to one of the test modules of the test station;

recognizing at least one of the model of the gas sensor of the gas-measuring device connected and the device model of the gas-measuring device connected by the device model recognition means of the test station;

transmitting, the recognized at least one of the gas sensor model and the device model of the gas-measuring device connected, to the control and analysis unit;

selecting a first test gas, suitable for the gas sensor model of the gas-measuring device connected, by the control and analysis unit;

connecting a gas inlet, of the plurality of gas inlets, through which the selected test gas can be fed, to the first gas feed line;

feeding the first test gas to the test module, to which the gas-measuring device is connected;

detecting a first measured value of the gas sensor of the gas-measuring device;

one of purging and not purging the gas-measuring device and the gas sensor by means of a purging gas, which is sent through the second gas feed line from the main unit to the test module, into which the gas-measuring device is connected;

selecting a second test gas suitable for the gas sensor model of the gas-measuring device connected by the control and analysis unit;

connecting the gas inlet, of the plurality of gas inlets, through which the selected second test gas can be fed, to the first gas feed line;

feeding the second test gas to the test module, to which the gas-measuring device is connected;

detecting a second measured value of the gas sensor of the gas-measuring device; and

determining whether sensor poisoning is present on the basis of the first measured value detected and the second measured value detected, wherein the first test gas contains a gas that is to be measured during the operation of the gas-measuring device at a first, known concentration and the second test gas contains the gas to be measured at a second, known concentration, which is different from the concentration of the gas in the first test gas.

2. A method in accordance with claim 1, wherein the step of determining whether sensor poisoning is present further comprises the steps of:

transmitting the first and second measured values to the control and analysis unit of the test station;

determining a ratio of the first measured value to the second measured value; and

at least one of outputting the ratio by means of an output unit and selecting a follow-up action by the control and analysis unit of the test station on the basis of the ratio determined.

3. A method in accordance with claim 1, wherein the second test gas contains, in addition to the gas to be measured, at least one gas for which the gas sensor model of the gas-measuring device connected has cross sensitivity.

4. A method in accordance with claim 3, wherein the gas to which there is cross sensitivity is not a component of the first test gas.

5. A method in accordance with claim 1, wherein each of the test modules, of the test station provided, comprise a gas feed line, which can be connected with the gas-measuring device to be tested, which has a first feed valve and a second feed valve and which can be connected with the first gas feed line via the first feed valve and with the second gas feed line via the second feed valve, wherein the step of feeding of the first test gas to the test module and the step of feeding of the second test gas to the test module further each comprise the steps of:

closing of the second feed valve; and

opening of the first feed valve.

6. A method in accordance with claim 1, wherein a plurality of gas-measuring devices are connected into the test station at the same time.

7. A method in accordance with claim 6, further comprising the steps of:

for each of the gas-measuring devices, independently carrying out at least one of;

the steps of connecting at least one gas-measuring device, recognizing at least one of the model of the gas sensor and the device model, transmitting, the recognized at least one of the model of the gas sensor and the device model and selecting a first test gas; and

the step of detecting a second measured value;

determining, by means of the control and analysis unit, which of the test modules are equipped with gas-measuring devices and which of the gas-measuring devices need a same test gas as the next test gas;

closing of the feed valve, which is arranged between the first gas feed line and the respective test module, for all test modules that do not need the same test gas; and

for each of the gas-measuring devices, independently carrying out at least one of;

the steps of connecting a gas inlet, feeding the first test gas, detecting a first measured value and one of purging and not purging; and

connecting the gas inlet, of the plurality of gas inlets, through which the selected second test gas can be fed, to the first gas feed line; and

the steps of feeding the second test gas, detecting a second measured value and determining whether sensor poisoning is present, wherein each of the steps of connecting at least one gas-measuring device, recognizing at least one of the gas sensor model and the device model, transmitting, the recognized at least one of the gas sensor model and the device model, selecting a first test gas, connecting a gas inlet, feeding the first test gas, detecting a first measured value, one of purging and not purging, selecting a second test gas, connecting the gas inlet, feeding the second test gas, detecting a second measured value and determining whether sensor poisoning is present is carried out at least once for each gas-measuring device that is connected into a test module of the test station.

8. A test station for recognizing sensor poisonings of one or more portable gas-measuring devices, the test station comprising:

a main unit comprising a control and analysis unit, a plurality of gas inlets for different test gases,

a plurality of test modules connected with the main unit for data exchange with the main module, each of the test modules having a feature for connecting one of the gas-measuring devices;

a device model recognition means for detecting at least one of a device model and a gas sensor model of connected gas-measuring devices;

a first gas feed line through which test gas is fed to the test modules;

a second gas feed line through which a purging gas is fed to the test modules; and

a gas drain line through which gas can be sent back to the main unit from the test modules, wherein the control and analysis unit is configured for;

selecting a first test gas suitable for the gas sensor model of the gas-measuring device connected;

connecting a gas inlet, of the plurality of gas inlets, through which the selected test gas can be fed, to the first gas feed line;

feeding the first test gas to the test module, to which the gas-measuring device is connected;

detecting a first measured value of the gas sensor of the gas-measuring device;

one of purging and not purging the gas-measuring device and the gas sensor by means of a purging gas, which is sent through the second gas feed line from the main unit to the test module, into which the gas-measuring device is connected;

selecting a second test gas suitable for the gas sensor model of the gas-measuring device connected;

connecting the gas inlet, of the plurality of gas inlets, through which the selected second test gas can be fed, to the first gas feed line;

feeding the second test gas to the test module, to which the gas-measuring device is connected;

detecting a second measured value of the gas sensor of the gas-measuring device; and

determining whether sensor poisoning is present on the basis of the first measured value detected and the second measured value detected, wherein the first test gas contains a gas that is to be measured during the operation of the gas-measuring device at a first, known concentration and the second test gas contains the gas to be measured at a second, known concentration, which is different from the concentration of the gas in the first test gas and wherein the recognized at least one of the gas sensor model and the device model of the gas-measuring device is transmitted to the control and analysis unit.

9. A test station in accordance with claim 8, wherein the control and analysis unit is configured for:

carrying out, independently for each of the gas-measuring devices, at least one of;

the steps of connecting at least one gas-measuring device, recognizing at least one of the model of the gas sensor and the device model, transmitting, the recognized at least one of the model of the gas sensor and the device model and selecting a first test gas; and

the step of detecting a second measured value;

determining, by means of the control and analysis unit, which of the test modules are equipped with gas-measuring devices and which of the gas-measuring devices need a same test gas as the next test gas;

closing of the feed valve, which is arranged between the first gas feed line and the respective test module, for all test modules that do not need the same test gas; and

carrying out, independently for each of the gas-measuring devices, at least one of;

the steps of connecting a gas inlet, feeding the first test gas, detecting a first measured value and one of purging and not purging; and

connecting the gas inlet, of the plurality of gas inlets, through which the selected second test gas can be fed, to the first gas feed line; and

the steps of feeding the second test gas, detecting a second measured value and determining whether sensor poisoning is present, wherein each of the steps of connecting at least one gas-measuring device, recognizing at least one of the gas sensor model and the device model, transmitting, the recognized at least one of the gas sensor model and the device model, selecting a first test gas, connecting a gas inlet, feeding the first test gas, detecting a first measured value, one of purging and not purging, selecting a second test gas, connecting the gas inlet, feeding the second test gas, detecting a second measured value and determining whether sensor poisoning is present is carried out at least once for each gas-measuring device that is connected into a test module of the test station.

10. A test station in accordance with claim 8, wherein the gas feed line of each test module is connected fluidically with the gas inlet of a gas-measuring device to be tested when the gas-measuring device is connected into the test module.

11. A test station in accordance with claim 9, wherein the gas feed line of each test module is connected fluidically with the gas inlet of a gas-measuring device to be tested when the gas-measuring device is connected into the test module.

12. A test station in accordance with claim 8, wherein each test module has a gas drain line, which is connectable with the gas drain line of the test station.

13. A test station in accordance with claim 9, wherein each test module has a gas drain line, which is connectable with the gas drain line of the test station.

14. A test station in accordance with claim 10, wherein each test module has a gas drain line, which is connectable with the gas drain line of the test station.

15. A test station in accordance with claim 8, wherein each test module has a gas drain line, which is connectable with the gas drain line of the test station.

16. A test station in accordance with claim 12, wherein the gas feed line of at least one test module has a first feed valve and a second feed valve, wherein the gas feed line of the at least one test module is connected with the first gas feed line via the first feed valve and is connected with the second gas feed line via the second feed valve.