Abstract: A stack (10) of fuel cells (11) is to be tested for tightness of the fuel cell membranes. For this purpose, a tracer gas is introduced into the fuel feed channel (15) of the stack (10). The fuel discharge channel (16) is either open or it is closed. A carrier gas is fed to the feed air channel. (17) and led through the exhaust air channel (18) to a gas sensor (28) where a determination is made whether the carrier gas contains amounts of tracer gas. A defective fuel cell (11) can be located by introducing a lance comprising a sniffing probe into the corresponding channel (18) and determining the position of the probe.

Abstract: The sniffing leak detector comprises a sniffing probe, a suction device and gas detector. An operator-activated switch initiates the beginning of a measuring operation. The switch starts a time measurement, wherein an alarm signal is generated by a signal transmitter at the end of a predetermined measuring period. The sniffing leak detector allows for an operator guidance from measuring point (MP) to measuring point, wherein the measuring period is predetermined and an adherence to the measuring period is monitored.

Abstract: A leak detector comprising a base appliance provided with a gas detector, a vacuum pump, and a control device. A sniffer probe is connected to the base appliance. A test leak device containing the supply of test gas is arranged in a separate sub-housing. The sub-housing also contains a temperature sensor, a processor, and a data memory. The processor corrects the measured temperature according to a sample, and modulates the light of a light barrier. The processor is connected to the control device in the base appliance by a data cable.

Abstract: A stack (10) of fuel cells (11) is to be tested for tightness of the fuel cell membranes. For this purpose, a tracer gas is introduced into the fuel feed channel (15) of the stack (10). The fuel discharge channel (16) is either open or it is closed. A carrier gas is fed to the feed air channel. (17) and led through the exhaust air channel (18) to a gas sensor (28) where a determination is made whether the carrier gas contains amounts of tracer gas. A defective fuel cell (11) can be located by introducing a lance comprising a sniffing probe into the corresponding channel (18) and determining the position of the probe.

Abstract: The leakage search assembly has a main device which contains a vacuum pump and a test gas sensor, and a hand-held sniffing probe. Capillary lines which connect the sniffing probe to the basic assembly contain valves by means of which these lines can be selectively opened. In a leakage search mode, the capillary line having the larger cross section is open. This results in leaks also being found from a greater distance. The dead time before response of the test gas sensor is shortened. Once a leak has been located, the assembly is switched to the leakage rate measurement mode, in which only the capillary line with the smaller cross section is open. This results in quantitative determination of the leakage rate with high accuracy and high stability.

Abstract: The leakage search assembly has a main device which contains a vacuum pump and a test gas sensor, and a hand-held sniffing probe. Capillary lines which connect the sniffing probe to the basic assembly contain valves by means of which these lines can be selectively opened. In a leakage search mode, the capillary line having the larger cross section is open. This results in leaks also being found from a greater distance. The dead time before response of the test gas sensor is shortened. Once a leak has been located, the assembly is switched to the leakage rate measurement mode, in which only the capillary line with the smaller cross section is open. This results in quantitative determination of the leakage rate with high accuracy and high stability.

Abstract: The sniffing leak detector comprises a sniffing probe, a suction device and gas detector. An operator-activated switch initiates the beginning of a measuring operation. The switch starts a time measurement, wherein an alarm signal is generated by a signal transmitter at the end of a predetermined measuring period. The sniffing leak detector allows for an operator guidance from measuring point (MP) to measuring point, wherein the measuring period is predetermined and an adherence to the measuring period is monitored.

Abstract: A leak detector comprising a base appliance provided with a gas detector, a vacuum pump, and a control device. A sniffer probe is connected to the base appliance. A test leak device containing the supply of test gas is arranged in a separate sub-housing. The sub-housing also contains a temperature sensor, a processor, and a data memory. The processor corrects the measured temperature according to a sample, and modulates the light of a light barrier. The processor is connected to the control device in the base appliance by a data cable.

Abstract: A sampling leak detector which comprises a basic device and a sniffling probe connected thereto via a tube. A visual display is located on the sniffling probe. A tactile indicator is provided in a handle. An acoustic indicator is arranged on the basic device. The detector can be switched to a detection mode in which the color in the visual display changes and the indicator are activated when a predetermined leakage rate is exceeded. The detector can also be switched to a locating mode in which leakage rate information is displayed by means of a bar of variable length and a sound is generated which has a parameter depending on the leakage rate information.

Abstract: A leak test apparatus includes a housing having an interior sized for retaining a plurality of instrument components including a control unit. A sniffer gun is linked to the instrument components, the sniffer gun having an intake point, and a test leak includes a gas reservoir, a constriction, an opening suited for introducing the intake point of said sniffer gun, and a temperature sensor. The temperature sensor is linked, either by means of a wired connection or wirelessly to the control unit for signal transfer.

Abstract: A leak test apparatus includes a housing having an interior sized for retaining a plurality of instrument components including a control unit. A sniffer gun is linked to the instrument components, the sniffer gun having an intake point, and a test leak includes a gas reservoir, a constriction, an opening suited for introducing the intake point of said sniffer gun, and a temperature sensor. The temperature sensor is linked, either by means of a wired connection or wirelessly to the control unit for signal transfer.