we will tell how the speed of the universal motor of a washing machine is controlled under 1300 rpm. The complete step by step procedure How many volts it takes, how its direction is changed, how can you actually control it with simple components to run this machine at its maximum power.
Lambda sensor / oxygen sensor: operation
This small probe, which could almost pass for a technical detail, is in fact an important component for the proper functioning of the engine (especially modern ones) and their efficiency. Here are the important things to remember about the operation and role of the lambda sensor, also called oxygen sensor.
How it works ?
The purpose of this sensor is to indicate to the computer the level of oxygen in the exhaust gases, this allows you to know if the ratio between fuel and oxidizer is good. A lack of fuel (lean mixture) leads to the destruction of the engine (too much internal heat, there is even an additional temperature sensor in the exhaust to properly detect the lean mixture) and the appearance of NOx, while that a rich mixture (too much fuel) induces poor combustion and excessive amounts of pollutant emissions (not to mention clogging of the engine and catalyst).
The lambda / oxygen sensor emits a more or less high voltage depending on the oxygen level, it generally goes from 0 to 1 Volt on narrow band sensors, and 0.5 Volt (0.5 Volt then indicating an ideal richness of 1. And for example 0.9 being lean and 1.2 being rich) indicates correct richness (proportion of 14.7 doses of oxidizer/air for 1 dose of fuel in the case of a petrol engine for example). Depending on what the computer receives, it will more or less modify the opening time of the injectors. The probe detects the oxygen level because its coating (exposed to the exhaust gases) in titanium dioxide sees its electrical resistance naturally change according to the quantity of oxygen which is in contact with it.
Catalyst
Lambda probes (there may be only one or even three to further refine the data for the ECU. The more modern the car, the more there are). In reality, the first probe upstream of the catalyst is used for the air/fuel ratio (richness), and the second is used to check that the catalyst is properly treating the exhaust gases. This second results from the EOBD standard which allows the display of the engine warning light in the event of a problem, precisely to prevent that there are excessive pollutant emissions (this is also failed at the technical inspection).
Exhaust manifold
Thanks to this data, the computer will estimate the precise dose of fuel to send to the cylinders to reach the ideal ratio between oxidant (oxygen) and fuel (gasoline/diesel) which is 14.7 units of air for 1 unit of fuel ( which is 9 units of air to 1 unit in the case of ethanol). The computer, which controls the injection, will send each time a dose of fuel which will make it possible to reach this ideal ratio called stoichiometric.
If the air rate is higher than this proportion (gasoline engine), the mixture will be qualified as lean (ex: 14.7 of air for 0.8 of fuel) while conversely it will be qualified as rich (ex: 14.7 of air to 1.2 of fuel or even 13 of air to 1 of fuel).
If the measurement of this ratio is correct, the lambda probe will return a value of around 1 (which then corresponds to a perfect ratio of 14.7 to 1) . Beyond 1, this means that the mixture is too lean, which induces overconsumption and pollution. Below 1 it is the opposite: the mixture is rich.
The lambda probe therefore allows better engine efficiency, which leads to reduced consumption, less pollution and protection for the catalyst (which does not like excess smoke at all from the exhaust, it clogs it).
Several types: narrowband and wideband lambda
To function properly and deliver reliable information, the lambda must be at a high temperature. If on the old engines it was necessary to wait until the car was warm (the engineers also placed the probes closer to the engine to promote the rise in temperature), the new probes are now heated, or rather they have a resistance in them which allows to heat it up. As a result, it becomes operational very quickly, a few seconds after starting.
There are other differences and versions. The most basic lambda is short band: quite basic since it only indicates whether the mixture is lean or rich (voltage emitted from 0 to 1 Volt depending on richness). The wide band probe (0 to 5 Volt depending on richness) makes it possible to precisely indicate the oxygen level to the computer, even on lean or rich ranges.This type of sensor will be used on modern lean-burn gasoline engines (e.g. stratified) or even on diesels, without forgetting that it is an advantage if you wish to switch your gasoline engine to ethanol (a wide band makes it easier to manage the different types of fuel). It is obviously more expensive than the basic narrow-band one and to work well (or rather for the computer to use it correctly) it needs to know the reference value in the air (the oxygen level in the surrounding air ) using another probe
Petrol only?
Originally only gasoline engines had it because diesels operate on excess air, so there was no need to adjust the oxidizer/fuel ratio. However, diesel engines becoming more and more sophisticated (it is especially the anti-pollution standards that require this), this data is now of interest to the computer to make the fuel injection work as well as possible, but also the EGR valve which sends back part exhaust gases to the intake. Let's not forget either the systematic appearance of turbo which also leads to a better understanding of the oxygen level (in order to control the wastegate as well as possible).
Faulty lambda sensor?
When the latter no longer sends the correct information or when it does so randomly, the computer tends to detect it. In this case, it puts the operation of the injection by default and increases the fuel rate (ratio between fuel and air) to avoid any mechanical risk. Indeed, if the computer can no longer know the oxygen level, it will manage without it, as on old engines.
If it returns erroneous values, the computer may be mistaken about the control of the injection, the throttle body (petrol) or even the EGR valve.
we will tell how the speed of the universal motor of a washing machine is controlled under 1300 rpm. The complete step by step procedure How many volts it takes, how its direction is changed, how can you actually control it with simple components to run this machine at its maximum power.
Lambda sensor / oxygen sensor: operation
This small probe, which could almost pass for a technical detail, is in fact an important component for the proper functioning of the engine (especially modern ones) and their efficiency. Here are the important things to remember about the operation and role of the lambda sensor, also called oxygen sensor.
How it works ?
The purpose of this sensor is to indicate to the computer the level of oxygen in the exhaust gases, this allows you to know if the ratio between fuel and oxidizer is good. A lack of fuel (lean mixture) leads to the destruction of the engine (too much internal heat, there is even an additional temperature sensor in the exhaust to properly detect the lean mixture) and the appearance of NOx, while that a rich mixture (too much fuel) induces poor combustion and excessive amounts of pollutant emissions (not to mention clogging of the engine and catalyst).
The lambda / oxygen sensor emits a more or less high voltage depending on the oxygen level, it generally goes from 0 to 1 Volt on narrow band sensors, and 0.5 Volt (0.5 Volt then indicating an ideal richness of 1. And for example 0.9 being lean and 1.2 being rich) indicates correct richness (proportion of 14.7 doses of oxidizer/air for 1 dose of fuel in the case of a petrol engine for example). Depending on what the computer receives, it will more or less modify the opening time of the injectors. The probe detects the oxygen level because its coating (exposed to the exhaust gases) in titanium dioxide sees its electrical resistance naturally change according to the quantity of oxygen which is in contact with it.
Catalyst
Lambda probes (there may be only one or even three to further refine the data for the ECU. The more modern the car, the more there are). In reality, the first probe upstream of the catalyst is used for the air/fuel ratio (richness), and the second is used to check that the catalyst is properly treating the exhaust gases. This second results from the EOBD standard which allows the display of the engine warning light in the event of a problem, precisely to prevent that there are excessive pollutant emissions (this is also failed at the technical inspection).
Exhaust manifold
Thanks to this data, the computer will estimate the precise dose of fuel to send to the cylinders to reach the ideal ratio between oxidant (oxygen) and fuel (gasoline/diesel) which is 14.7 units of air for 1 unit of fuel ( which is 9 units of air to 1 unit in the case of ethanol). The computer, which controls the injection, will send each time a dose of fuel which will make it possible to reach this ideal ratio called stoichiometric.
If the air rate is higher than this proportion (gasoline engine), the mixture will be qualified as lean (ex: 14.7 of air for 0.8 of fuel) while conversely it will be qualified as rich (ex: 14.7 of air to 1.2 of fuel or even 13 of air to 1 of fuel).
If the measurement of this ratio is correct, the lambda probe will return a value of around 1 (which then corresponds to a perfect ratio of 14.7 to 1) . Beyond 1, this means that the mixture is too lean, which induces overconsumption and pollution. Below 1 it is the opposite: the mixture is rich.
The lambda probe therefore allows better engine efficiency, which leads to reduced consumption, less pollution and protection for the catalyst (which does not like excess smoke at all from the exhaust, it clogs it).
Several types: narrowband and wideband lambda
To function properly and deliver reliable information, the lambda must be at a high temperature. If on the old engines it was necessary to wait until the car was warm (the engineers also placed the probes closer to the engine to promote the rise in temperature), the new probes are now heated, or rather they have a resistance in them which allows to heat it up. As a result, it becomes operational very quickly, a few seconds after starting.
There are other differences and versions. The most basic lambda is short band: quite basic since it only indicates whether the mixture is lean or rich (voltage emitted from 0 to 1 Volt depending on richness). The wide band probe (0 to 5 Volt depending on richness) makes it possible to precisely indicate the oxygen level to the computer, even on lean or rich ranges.This type of sensor will be used on modern lean-burn gasoline engines (e.g. stratified) or even on diesels, without forgetting that it is an advantage if you wish to switch your gasoline engine to ethanol (a wide band makes it easier to manage the different types of fuel). It is obviously more expensive than the basic narrow-band one and to work well (or rather for the computer to use it correctly) it needs to know the reference value in the air (the oxygen level in the surrounding air ) using another probe
Petrol only?
Originally only gasoline engines had it because diesels operate on excess air, so there was no need to adjust the oxidizer/fuel ratio. However, diesel engines becoming more and more sophisticated (it is especially the anti-pollution standards that require this), this data is now of interest to the computer to make the fuel injection work as well as possible, but also the EGR valve which sends back part exhaust gases to the intake. Let's not forget either the systematic appearance of turbo which also leads to a better understanding of the oxygen level (in order to control the wastegate as well as possible).
Faulty lambda sensor?
When the latter no longer sends the correct information or when it does so randomly, the computer tends to detect it. In this case, it puts the operation of the injection by default and increases the fuel rate (ratio between fuel and air) to avoid any mechanical risk. Indeed, if the computer can no longer know the oxygen level, it will manage without it, as on old engines.
If it returns erroneous values, the computer may be mistaken about the control of the injection, the throttle body (petrol) or even the EGR valve.
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