The contactor is a high frequency device
Posted: Thu Dec 12, 2024 10:24 am
It increases the useful life of electrical equipment, as it reduces breakdowns and maintains a balance that helps keep it in perfect condition.
It also protects the power line that supports it.
Operation of thermal relay
As for the thermal relay and its operation , we will try to explain it in a very schematic way, so that everyone can understand it. The device consists of two metal plates joined together by welding. These plates are “permeable”, that is, they are able to react to fluctuations in temperature or electricity. Depending on the materials chosen, they have a different coefficient of expansion.
When the plates expand due to excess heat or power, a small sale leads zimbabwe email address fibre moves and comes into contact with a coil. This, in turn, automatically disconnects the electrical circuit. Until the plates cool down and recover their size, the system will remain off.
It is common for non-electrical professionals to get confused about terms with similar functions. The most common is not distinguishing between thermal relay and contactor . It is true that they are elements with similarities and a similar function, acting as automatic switches that disconnect an electrical system in the event of an overload.
But, there are notable differences between both devices, such as:
, the relay is a low frequency device.
The relay is connected to low power equipment (10A and 15A), compared to a larger range of contactors (from 15A to 12500A).
Relays are smaller devices and therefore cheaper.
Power consumption is higher in a contactor.
Types of thermal relays
Until now we have talked about thermal relays as a whole, and the truth is that there are different types depending on each installation.
Classification can be made based on different factors. The most commonly used is the one that differentiates the thermal relay by its operation .
1. Tripolar
They are probably the most widely used. Their advantage is that they are more permeable and that they operate with the three phases of the current. Thus, depending on their poles, we can distinguish between single-phase, two-phase and three-phase thermal relays . The latter is the one used in solar panels .
2. Compensated
These devices are characterised by the fact that the outside temperature does not affect their operation. They are only activated when they detect variations in the electric current. Therefore, they are the most advisable for installations exposed to extreme weather conditions or environments where it is very cold or very hot.
3. Differential
These are the most sophisticated and precise models, as they detect power cuts in any of the phases and also imbalances between them. They are usually installed in automated installations.
It also protects the power line that supports it.
Operation of thermal relay
As for the thermal relay and its operation , we will try to explain it in a very schematic way, so that everyone can understand it. The device consists of two metal plates joined together by welding. These plates are “permeable”, that is, they are able to react to fluctuations in temperature or electricity. Depending on the materials chosen, they have a different coefficient of expansion.
When the plates expand due to excess heat or power, a small sale leads zimbabwe email address fibre moves and comes into contact with a coil. This, in turn, automatically disconnects the electrical circuit. Until the plates cool down and recover their size, the system will remain off.
It is common for non-electrical professionals to get confused about terms with similar functions. The most common is not distinguishing between thermal relay and contactor . It is true that they are elements with similarities and a similar function, acting as automatic switches that disconnect an electrical system in the event of an overload.
But, there are notable differences between both devices, such as:
, the relay is a low frequency device.
The relay is connected to low power equipment (10A and 15A), compared to a larger range of contactors (from 15A to 12500A).
Relays are smaller devices and therefore cheaper.
Power consumption is higher in a contactor.
Types of thermal relays
Until now we have talked about thermal relays as a whole, and the truth is that there are different types depending on each installation.
Classification can be made based on different factors. The most commonly used is the one that differentiates the thermal relay by its operation .
1. Tripolar
They are probably the most widely used. Their advantage is that they are more permeable and that they operate with the three phases of the current. Thus, depending on their poles, we can distinguish between single-phase, two-phase and three-phase thermal relays . The latter is the one used in solar panels .
2. Compensated
These devices are characterised by the fact that the outside temperature does not affect their operation. They are only activated when they detect variations in the electric current. Therefore, they are the most advisable for installations exposed to extreme weather conditions or environments where it is very cold or very hot.
3. Differential
These are the most sophisticated and precise models, as they detect power cuts in any of the phases and also imbalances between them. They are usually installed in automated installations.