⚠ Relays of phase control: appointment, application, installation, overview of models

In the private sector, particularly if the power wiring was done by an inexperienced specialists, such a problem often occurs in which the voltage on one phase is much lower than indicators on the other. As a result, it begins to break down and the equipment to be 380 V, and household appliances operating from 220V, which is connected to a weak phase. The way out of this situation is to install the phase control relay. What kind of equipment it is connected and what is the - these are the main issues that will be discussed in today's article.

What is the purpose of phase control relays

This equipment is designed to protect the appliances and equipment connected to the three-phase network by monitoring the presence of voltage, its symmetrical and regular alternation. Depending on the functionality, voltage monitoring relays can support a predetermined range, completely cutting off the power on the line, when it is in violation of the upward or downward on one of the phases.

Such equipment is rationally placed where electrical appliances are often switched from line to line, or in the case of Fitting motors in which phase shift causes an increase in temperature and, as a consequence, overheat and burn windings.

How does the voltage monitoring relays, by what principle it works

The device of such equipment includes not only microprocessors that simplify setting the relay and increase its reliability. Also present in the circuit, and circuits which calculate the phase distribution, and control the operation of output contacts in accordance with predetermined parameters.

LEDs on the front panel (the number depends on structural features) to help visually identify the cause of the cutoff. As regards the principle of operation, it can be compared with the united in one body protecting several elements of automation. For example, the disappearance of voltage on one phase of the machine engine begins to warm up. Exceeding a certain temperature triggers the thermal switch, producing a cut-off. However, it is critical modes. Relays of phase control works much earlier, not allowing the motor to heat, which significantly prolongs its life.

Phase separation of the types of control relays

Select the type of phase monitoring relays it depends on the scope of its application. Among them are the equipment EL series:

• EL11 and EL11MT - protect the power supply units, are involved in the ATS systems, power converters and various transformers, generators;
• EL12 and EL12MT - protect the installation, including cranes, with a capacity not greater than 100 kW;
• EL13 - protection of reversible motors of an output not exceeding 75 kW.

Technical characteristics of equipment

When choosing the type of phase control relay should be taken into account the technical characteristics of which are directly dependent on the type of equipment. It makes sense to make out the details of what should be paid special attention.

operating voltage

The widest range of operating voltage has a first type phase monitor - EL11 and EL11MT device. These devices are designed for equipment operating on the network 100, 110, 220, 380, 400 and 415 V. In the second type relay (EL12 and EL12MT) range is modest. It is limited to a voltage 100, 200 and 280 V. A has the smallest range EL13. This relay is designed for a working voltage of 220 V and 380 V.

Limits of operation phase monitoring relays

In the case of the disappearance of one of the phases, the relay works of any type, but when the voltage drops to the cut-off of different types will differ in performance. EL11 series devices are cut-off at 0.7 Ufn, in series EL12 and EL13 this limit is 0.5 Ufn.

Improper phasing can also be a cause of cut-off phase monitoring relays series EL11 and EL12. But EL13 when incorrectly connected phases, does not work, it is also not necessary to lose sight of.

Response time: the cutoff threshold

If the voltage drops below the threshold type of phase control relay may operate through a different time interval. In EL11 models and 12, it is 0.1-10 sec, while the EL13 - 0.1-0.15 seconds.

Operating temperature and its range

EL13 series has the lowest operating temperature range. These models operate at -10 ° C minimum and maximum +45 ° C. As for the series EL11 and EL13, there is a working range is wider. They range from -40 to + 40 ° C.

The mass storage devices and their conditions

The difference in weight is almost negligible. At EL 11 and 12 it is 300 g, and EL13 weighs 250 g Storage temperature relay of any type -60ºS to + 50 ° C.

Advantages and disadvantages of the relay control phase of the Russian manufacture

Many believe that the need to install such equipment is better to buy imported models. However, there is a case where we can remember the saying "where he was born there and handy." Of course, the equipment, "EL" is not without drawbacks, however, and the advantages of these devices are considerable. Let's try to deal with this issue by listing the pros and cons of the relay "EL" to foreign analogues.

Advantages:

Disadvantages:

Popular in the Russian model of phase control relays

The fact that the equipment is "EL" among the Russians the most popular, however. Therefore it is necessary to consider other models that are most known in our country. Among them in the first place phase monitor Zamel CKM-01.

Zamel CKM-01 and its features

This equipment Polish production output has a switching contact and fitted with indicators and asymmetry interlace phases. It is surprising that such a complex device manufacturer had managed to make a simple scheme, using only 2 of the transistor. You can verify this by looking at the photo below.

Zamel CKM-01

Relay domestic producers RNPP-311M

The main feature of the device - the modern compact body and an extended number of settings. Interesting dining options. Here he is independent and is made of each phase. This means that if the supply phase is missing, the device is turned off, and will continue to work from the other in a regular mode.

RNPP-311M does not require user configuration. Factory debugging is close to ideal and suitable for use in various fields. Conveniently and availability indication for each of the phases. The product is mounted on a standard DIN-rail and has a little weight.

RNPP-311M

OMRON K8AB - more functional phase monitoring relays

The line circuit is further included a temporary controller which permits fine tuning. Another "innovation" can be called and that the relay responds not only to the voltage drop, but his jumps. The side panel is a timing chart. The very range consists of four models that provide settings "for everyone."

Relay OMRON K8AB

Carlo Gavazzi DPC01 and its application

Such phase monitoring relays are used in some circuits the power compressors industrial refrigerators. The interesting thing is that the exclusion of the relay circuit, the compressor simply "refuse" to run. Blame low quality supplied to the voltage network. By the way, this is another reason why we should not underestimate the like.

relays Carlo Gavazzi DPC01

Connecting the phase monitor

It should start with the fact that most of the samples of modern equipment is already equipped with such modules and does not require a separate relay. But for older devices and machines such block is required. To begin, we suggest to familiarize with some phase monitor installation diagrams. Although the differences in them are minor and such schemes are contained in the technical documentation for the device, they should consider the overall development.

As for the hardware configuration, then talk about it does not make sense. Each model has its own functionality, and hence the order of debugging actions will be different. You can only give one piece of advice. Do not neglect the careful study of the instructions and the manufacturer's recommendations. They can always be found in the technical documentation for the device.

Final part

Relays of phase control is not mandatory element protective automation. However, if the owner of the equipment does not want to pay for the repair of instruments or at all to spend money on the purchase of new, it is worth thinking about how to install this relay. Because the cost disproportionately lower than price of the same or industrial refrigerator, for example, thicknesser. Here is a case when it makes sense to pay a small fee to subsequently pay tens or even hundreds of times more. No need to purchase costly devices, just buy relay control phase of Russian-made and can not be afraid for the voltage drop or phase imbalance.

We hope that the information in today's article will be helpful to our dear readers. Perhaps for you that something remains unclear, or have any questions in the course of reading. In this case, only required to state in the comments below are from you. HouseChief clarification from the editors and other readers know the subject does not take long to wait.

You yourself use the phase control relay for the protection of their equipment? Write about how it helps you. This information will be very useful to those who only thought about the installation of such a component of the automation. If you liked this article, be sure to rate it. Finally, we offer you to get acquainted with a short video on the topic today.