Connect the electromagnetic lock

Advantages and disadvantages of the conventional locks forget the buying solenoid. Expenditure of power 5W create stress 350 kg (Falcon EyE). Good enough to just put the equipment correctly. Let us rather see how the electromagnetic lock connection.

electromagnetic lock apparatus

Seen in paragraph reception job magnetic crane. 5 watts of power will keep more than a third of a ton, how to believe? Athletes train for years, most of the deadlift is unable to lift the weight, power is required... 5 W 5 J / s, a little more than 1 cal, every hour goes... 4 kcal 1 gram of sugar. Great? 1 gram of sugar keeps a third of a ton per hour! Supernatural powers of the electromagnetic lock is available. energy costs are so low, comparable with the light illuminating the staircase. LED resting ...

Interestingly principle of electromagnetic lock! - The first question, brain storm. We begin the study of the design, creating the force. Inside the castle is worth electromagnetic coil entwine core W-shaped, the edges protrude outward, one can touch it, opening the front door key. electromagnetic lock womb is filled with compound, standing inside the coil. Internals exhausted electromagnetic lock. The formula states: the force holding the stationary steel plate fixed on the door depends on:

• Mutual contact area and the core plate;
• The number of turns wound wire;
• Current.

Since the resistance of the electromagnetic coil purely ohmic lock is obtained, the power voltage depends determined. By increasing the voltage increases the current in accordance with Ohm's law (I = U / R). Power most electromagnetic locks is a network of 12 volts. Some manufacturers draw graphs of the holding force of the voltage. It can be seen: the curve quickly rises to 10 volts, then gradually bends, becomes parallel to the x-axis (horizontal). Excessive increase in the power coil is strongly heated. Compound prevents cool, prevents service.

Desperate to find a power supply 12 VDC, put current limiting resistor. The goal of reducing the load on the electromagnetic lock. We measure the coil resistance tester (at the terminals). After we ask ourselves calculation, based on the simple ratio: Uzamka / Urezistora = Rzamka / Rrezistora. Remember, in the amount of Uzamka, Urezistora given supply voltage, Uzamka ultimately equals 12 volts. Let us consider an example:

1. Assume controller board, intercom feed 24 volts DC.
2. Measurement tester have shown that the resistance of the lock coil is 30 ohms.
3. Solve the proportion of 12/12 = 30 / Rrezistora. Uzamka Urezistora = + 24 volts.
4. How do we find the resistor required 30 ohms. Take the E24 series resistance (see. Review About marking resistance and capacitance, eg, here). The accuracy of the nominal value of 5%. If we take the 33 ohms, the power lock retention will drop by 5%. Therefore it's better to work under higher voltage, if the resistance has a bias toward the lower side.
5. It is time to calculate the power dissipation. Divide the 12 volt squared at 30 ohms, 4.8 watts is obtained, roughly 5. circuit resistors are marked with a Latin numeral V. Look for items here http://www.eliron.ru/catalog/rezistory/. Shtudiruet Aliekspress. Over five hundred will take a few hundred pieces. Will be sent to the department of the Russian mail.

Electromagnetic locks may be repaired. Compound is not available, remove and replace the spool. The core, glued strips of electrical steel sheet. It intended to reduce the effect of residual magnetization. There are solid cores of soft magnetic materials. Residual effect is higher. Heating does not take place, a constant current. Heat generation due to two phenomena:

1. Magnetization reversal steel alternating field. Formed a residual effect after switching off the current in the electromagnetic lock.
2. The eddy currents (Foucault).

Both phenomena are eliminated by special measures. The currents are blocked lacquer insulation between the plates, electrical steel weakly magnetized. It does not eliminate the residual effect at all. If the core is solid. Often electromagnetic lock inside the large-capacity capacitor is connected in parallel inductors (above 200 uF). After disabling the voltage oscillating circuit is formed, generates alternating current, discharging through the winding.

The direction of the field changes direction quickly. The current decays, the energy is spent on the magnetization reversal of the core. Voltage drops quickly, the door is opened without any problems. Otherwise, the residual magnetism phenomenon can greatly spoil the lives of people. Not only physically weak. Capacitor fails, the door began to open only bodybuilders - it's time to put a new non-polar capacitance, parallel terminals castle.

Price gizmos reaches 250 rubles. Watching what model of the capacitor take. It remains to add that the phenomenon of self-inductance when power is turned off is a strong self-EMF (reminds commutator motor), causing arcing in the external buttons, relays. Avoiding reducing the service life of the mating equipment, choose a controller equipped with output stages of electronic keys: transistors, thyristors of various types. Blocking effect provides Deacon (DIAC - symmetrical diode thyristor), a current limiting in both directions (smoothes fluctuations), arcing is suppressed fundamentally.

Install the electromagnetic lock

Firstly, there are castles, working in open or short circuit voltage. It is proposed to set the correct jumpers. The number of output terminals is increased to five:

• Two contacts is used for supplying power (e.g., 12 volts).
• The three will serve as a contact switch, it is believed to use two of them. COM (common) always works, another condition is defined by the rule: if the button will, the controller in the normal position are closed or open.

According to choose controller. Lock type described previous subsection, produced by the OLEVS simply controlled by the presence of food. Before installation, find out:

1. Is there a double-sided blanking restrictive thyristor.
2. It is built into the electrical capacitance blocking residual magnetization.
3. Behavior of the castle, the methods management options.

Do not forget the equipment often need to be matched with an intercom. The controller is provided with an input unlocking the touch of a button (including standing at the door to the street). Often lock is operated in darkness, well, if there is a power supply terminal of the backlight LEDs on the front control panel intercom. The visitor can immediately see where to put the magnetic key.

Please note: for reasons of low magnetization steel plate, mounted on the door, practically devoid of dopants. Almost vulnerable to corrosion. Plant protective coating is applied:

• Paint is the cheapest option. A layer of thick, short-lived. Increasing the distance between the steel plate and a lock reduces the force of gravity.
• Zinc is called compromise. The layer obtained durable, beautiful. The pressing force of the electromagnetic lock falls, decreased the increased gap.
• The most expensive, high-quality coating of nickel is considered. Beautiful, resists rust. As a ferromagnetic nickel is attracted lock. Therefore, little reduces the pressing force.

Steel rust - avoid pulling, waiting until problems begin. Take fine sandpaper, Clean of corrosion, varnished. Of course, the familiar imeysya exploiting domestic installations of anodization of the metal contact. Get zinc chloride - a question of technique. You can get hold of nickel, highlighting finances. There are folk remedies, such as emulsion was prepared by adding paraffin candles in kerosene.

"If the contact pad door sealed with adhesive tape, it is possible entrance is marked upcoming robbery. The technique thieves mercilessly exploited for illegal entry on another's territory. Would be bypassing the management company, call the police, ask the necessary questions. The cops will understand. Self-adhesive tape to remove useless to paste over. The increase in the gap between the pad, lock reduces the force of gravity. Thieves will be able to open the door with his bare hands. "

Electromagnetic lock can be installed on the jamb. It was convenient, looked nice. For the best fit for each screw used two goals from the shoal - steel, top - rubber. It allows the pad a little wiggle, firmly adhering to the core. Hexagon screw TORX not longer break. Before you connect the electromagnetic lock, select the installation option:

1. The lock is placed on the top jamb with the inner portion, the core for the door. Pad mounted in front. Additional attachments are required.
2. If the door is glass, transparent, it is permissible to mount the pad lock inside. The steel plate is replaced by the Z-shaped area. It is assumed, the door opens into the room.
3. Too narrow jamb, if you can not put the electromagnetic lock of the door is allowed to expand the surface area. Lead assembly on top, as in the first version.
4. Sometimes the door must be opened to the side with which the castle stands. Pad should be positioned horizontally along the top. It is carried out by means of brackets. Similarly, the plate is placed horizontally. The gap is minimal. Understandably, it is difficult to calculate, but it is convenient to use the trim washers. Note that the door warps, system performance is disturbed.
5. The last-described method can be completed with decorative PVC profiles on the perimeter. Arrange it so that the electromagnetic lock has been hidden.

With any of the techniques readily combine video intercom connection with the electromagnetic lock. But most often used first. Wiring diagram of the electromagnetic lock is entirely dependent on the control (as it should be clear), and some more, and there is a switch to select the power supply voltage. So what would happen is something to smash his head.

Then, a binding (connection) to the electromechanical lock keys subscribers. This is done through the controller. To simplify the process of using the master key, but that's another story. That's all they wanted to say about the intercom connection with electromagnetic lock.