Fifteen ways to judge the pros and cons of fake and inferior magnetic locks

The design of the magnetic lock (or electromagnetic lock) is the same as that of the electromagnet. It uses the principle of electromagnetism. When the current passes through the silicon steel sheet, the electromagnetic lock will produce a strong suction force and tightly attract the adsorption iron plate to achieve the effect of locking the door. . As long as the small current electromagnetic lock will generate a great magnetic force, the access control system that controls the electromagnetic lock power supply will be powered off after the correct identification personnel, and the electromagnetic lock will lose its suction to open the door.

Standard qualified magnetic locks generally provide 12V and 24V input voltages (the difference between single and double coils), which are selected and switched by jumpers. To judge the pros and cons of a magnetic lock, there are several ways:

1, look at the circuit board

The inferior magnetic lock can be judged from the circuit board. The inferior magnetic lock circuit board is rough and the layout is extremely simple. There is no varistor (that is, the surger is generally two), and there is only one set of voltage input.

2, measuring resistance

First remove the 12V and 24V switching jumpers of the magnetic lock (note: no power is required), generally there are 4 binding posts (jumpers), measure the red and black lines, and the resistance is about 50 ohms. good.

3. Measure the current value after power-on

It is better to measure the current value after the magnetic lock is passed through 12V voltage, which is consistent with the marked value. The magnetic lock of 280KG (600 lbs) is generally 400-450 mA. If it is less than 450 mA, it is not enough. If it is 24V, the marked value or actual value should be 200 mA.

4, insulation value

The standard qualified magnetic lock should have the insulation value of the lock body as infinite, and the specific value should be above 50 mega ohms; the specific test position is the steel cutting piece and the lock body output line (either one).

5, the verticality of the steel cutting piece

In principle, the steel cutting piece should be minimized by hand touch or stained. The standard of the perpendicularity and parallelism of the qualified magnetic lock steel cutting piece is better. The quality of the steel cutting plate should be checked by the presence or absence of oxidation marks on the steel cutting piece.

6, glue inspection

The colloid of the magnetic lock can not appear bubbles, should be flat and tidy, no cracks, and the angle is square.

7, cutting steel distance

The main concern is that the thickness of the steel cutting piece should be 0.35mm. Most of the current market uses 0.5mm steel cutting piece; the closer the steel cutting piece on the lock body is, the better the tightness is. Do not appear in the alignment.

8, no residual magnetism

Generally, the lock piece of the magnetic lock is made of pure iron, but most of the lock pieces are 99% pure iron, so it is necessary to have the function of demagnetizing, and has a protruding rubber pad for buffering function and anti-remaining device. The lock will reduce the pulling force of about 35 kg; if 99.9% pure iron is used, the residual magnetism can be basically eliminated without the anti-residual magnetic device, and the pulling force is sufficient.

9,4007 diode

Specifically, the locks that do not have the indicator light and the signal output are generally added to the positive and negative poles of the power supply of the lock. This treatment obviously reveals that the material of the lock is not closed, and some protection work done here to prevent positive and negative Extremely wrong or impact access control, etc.

10, the process of the lock body shell

The lock body shell is generally made of oxidized wire drawing or oxidized sandblasting, especially by oxidizing sandblasting, and fine sand is superior.

Editor in charge: Xu Yuehua