Normally qualified magnetic locks are usually supplied with two input voltages of 12V and 24V (the difference between single coil and double coil), which are selected and switched through jumpers.
There are several ways to judge the quality of a magnetic lock:
1. Look at the circuit board
Defective magnetic locks can be distinguished from the circuit board. Defective magnetic locks have rough printing, unusually simple planning, no varistors (that is, surge devices, usually two), and only one set is required. Voltage input.
2. Measuring resistance
First unplug the 12V and 24V switching jumpers of the magnetic lock (note: no need to power on), usually there are 4 binding posts (at the jumper), measure the red and black wires, the resistance is about 50 ohms good.
3. Measure the current value after power-on
Connect the magnetic lock to 12V voltage and measure the current value. It is better if the current value is consistent with the marked value. 280KG (600 lb) magnetic lock is usually 400-450 mA better, if it is less than 450 mA, it will not be able to pull; if 24V voltage is applied, its marked value or practical value should be 200 mA.
4. Insulation value
For a qualified magnetic lock, the insulation value of the lock body should be infinite, and the detailed value should be above 50 megaohms; the detailed test orientation is the steel cut piece and the lock body output line (either one).
5. Straightness of the cut steel sheet
In principle, cut steel sheets should be as small as possible to touch with hands or stains. The straightness and parallelism of qualified magnetic lock cut steel sheets should be as standard as possible. The quality of the electroplating of the steel slices depends on whether there are oxidation marks on the steel slices.
6. Glue filling view
The colloid of the magnetic lock should not show bubbles, it should be flat and regular, without cracks, and the point of view is square.
7. Interval between cut steel sheets
The first thing to pay attention to is that the thickness of the steel cut piece should be 0.35mm as the best. At present, most of the steel cut pieces on the market use 0.5mm steel cut pieces; the tighter the steel cut pieces on the lock body, the better, pay attention to the investigation of the steel cut pieces Do not show the appearance of rubber seepage when placed sideways.
8. No residual magnetism
Usually the lock plate of the magnetic lock is made of pure iron, but most of the lock plates are 99% pure iron, so it must have the function of removing residual magnetism. It is equipped with a protruding rubber pad to buffer and have anti-residual magnetism equipment. The lock will drop about 35 kilograms of tension; if you choose 99.9% pure iron products, you can basically remove residual magnetism without anti-residual magnetism equipment, and the pulling force is sufficient.
9, 4007 diode
Specifically refers to locks that do not have indicator lights and signal output. This diode crystal is usually added to the positive and negative poles of the lock’s power supply. This treatment clearly reveals that the lock data is not good enough, and some maintenance tasks are done here to avoid positive and negative poles. The negative pole is connected incorrectly or the access control machine is impacted.
10. Technical disposal of the lock shell
The outer shell of the lock body usually chooses oxidized wire drawing or oxidized sand blasting, especially oxidized sand blasting and fine sand. The wire drawing is regular, the money spraying is even, and the cut surface of the steel shell is flat.
11. High and low pressure
At low pressure, the lock can still work, but the tension drops; when high pressure, the lock body will become hot. At this moment, you should pay attention to the temperature rise. The temperature rise above 20 degrees is a poor product, and the temperature rise data can usually be obtained within one hour.