Magnetic locks should be identified from various technical indicators. Standard qualified magnetic locks generally provide 12V and 24V input voltages (the difference between single coil and double coil), which are selected and switched by jumpers. To judge the pros and cons of a magnetic lock, there are several ways:
1. Circuit board: Inferior magnetic lock can be judged from the circuit board. The inferior magnetic lock circuit board is rough printed and the layout is extremely simple. There is no varistor (that is, the surger is generally two), and only A set of voltage inputs.
2. Measure the resistance: first unplug the 12V and 24V switching jumpers of the magnetic lock (note: no power is required), generally have 4 binding posts (jumper), measure the red and black lines, and the resistance is It is better to be around 50 ohms.
3. Measure the current value after power-on: After the magnetic lock is passed through the 12V voltage, the current value is measured, which is better than the labeled 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 The insulation value of the lock body should be infinite, the specific value should be above 50 mega ohms; the specific test position is the steel cutting piece and the lock body output line.
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 distance: The main concern is that the thickness of the steel cutting piece should be 0.35mm. Most of the current market use 0.5mm steel cutting piece; the tighter the steel cutting piece on the lock body, the better. , pay attention to observe the arrangement of the steel cutting piece, do not appear in the phenomenon of seepage.
8. No residual magnetism: The lock piece of the general magnetic lock is made of pure iron, but most of the lock piece is 99% pure iron, so it must have the function of demagnetizing, and it has a protruding rubber pad to cushion the function. The lock with anti-remaining magnetic device will reduce the pulling force of about 35 kg; if 99.9% pure iron product is used, the residual magnetic force can be basically eliminated without the anti-residual magnetic device, and the pulling force is sufficient.
9.4007 diode: especially refers to the lock without the indicator light and signal output. Generally, this diode crystal is added at the positive and negative poles of the power supply of the lock. This treatment obviously shows that the material of the lock is not closed, but some protection work is done here to prevent The positive and negative poles are connected incorrectly or impact the access control machine.
10. Process treatment of the lock body shell: The lock body shell is generally made of oxidized wire drawing or oxidized sand blasting, especially by oxidizing sand blasting, and fine sand is superior. The wire drawing is neat, the banknote is evenly sprayed, and the cutting surface of the outer steel body is flat.
11. High and low pressure: When the pressure is low, the lock can still work, but the pulling force is reduced; when the pressure is high, the lock body will be hot. At this time, attention should be paid to the temperature rise. If the temperature rise exceeds 20 degrees, it is inferior, usually within one hour. Get the temperature rise data.
12. Acidity test: It is coated with a weak acid on the lock steel cutting piece. The good lock body will not oxidize after 45 minutes, and the difference usually shows oxidation in 15 minutes. In addition, the lock body can be soaked in water, and it is inferior to black in 24 hours.
13. Finish: Drop the small drops on the lock steel to observe whether the flow is smooth, whether it is muddy or not, and the smoothness is excellent.
14. Lock body plating: pay attention to the plating quality of the corners of the lock body. Wrinkles and darkness are caused by the lock body plating.
15. Output line: The two cores are no signal output electric lock, and the five cores are with door position detection output.