Analyze the misunderstanding of three roller gates | swing gates | wing gates and other access control systems

Common Mistakes Occurred in Access Control Constructions Misunderstandings of a three-roll gate, a swing gate, and a wing gate, etc.

1. Use a network cable to lock the cable to the controller!

2. Power load is too heavy! Mainly manifested as too many electric locks!

3.485 communication lines can not take the star connection, must go to the standard hand-in-hand bus mode.

4. Other considerations.

A common phenomenon in the construction of access control is the use of a network cable to lock the controller to the line!

A section of the line from the electric lock to the controller in the construction of the access control looks very ordinary. If it is not standardized, it is easy to cause the fault phenomenon that is difficult to find. This must be taken seriously!

Because the operating current of the electric lock is relatively large (as opposed to other devices of the access control system such as the controller card reader), the electric lock has a certain distance from the controller, and the voltage drop on the line will be relatively large. If the pressure drop is too large, the electric lock can sometimes be held in motion, sometimes with no movement. Magnetic locks are sometimes not enough suction. The performance of the door switch is not normal. Even with the controller to grab current resources, making the controller power supply is insufficient, restart or even crashes.

Some engineering personnel have convenient wiring or convenient purchasing. It is very easy to cause faults by using the network cable to electrically lock the wires of the controller. Although it seems that there is no problem during debugging, after a while, problems will often arise. .

From the electric lock to the controller, if the line length is less than 50 meters, a two-core power cable with a cross-sectional area of ​​1.0 mm2 is required, and no shielding is required. If the cable length exceeds 50 meters, double a multi-core power cord and parallel the power supply. If the line length is greater than 100 meters, it is recommended to move the controller closer to the door lock to shorten the wiring distance. The cross-sectional area of ​​the network cable is 0.2 square millimeters, which is 5 times smaller than our standard wire, so it is absolutely impossible, even if the controller is close to the electric lock. Electric magnetic signal cable, you can use network cable. Some people will connect the four strands of the network cable and provide power to the electric lock. Although it is theoretically close to the norm, it is not recommended to do so. Doing so will make the terminals unstable and other hidden dangers.

The common error phenomenon of access control construction II - excessive load power load! Mainly manifested as too many electric locks!

The power configuration of the access control system suggests that the standard configuration power supply is a 12v3a switching power supply. He can meet (wired specification, wire cross-sectional area is thick enough under the premise) up to two doors (2 electric locks or magnetic locks) power supply. A double door magnetic lock translates to the power of two single door magnetic locks. If the system exceeds this configuration, for example: more than 2 electrical plugs or more than 2 magnetic locks need to add a power supply and the original power distribution. Note: If some of the electric lock power is too large, the power supply will have a weaker load capacity.

If electricity is not enough, it will not necessarily show up when debugging, unless it is not enough. The performance is sometimes that the door is locked, sometimes it is not locked, and even the controller may snatch the current, causing the controller to restart or even crash.

Common mistakes in access control construction Three 485 lines do not use twisted pair, or use low-end passive converters! The 485 communication line cannot take the star connection, and it must go through the standard hand-in-hand bus mode.

Other matters needing attention 1. Without consulting and understanding, unauthorized access to some of the non-access control system itself equipment (such as automatic doors or elevators and the like); each external device, and even different manufacturers of the same device have different electrical characteristics, if Unfamiliar with these characteristics, it is very easy to cause instability of the access control system, but also generate a lot of interference, so please connect with the technical staff of the access control factory before making external equipment, get some experience, but also to strengthen the external equipment The familiarity of electrical performance, as well as the improvement and precipitation of engineers' own technical experience.

2. When the customer sometimes refers to replacing this product with other products, the wiring has been laid out. When the line cannot meet the specification requirements, the line must be re-arranged, and the standard cannot be used. At this moment, saving time or getting lucky will inevitably put a heavy price and effort on future work.

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