卷帘门非常怕的不是下雨生锈，是它明明已经喊了三次救命，老板还在拿手推。

The biggest fear of rolling shutter doors is not rusting in the rain, but the fact that they have already called for help three times and the boss is still pushing them with his hands.

第一次警告：遥控按下去，电机“嗡”一声但不转。

First warning: Press the remote control, the motor will beep but not turn.

十次里有七次是启动电容鼓包，几块钱一个的小零件，换掉就能好。很多人这时候不去换电容，反而连按十次，结果电容烧穿、电机绕组一起报废，维修费直接从几十块跳到上千。

Out of ten times, seven of them are for starting capacitor bulges. Small parts that cost a few yuan each can be replaced. Many people do not replace the capacitor at this time, but instead press it ten times in a row, resulting in the capacitor burning through and the motor winding being scrapped, and the repair cost jumping from tens of yuan to thousands.

第二次警告：门升到一半突然停住，或者下降时咔咔响。

Second warning: The door suddenly stops halfway up or makes a clicking sound when descending.

这是限位器跑偏了。上限位过高会冲顶、下限位过低会砸地。找到电机旁边的限位调节螺丝，慢速试跑三次校准就行。一直不调，帘片脱轨、卷轴变形，下次就不是调螺丝能解决的。

This is a deviation of the limiter. If the upper limit is too high, it will rush to the top, and if the lower limit is too low, it will hit the ground. Find the limit adjustment screw next to the motor and run it slowly for three calibrations. If it's not adjusted, the curtain will derail and the scroll will deform. Next time, it won't be solved by adjusting the screws.

第三次警告：手拉门觉得非常沉，或者松手自己往下滑。

Third warning: The sliding door feels particularly heavy, or release yourself and slide down.

扭簧的预紧力没了。扭簧是整扇门的平衡系统，门体重量全靠它扛，电机只是起步用。弹簧断一根建议成对换，只换一边，旧的那根很快也断，而且断裂瞬间会带着卷轴弹回来，非常危险。卡在半空时千万别用手拽帘片，也别让店员站门下抬头看——先断电，再叫人。

The pre tension force of the torsion spring is gone. The torsion spring is the balance system of the entire door, and the weight of the door is entirely carried by it. The motor is only used for starting. If one spring breaks, it must be replaced, only one side needs to be replaced. The old one will also break quickly, and the broken one will immediately bounce back with the scroll, which is very dangerous. When stuck in mid air, do not pull the curtain with your hands, and do not let the salesperson stand under the door looking up - power off first, then call someone.

平时顺手做三件事，能多用好几年：

Doing three things casually can help you use them for several more years:

导轨每个月用毛刷清一次砂石，别等异响才处理，石子卡在滑轮里一天就能磨出槽。

Clean the sand and gravel on the guide rail once a month with a brush. Don't wait for any abnormal noise before dealing with it. If the gravel gets stuck in the pulley, it can be ground out in a day.

链条和轴承每半年上一次锂基脂，别用普通黄油，粘灰结块反而卡死。

Apply lithium grease to the chain and bearings every six months. Do not use regular butter as it may stick to dust and clumps, causing them to get stuck.

遥控器半年换一次电池，别等有效没电。很多“遥控坏了”只是电池亏电，换电池能省一次上门费。

Replace the battery of the remote control every six months, don't wait until it runs out completely. Many 'remote controls are broken' simply because the battery is running low, replacing the battery can save one visit fee.

顺手一条红线：下雨天控制箱别裸着。电机和控制盒加个防雨罩，济南夏天雷阵雨多，进水一次控制板就废，比门体本身还贵。

A red line: Don't expose the control box on rainy days. Add a rain cover to the motor and control box. In Jinan, there are many thunderstorms in summer, and once the water enters, the control board becomes useless, which is even more expensive than the door itself.

把“嗡声先查电容、卡位调限位、扭簧成对换、导轨月月清”这四句贴在卷门机旁边，很多门能多撑三五年，不会在某天早上开门时直接掉下来。

Stick these four sentences next to the door rolling machine: "Check the capacitor first for buzzing sound, adjust the limit of the card position, replace the torsion spring, and clean the guide rail every month". Many doors can last for three to five years without falling off directly when they open one morning.