The intelligent charger adopts a three-stage pulse charging mode to better protect the battery Stage I: constant current charging Stage 2: constant voltage charging Stage 3: Trickle charging Finally: During the charging process, the built-in fan automatically turns on to cool the charger. The battery is fully charged and the charger stops automatically How to select a suitable charger 1. Check the parameters on the original charger: voltage and current 2. Look at the parameters of lithium battery: our charger is suitable for 48v 13 series lithium battery pack. The charger socket is XLR male, and the corresponding battery interface should be XLR female 3. The charging interface electrode is: 1+2 -, which is suitable for most brands of lithium batteries, but there are also a few brands with different electrodes. If the electrode cannot be confirmed, it can be confirmed in advance There may be the following reasons for the charger not working after connecting to the power supply: 1. The voltage and current of the charger do not match your battery. You have purchased a charger with wrong parameters. Please tell us the brand and model of your electric bicycle or the parameters and plug of the original charger. 2. Due to the limited life of the lithium battery, the charger will not work if the battery is damaged. Your battery may be damaged if it is not used for more than 12 months or 2-3 months. 3. If the green light comes on when the power is turned on, but the LED light does not turn red after the battery is connected, the connector should be loose and in poor contact, and the plug can be re inserted to maintain good contact 4. If there is a green light when plugged into the power supply, and the light goes out after connecting the electric bicycle, it is because of the internal short circuit of the electric bicycle, which causes the charger to have a self-protection function. You'd better check your e-bike battery and replace it.