The success rate of automobile emergency power supply is related to capacity. Generally, the capacity of the automobile starting power supply should not only be looked at. Capacity is related to discharge rate, starting current and number of starts. There are two recommended options. One is to modify it yourself, but you need to have certain knowledge of electronics, 30C maximum discharge rate of 60C, 2 in parallel (preferably 3 in parallel) 4 strings, which requires 8 or 12 batteries. A single battery costs around 6 yuan, and batteries cost between 60 and 90 yuan. Use a high-power soldering iron to solder copper wires, preferably at least 16 square millimeters, and the output line should be at least 16 square millimeters of copper wire, passing through binding posts of 200 A and crocodile clips. I made a set for a friend and a set myself, in Cilizing a 3-parallel-4-series solution, and there is no pressure to start a 3.5 displacement Kia utility vehicle in winter without a battery on the car. Starting alone should also be fine. The second option is to purchase finished products, using 3 cells of Hitachi 40900 lithium batteries. The price of 3 cells of connection cables is about 105 yuan, and you need to equip them with output cables, alligator clips , chargers, etc. For both solutions, the charger must use a balanced charge, or use a protective plate with a balanced charge.
Differential protection of braking characteristics versus ratio simply means that the set value of the differential current increases by a certain ratio as the braking current increases. This allows the braking current to have a braking effect in the event of an external fault with large unbalanced current. In the event of a faultdull, the braking effect is minimal. As the main protection of double and three turn transformers, the differential protection with relative braking characteristics has the advantages of reliable action and collection, calculation, comparison and judgment in real time practical and simple.
In simple terms, the braking effect is to prevent the protection from starting and to prevent the protection from starting. Relative braking is to prevent the protection from starting when an external fault occurs. unbalanced current collected To increase the protection starting current. This prevents the differential from tripping in the event of an external fault and widens the power cutoff range.
With the increase in the external short circuit. current, the braking amount of the differential relay increases, and the action The current also increases, ensuring that when an external short circuite occurs, the differential protection does not work, but when an internal fault occurs, the differential protection works sensitively
The differential protection of braking characteristics relative simply means that the setting value differential current changes with braking. Increasing the current causes some increase in the ratio. This allows the braking current to have a braking effect in the event of an external fault with large unbalanced current. In the event of an internal fault, the braking effect is minimal. As the main protection of double and three turn transformers, the differential protection with relative braking characteristics has the advantages of reliable action and collection, calculation, comparison and judgment in real time practical and simple.
In simple terms, the braking effect is to prevent the protection from starting and to preventexpensive protection to start. Relative braking is to prevent the protection from starting when an external fault occurs. unbalanced current collected To increase the protection starting current. This prevents the differential from tripping in the event of an external fault and widens the power cutoff range.
With the increase in the external short circuit. current, the braking amount of the differential relay increases, and the action The current also increases, ensuring that when an external short circuit occurs, the differential protection does not work, but when an internal fault occurs, it works sensitive manner