With 28 v batteries for power supply, circuit board equipment if the battery is negative short circuit, will damage the circuit board? If it is damaged, then what is the principle of damage? How to avoid? Thank you very much!

CodePudding user response:

Under normal circumstances, the battery short circuit will not damage the battery power supply circuit, electrical equipment, but also the phenomenon of some exceptions, such as:
1: short circuit occurred during high temperature, the explosion and fire on the battery, the environment, be destructive power supply equipment,
2: the short circuit point in the power supply circuit board (due to short circuit welding, wrong line, etc.), large current through the circuit board PCB, heat damage producing PCB,
3: relatively far away from the circuit board, battery with long cable power supply, cable short circuit, short circuit occurred in near the battery is away from the board, in the case of short circuit short-circuit point after high temperature melted the short-circuit point metal short circuit disconnection, the moment cable can produce high voltage to the circuit board damage (broken after long cable is equivalent to inductance, inductance current produces the high pressure), the damage need to release a diode in the circuit board input protection,
4: the battery short circuit are also likely to be damage to the circuit board of battery charging circuit, need to add a short circuit protection charging,

CodePudding user response:

reference 1st floor qq_708907433 response:

normally, battery short circuit will not damage the battery power supply circuit, electrical equipment, but also the phenomenon of some exceptions, such as:
1: short circuit occurred during high temperature, the explosion and fire on the battery, the environment, be destructive power supply equipment,
2: the short circuit point in the power supply circuit board (due to short circuit welding, wrong line, etc.), large current through the circuit board PCB, heat damage producing PCB,
3: relatively far away from the circuit board, battery with long cable power supply, cable short circuit, short circuit occurred in near the battery is away from the board, in the case of short circuit short-circuit point after high temperature melted the short-circuit point metal short circuit disconnection, the moment cable can produce high voltage to the circuit board damage (broken after long cable is equivalent to inductance, inductance current produces the high pressure), the damage need to release a diode in the circuit board input protection,
4: the battery short circuit are also likely to be damage to the circuit board of battery charging circuit, need to add a short circuit protection, charging

I see, very detailed, thank you,

CodePudding user response:

refer to the second floor - c - s - d - n - response:

Quote: refer to 1st floor qq_708907433 response:

normally, battery short circuit will not damage the battery power supply circuit, electrical equipment, but also the phenomenon of some exceptions, such as:
1: short circuit occurred during high temperature, the explosion and fire on the battery, the environment, be destructive power supply equipment,
2: the short circuit point in the power supply circuit board (due to short circuit welding, wrong line, etc.), large current through the circuit board PCB, heat damage producing PCB,
3: relatively far away from the circuit board, battery with long cable power supply, cable short circuit, short circuit occurred in near the battery is away from the board, in the case of short circuit short-circuit point after high temperature melted the short-circuit point metal short circuit disconnection, the moment cable can produce high voltage to the circuit board damage (broken after long cable is equivalent to inductance, inductance current produces the high pressure), the damage need to release a diode in the circuit board input protection,
4: the battery short circuit are also likely to be damage to the circuit board of battery charging circuit, need to add a short circuit protection, charging

See, very detailed, thank you,

3 kinds of circumstances, if the circuit board short-circuit point distance is far, does not damage the board? Because the short-circuit point to produce high pressure, after a long wire pressure drop, to the circuit board, there is no high pressure, is that right?

CodePudding user response:

Short-circuit point of near and far, in fact, is the size of the cable inductance
Short-circuit point near the batteries, cables short, small inductance, inductance energy storage is small, the high pressure is low, the damage is small,
Short-circuit point away from the battery, long cable and inductance, inductance energy storage, high pressure is high also, damage is big,
Pressure drop and long wire it doesn't matter,
Long wire mainly inductance characteristic,
Short-circuit point, of course, you're far from the board, if produce high voltage, inductance characteristic in long cable, inductance filter characteristics, to the circuit voltage is not high, (not resistance step-down, inductance filter)

CodePudding user response:

reference 4 floor qq_708907433 response:

short-circuit point distance, is actually the size of the cable inductance
Short-circuit point near the batteries, cables short, small inductance, inductance energy storage is small, the high pressure is low, the damage is small,
Short-circuit point away from the battery, long cable and inductance, inductance energy storage, high pressure is high also, damage is big,
Pressure drop and long wire it doesn't matter,
Long wire mainly inductance characteristic,
Short-circuit point, of course, you're far from the board, if produce high voltage, inductance characteristic in long cable, inductance filter characteristics, to the circuit voltage is not high, (not resistance step-down, inductance filter)

Uh-huh, I see, thank you!