At what voltage below 24V will the engine fail to start?

[VanHarper]

24-volt batteries below 21 volts cannot start the vehicle, while above 22 volts can generally start the vehicle. Here are the relevant details: 1. Voltage: The starter motor requires sufficient current and voltage. If the battery is depleted, causing the voltage to drop too low to start the vehicle, a new battery replacement is necessary. 2. After starting the engine: The engine drives the generator, which powers electronic devices and recharges the battery. During charging or discharging, ions in the battery move through the electrolyte, and some ions undergo chemical reactions with the electrolyte as they move.

[DiJaxon]

Having driven large trucks for many years, I know that if the 24V system voltage drops below 20 volts, starting becomes difficult. The starter doesn't have enough power to turn the engine, especially noticeable in cold weather. Low voltage not only prevents starting but can also damage the battery and electrical circuits. There are various reasons: aging battery, insufficient alternator output, or corroded connections. Normally, you can measure the voltage with a multimeter. The standard when stationary is 24-26 volts, and if it drops below 20 volts during startup, you should be alert. Regular battery maintenance and cleaning terminals can avoid the hassle of breaking down on the road, saving time and money on towing. If the voltage consistently falls below 19 volts, seek professional repair immediately—safety first.

[DelEmersyn]

Last time when the 24V bus broke down in the mountainous area, it couldn't start because the voltage was only 18.5 volts, delaying the trip. Experience tells me that the failure rate of starting is high when the voltage is below 19 volts, and it's safer to maintain above 21 volts under normal circumstances. The starter motor in vehicle design requires instant high current, and insufficient voltage will cause it to stall. Checking the voltage daily is simple; measure it before starting, and if it's below 22 volts, charging or inspection is needed. Battery life is greatly affected by temperature, easily losing power in winter and being unstable in summer heat. Proper maintenance can extend its service life. Now I always carry a portable charger for emergencies to avoid similar situations from happening again.

[Eileen]

From a safety perspective, when the voltage of a 24V vehicle drops below 19 volts, it becomes difficult to start, and the risk factor increases. This may be caused by battery degradation, charging system failure, or a short circuit in the wiring. The minimum warning line is around 20 volts, especially if the voltage drops below 18 volts during startup, the vehicle will likely fail to start. Many roadside breakdowns are caused by this issue. It is recommended to check with a simple voltmeter every quarter. If problems are found, do not delay repairs to prevent greater losses, such as expensive generator failures. Simple maintenance like cleaning battery terminals can improve reliability.