Power plant on board
The electricity supplier is the generator, while the starters, fans, controllers, lamps and heaters are the consumers. The battery resembles a bank card, the bill that melts with each start of the engine and is topped up with the help of a generator.
If this does not happen, the battery card will soon be reset and you will therefore no longer receive “credit” for the next engine start. However, this happens in life, when you spend more than you earn.
Battery almost empty? The cause may be the generator which, if the car gets stuck in a traffic jam, cannot supply all consumers with power at the same time.
Old machines can’t handle it
Is there sufficient generator power to supply all consumers (headlights, windscreen wipers, heating) with power when the combustion engine is running at minimum idle speed? A few decades ago, the magazine “Behind the Wheel” made measurements on cars of that time: the energy balance was checked on the Volga GAZ-3110 (with a ZMZ-4062 engine) and on the Zhiguli VAZ-2104.
The overall result was disappointing: at the minimum idle speed, car generators could not supply all regular consumers with energy, and therefore the batteries began to discharge. The same thing happens in slow traffic jams: headlights are on, fans are buzzing, music is playing loudly and generators are barely spinning.
What about modern?
Even the layout shows that cars that are stuck in traffic use a lot of energy.
We checked the editors Largus with a range of 136 thousand km: we warmed up the engine and turned on everything that could handle, from high beams to windshield wipers. However, everything is in order: the on-board voltage was 13.2 V and the battery has been charged successfully.
Do the generators supply normal power to all consumers when the combustion engine in other cars is running at minimum idle? Or does the battery always start to discharge under such circumstances?
We asked representatives of leading car companies.
Comments from car manufacturers
Jaguar Land Rover
Jaguar and Land Rover vehicles have a system for monitoring and monitoring the battery charge level. Depending on the condition of the battery, the operation of a particular vehicle system will be limited to prevent battery discharge and to keep the battery in a state that guarantees stable starting of the car.
The balance of electricity in a car is calculated during design and depends on many factors. Engineers are not faced with the task of ensuring continuous simultaneous operation of all electricity consumers on board for an unlimited period of time.
There will be no battery discharge.
A good alternator ensures normal operation. Otherwise, a message will appear and the associated warning light will illuminate to indicate a malfunction.
The assistant “generator manager” in the engine control unit always provides the required battery charge and controls the ICE operating mode depending on the power load of the attachments.
There is no battery discharge.
Under the conditions of a warm and serviceable car, when the engine is idling, the generator ensures the normal operation of all regular consumers that are turned on at the same time. And maintains battery charge to allow subsequent engine start.
Don’t the reactions of Jaguar Land Rover, Volvo and Hyundai sound cautious? For example, the generator may not supply all consumers with power at the same time.
Denis Zagarin, Head of the NAMI Test Center
There are no separate requirements for generators
There are no separate requirements for the assessment of the energy balance and generators in the vehicle. If we talk about generators as spare parts, then according to clause 94 of Appendix 10 of TR CU 018/2011, the following requirements are imposed on them:
- performance in environmental conditions;
- performance when voltage changes;
- electromagnetic compatibility;
- vibration and shock resistance;
- protection against the ingress of dust and moisture;
- dielectric strength of insulation.
The answer from Jaguar Land Rover is therefore indicative. But not all cars (especially cheap ones) have similar systems that turn off consumers.
Stock pocket not pulling?
Is it really impossible to make sure that in every car, even at minimum idle speed, the generator can “supply” everyone?
The fact is that it was designed on the principle of reasonable adequacy. And since the car is still made for driving, not being stuck in a traffic jam, the generator is also only calculated for the average consumer, who alternates standing in a traffic jam with normal traffic on the highway.
Attempts to increase the generator’s performance (reducing the gear ratio between the crankshaft and the generator pulleys) will revert to the rapid wear of the bearings at high speeds (it’s not all the time to be in traffic jams!). Installing a deliberately more powerful generator is always extra kilograms, rubles and liters of fuel.
As the load increases, the generator slowly begins to “ground”, reducing the output voltage. If a voltmeter is installed in the car, it is easy to follow. Battery charging continues, but at a lower voltage. In the future, the voltage of the generator and the EMF of the battery can become equal – charging stops. As the load increases further, the battery begins to discharge.
How not to drain your battery
The limit below which the voltage should not drop is about 12.7 V.
If you notice that the voltage in the on-board network drops under load (the headlights dim, the voltmeter readings decrease), it is advisable to check the voltage on the battery terminals (when the engine is at minimum idling and the maximum number of consumers).
The normal voltage in the vehicle electrical system must be 13.8 – 14.2 V. If the voltage rises to the indicated values during the shutdown and there are no complaints about the state of the on-board network (oxidized contacts or poor alternator belt tension), then you should take into account: in traffic jams at maximum load, your car battery cannot cargo accept more. So a consumer in such a situation has to be sacrificed.
- Do you want to save? A wide selection of spare parts and consumables under the Za Rulem trademark allows you to do this. The full range and list of sellers can be viewed via the link.
- “Behind the wheel” can also be read in Yandex.Zen.
Such cases are not isolated. We understand the reasons and listen to the opinion of car manufacturers.
The battery is discharged in the summer – why? The experts explained everything
Source: Z R