Generator Load: Key Questions & Answers

Hi,

What can one understand from this measurement?

Is this a load indicator showing the percentage (0...100%) at which the generator regulator is operating?
To provide the necessary energy?

Or is that the additional load that the MSG has to bear (due to a longer injection time)?
to increase the generator's speed?

At idle, it is typically around 50-60%, and the lower the engine speed, the lower the load (up to about 10%).

If that were the case, one would need to connect an external charger to the 'load.'
Is it possible to visibly minimize it even when idling?

A large generator (90/120A) produces more load in the second stage than...
a smaller one (70A), since larger masses/heavier objects are harder to turn?

How much larger should a generator be compared to the battery?

I, for example, don't really see the point of having a small 1.4-liter engine with a 60 Ah battery.
to 'torture' a 90 A generator - even if it has a climate control system .
A 90-amp generator, even when the battery is completely discharged (let's say only 70%), would...
A generator running at approximately 90% capacity would be ideal, but how often does the battery actually run completely empty?

It's clear that the generator doesn't produce its full power output when idling.
'But what is a 120A generator doing in a small load, with a reported 60% load?'
Even if we assume it only delivers half of its maximum power, and...
Of that, 60% would be around 40 amps - do cars consume that much power these days?
Without using any power-consuming features except the engine (climate control, lights, rear window defroster are off).

The generator load in the MWB (Main Water Brake) is simply the duty cycle of the DF (Dynamo Field) terminal.
So, a proportional measure of the excitation current, and therefore the former.

Quote:

It is clear that the engine does not produce its full power when idling. "But what is a 120A generator doing in a small load, with a reported 60% load?" Even if we assume it only delivers half of its maximum power, and... Of that, 60% would be around 40 amps - do cars consume that much power these days? Without consumers, except for the engine (climate control, lights, rear window off)

You need to consider the 100% value in relation to the maximum generator power output at the current rotational speed.
Therefore, the load also decreases as the speed increases. The generator could potentially produce more power. However, the electricity consumption doesn't increase.
Set the engine speed to 0 (turn off the engine) and turn on the ignition, then see what appears .
Then it's running at 100% capacity, but it's still not accomplishing anything.

So, as I said, it's just the current caused by the pathogen.

vagtuning wrote:

For example, I don't see much point in "torturing" a small 1.4-liter engine with a 60 Ah battery using a 90 A generator - even if it has air conditioning . A 90-amp generator, even when the battery is completely discharged (let's say only 70%), would... A generator running at approximately 90% capacity would be ideal, but how often does the battery actually drain completely? It's clear that the generator doesn't produce its full power output when idling. "But what is a 120A generator doing in a small load, with a reported 60% load?" Even if we assume it only delivers half of its maximum power, and... Of that, 60% would be around 40 amps - do cars consume that much power these days? Without consumers, except for the engine (climate control, lights, rear window off)

Well, let's put it this way: It should definitely be possible to drive at a low RPM in the height of summer, with the headlights and air conditioning on, without draining the battery.

Calculation example:
- Low beam headlights, all around ~ 15A.
- Climate coupling (no idea), maybe 5A.
- Interior fan at medium speed: 10A.
- Radiator fan set to level 2, 30A, due to high summer temperatures and uphill driving.
- Radio 5A
- Motor with peripherals, 5A.

Sum: 70A.

Considering that the listed 90A output of the battery charger isn't achieved across the entire RPM range, it's easy to see that it's often operating at its limit with just 70A. And if you add a caravan with a 10A refrigerator plus additional tail lights, or a cooler, a large Hi-Fi system, or something similar, even the lowest setting of the radiator fan will struggle to provide enough power.

It's no coincidence that most 1Z and other vehicles use a 120A fuse. This has little to do with the battery's capacity, but rather with the constant power draw of the various electrical components.

Regards,
Sure, here's the translation:

"Guste" is a German word that means "gust" or "gust of wind." It can also be used to describe a sudden burst of something, such as laughter or anger.

I wasn't expecting so many questions, but thank you for clarifying everything.
Okay, I'll leave the 120 where it is; it seems like it might be useful after all.
I thought this might be an option that is a) cheaper and b) perhaps more suitable.
It might still save some fuel, but it seems to have its purpose.

The 120A power output is not achievable at the typical diesel engine speed range. That's why it always displays "xx/xxx A". The first power level is reached at 1800 RPM (generator shaft), and the second at 6000 RPM on the generator shaft. The gear ratio should be approximately 1:2 to 1:3, if I remember correctly from the documentation.

1:2 should fit. Then, 1800 generators are running at diesel idle.

My BMR once made a very slight squealing noise with the serpentine belt (because I spilled a bit too much water in the engine compartment), and it immediately increased the idle speed noticeably.

For informational purposes only, at this point:

"How much power does the MSG consume? I'm just curious about the power consumption when only the motor is running, with all comfort features turned off, meaning no radio, ventilation, or lights."

Then, roughly speaking, components like the ABS (Anti-lock Braking System), MSG (Multi-function Steering Wheel), airbags, and the vehicle's onboard network would require power. What would the approximate power consumption be?

Straight ahead or curves?

The electrohydraulic power steering sucks terribly - therefore, in the Vectra C, even the lights dim when you steer .

m;

matthiasTDI96 wrote:

How much electricity does the MSG consume? I'm just curious about how much electricity is needed when only the motor is running, with all comfort features turned off, meaning no radio, ventilation, or lights.

The MSG itself will consume relatively little electricity. The MSW/PDE (low-resistance pneumatic valves), the (PDE) pre-feed pump, and other components will collectively consume many times more electricity than the MSG.
"I'm also interested in this right now. I'm planning to disconnect the LIM (likely referring to a load management system) soon and feed power to the motor using a voltage-regulated battery charger: it provides about 9 amps at 14.3V. Let's see what the current meter shows..."

Quote:

So, roughly, ABS, MSG, and other control units like the airbag, and if present, the vehicle's electrical system, would need power. What would that amount to?

With the "ignition" on and the Polo engine running (including ABS, airbag, etc.), it draws approximately 5A from the aforementioned charger, if I recall correctly.

Quote:

"Ignition" on with the Polo engine running (including ABS, airbags, etc.) draws approximately 5A from the aforementioned charger, if I recall correctly.

My memory wasn't quite accurate; it's more like about 2 Amperes - after the priming pump turns off, which alone draws about 4 Amperes.

Quote:

I will soon disconnect the alternator and feed the motor with power using a voltage-regulated battery charger: this provides approximately 9 amps at 14.3 V. Let's see what the current meter shows.

During a previous attempt, the meter was already at its maximum. The on-board voltage in the low gear was about 13.3 V, which suggests a charger current of around 15 amps (as the total consumption of the motor, instrument cluster, on-board network control unit, ABS, airbag, without lights, and other power consumers).
So, approximately 0.2 kW is the minimum electrical power consumption of a PD-TDI passenger car under light load .

Well... and then all the extra stuff... not bad!

Hi,

In other words, this also means that you can drive for almost 5 hours with a fully charged 70 Ah battery, even if the alternator is broken (and you don't turn on any other electrical devices). This is, of course, assuming that the power consumption while driving is not significantly higher. However, it probably will be... the power steering and other systems will consume a considerable amount of power.

In that case, a VP-TDI engine with hydraulic power steering has a clear advantage.

Best regards,

Jan.

Jan6K wrote:

The power steering and the electric drive (PDE) will really drain the battery.

Yes, the steering system draws a lot of power; 10 amps in city driving is nothing. However, you can prevent this by removing the corresponding fuse (and, as a preparation for the then-necessary steering force, it's best to work out and become a bodybuilder).