Recharging batteries

[XenonSurf]

What's the fastest way to recharge batteries once they are down to about 50%? Going to surface and shut down all engines?
Will the recharge speed be dependant on how many engines are active, e.g. would it be faster if you go at slow speed rather than at standard speed? And only little recharge at full speed and no recharge at flank speed?



Thanks,
XS

[AP514]

Originally Posted by XenonSurf

What's the fastest way to recharge batteries once they are down to about 50%? Going to surface and shut down all engines?
Will the recharge speed be dependant on how many engines are active, e.g. would it be faster if you go at slow speed rather than at standard speed? And only little recharge at full speed and no recharge at flank speed?
XS

That is a good question..wondering that my self.
I was thinking the batteries would tend to get HOT at higher speeds due to the more Voltage being feed to them...
I personally recharge on speed 2, sometimes 3...just because the boat speed is reduced might as well save the Gas for when I can make good speeds.

[bstanko6]

In reality, slower speeds were better for a stronger charge.

In TWoS, If my battery is that low, I would shut down a diesel and then charge at slow speed.

Never stop moving forward! Even if you are moving at 2knots... keep moving!

[AP514]

hum how do you shut 1 engine down ?

[XenonSurf]

Originally Posted by AP514

hum how do you shut 1 engine down ?

You cannot do that directly, but you can set a specific speed, e.g. 8 knots, 9 etc. , and depending on the speed you set only x engines will be active (I imagine, I don't know), but you don't see this in the game, and the dials are not that precise, at some point my SH3 speed dial will change from full speed to medium speed if I set below 9 knots, if I then click on the dial it changes to show me the needle at the real speed. With SH5 dials you can do simmilar clicks to set the exact speed.
Underwater, the speed dials are incorrect, a side-effect of a sub-mod of TWoS according to the doc. If you klick Medium speed, the dial (and the sub?) will go at low speed etc. I think this is fixed somehow since 2.2.10 or before.


Also there is a fuel-optimal speed key command (SHIFT-M I think), I never tried this one, I usually patrol at 9 knots for best fuel consumption.



Thank you all very much for your inputs and advices!


XS

[Fifi]

Originally Posted by AP514

hum how do you shut 1 engine down ?

I think if you shut down one propeller, only one engine will run.
In TWOS you can shut down right/left propeller using the little round buttons down the telegraph bar

[Major Sunscreen]

I believe that is correct although the sim doesn't model the shutting down of one diesel visually from what Ive seen in game. With TWOS mod speaking to the Chief will give an option of using all available power for speed (from memory).

The following is quite an interesting read on the subject and the relevant section Ive copied and pasted just below although the pictures it refers to youll have to see in the article:
https://uboat.net/articles/id/54

Charging of submarine batteries:
The submarine batteries must be charged from a source of DC (direct current). Voltage of the DC source must be higher than voltage of the batteries. Terminals of the source and the battery must be connected on the following way: "plus" with "plus" and "minus" with "minus". The charging of the submarine batteries must be as fast as possible. It depends about the cell technology and about the method of charging. The most efficacious method is "UI-method". The method begins with high electric currents, until to cell voltage of 2.4 V, i.e. up to beginning of gas. After that the charging continues with constant voltage and reduction of the electric current. A battery is full charged when the battery voltage and the electrolyte density are constant for a longer period.
The DC source is (the most often) a DC electric machine. The same DC electric machine works as a DC generator and as a DC electric machine for submarine propulsion. The DC electric machines/generators and additional apparatus for the battery charging are located outside of the battery room. When the submarine is surfaced the electric machine is powered by a diesel engine and works as a DC generator and produces DC current for the batteries charging.
Picture 1 shows situation when a submarine is surfaced. DC generators/electric machines (EM/G) are powered by diesel engines (DE). One part of produced electric power from the DC generators/electric machines is used for propulsion of the submarine propellers (P) and the rest of produced DC electric power is used for battery (B) charging. In this situation the diesel engines are full loaded. When the submarine's speed is faster the time of the battery charging is longer, because fast speed needs more electric power. Opposite, when the submarine's speed is slower the time for the battery charging is shorter. In that case, slower speed needs a smaller part of the electric power and the bigger part of the electric power remains for the battery charging.

When the submarine is under surface the diesel engine cannot operate (except in some cases). Then the DC electric machine (powered from the batteries) works as the submarine propulsion engine.
Picture 2 shows situation when a submarine is under surface. The submarine's diesel engines (DE) are out of work. DC electric machines (EM) are powered from the submarine's battery (B). In this case the DC machine/generator works just as DC electric machine, because there is no any production of the DC electric power.