Range of speed of XXI Type

[pedro gomez]

I'm interested in know what was the maximum and minimum speed of the electric motors in XXI type.
Someone can help me?

[JWLaRue]

Hi Pedro,

I've seen various numbers

Hi Pedro,

I've seen various numbers for the maximum speed of a Type XXI, but the numbers typically are in the 17.2 - 17.5 knots range.

As for the minimum speed, that would be zero. But seriously, are you asking what the minimum creep speed is? That would depend on how well trimmed the sub is the better the trim the slower the speed.

-Jeff

[pedro gomez]

speed electric engine

Yes, my question is what was the max and min speed in rpm of the XXI's electric engines.

[hakkikt]

Hi Pedro!
This is a translation

Hi Pedro!
This is a translation from the German Wikipedia article
(http://de.wikipedia.org/wiki/U-Boot-Klasse_XXI). Notes in [] are by me.


Main electric motors] In parallel connection, the maximum output of a "Hertha" [that is the name of the electric motor unit] was 1840 kW at a current consumption of 5500 kW and a speed of 1657 rpm at 360 V. In serial connection, the motor produced 730 kW at 1230 rpm. When used as a generator, 1840 kW were produced in parallel connection and 1040 kW in serial connection, both at 1550 rpm and 450 V. Gearing was at 6.77] They could be fed 120 V at 74-245 A current consumption and 7.6-22 kW output, or 360 V at 140-256 A current consumption and 46-83 kW. Due to the power gap, speeds between 4.3 and 5 kn were difficult to reach.

In a submerged one-mile trip, U 3506 reached 6.1 kn at a silent propeller speed of 122 rpm.

The creeping motors were connected with the shaft via twelve v-belts and a friction clutch at gear reduction of 2.68:1.

[from which I would deduce a creep motor speed of 2.68*122 = 327 rpm]


-Harald

[pedro gomez]

Electric XXI engines

Thanks Harald
That is I wanted to know
I'm trying to adjust my XXI engines to real engine speeds.

Pedro

[JWLaRue]

Pedro,

I'm curious as to why

Pedro,

I'm curious as to why knowing the actual speed of the e-motors helps you to adjust your model?

Wouldn't the actual speed of the boat be what you need?

-tnx,

Jeff