at last! my E57

[orestis]

HI!

Deutschland is the country with the bigger siren supply! In Greece it is impossible to find a siren to buy. The state only manages this stuff and when the sirens go down nobody knows where they go!

So, thanks to Deutschland I have now such a siren

But unfortunatelly the name plate got lost and no data... The man who sold it to me, told me it’ s probably an Elektror of 1980. I suppose it must be older, what do you think?

Greetings
Orestis

[Der Matze]

Congratulations! It looks really nice!
But where did you get an in that good conditions? I think it has been restored, is it?

look at the three parts that support the rotor on the motor. I think they are not the typical of E 57. Are they?

I would say yours looks the same as both of mine...

[orestis]

Thank you, Der Matze!

Yes, the siren was restored... But it will be restored again!
I have a relative in Germany and he found a seller... and that's it.

But the supporting parts I think in the most are strait - shaped. But in mine it gets thicker when it comes to the rotor's edge... That reminds me the old Elektror L141

By the way I'm waiting you to restore your sirens!

[Siggi]

I think it's a normal .

The foot looks usually. I can't see special differences.

In fact it is a nice siren and have lots of fun with it!

[orestis]

!

I wonder if I can connect it to power... That would be difficult...

[Wolfi]

Hi orestis !

What`s difficult in connecting the siren to the power ?

Don`t you have in Greece the same mains voltage / frequency
like in Germany and most all over in Europe ...

230 / 400 volts 50 Hz ?

Greetings and have fun with your ,

Wolfi

[orestis]

Hi Wolfi

Yes, but an electrician told me that in the house current, it is really difficult, because I mast connect it directly to the central switchboard, to add some fuses etc... and when he saw "D/l 15,5/9.0 A" he said "do you insist? It's almost impossible!"

Well, I don't know much about electrology...

[Wolfi]

Hi Orestis !

The siren needs a three phase AC power supply, so you must connect
the siren motor in "star" mode (Y 400 V) to the three phases of the
house installation. In every phase, a time-lag (delay acting) fuse of
at least 16 A rating is required.

Normal household fuses, even when rated at 16 amperes, in most cases
are too fast in action, and will blow immediately after powering on, due
to the high initial starting current of the 5 kW siren motor, which is 35 A
approximately.

Be sure that the metal wiring jumpers in the connecting box of the motor
are connected in "star" mode. If you are in doubt, please load up a photo
of the opened connecting box, and so I can tell you if your motor is
connected in "star" or in "triangle" mode.
In triangle mode, it is only permissible to connect the siren to a 230 V
mains voltage, not to 400 V !

And, very important to say: please be VERY careful in use of power
electricity! 230 volts AC are very, 400 volts EXTREMELY dangerous !!!
If you aren`t sure in handling of electric circuits, please don`t do it
yourself, but ask an electrician for support.

Have fun and good luck ...
Wolfi

[orestis]

@Wolfi
Thank you very much for your tips!

Of course I will call an electrician to be sure everything is done correctly...
I wouldn' t dare to try to connect the siren on my own!

But, just to have an idea, I think I need a special switchbox for the motor, is that correct? And I think the delay acting fuses are the old round ones, aren' t they?

[Siggi]

Yes, that's right! You need a contactor to shut all phases at the same time.

The old fuses are ok, but it is better to use new fuses.

By the way, the motor is connected in Y-mode ("Star") at the moment!

[Wolfi]

Hi Orestis !

Thank you for your excellent photo !
Yes, indeed ... there is no doubt, your siren is connected in star mode
and so ready for operation on the 400 V 50 Hz three phase AC line.

Both types of fuses, quick-acting (fast) and delay-acting (slow), are
available both in an one-way melting-wire form (round in most cases,
that`s it what you mean) and as magnetic, reversible "circuit-breakers".
If you choose the "round" type of fuses, you must have a look on its
characterization, if it is marked as a fast acting or a slow acting (time lag)
fuse. Magnetic circuit breakers are available in single-phase types
(usually like the fuses installed in your household installation), or as
double or triple block, which can be used in three phase power supplies.

Characterization is classified usually as letters here in Germany.
"B" or "L" types are quick acting, "C" or "K" indicates a time-lag
characteristic. This is necessary especially in motor circuits, to
withstand the initial starting current which is normally 4 to 8times
higher than the rated current, in case of induction motors.

But ... for making a little experience there is an easier way to let
your siren a little rotate. "A little" is true - yes, not with full power,
better for your ears and for your neighbourhood ... and with
no danger of high voltage electricity.
Principally, it is possible to operate a three phase induction motor
from a single phase supply. But, this is NOT recommended under
rated voltage, power and load conditions, due to risk of overloading
the motor`s winding. But only for testing and making some rpms,
simply take a low voltage AC 50 Hz source of about 20 to 40 volts -
so, a low voltage safety tranformer - and connect the secondary
to two of the three motor terminals (unimportant, whichof them).
Please check the flowing current (it should be < 9 amperes),
and then: Give the rotor a little "kick" in the direction it shall rotate
(three phase motors are not able to start with one or two phases
connected!). I think, it will continue rotating properly ... of course
at only a little rotation speed compared with the rated 2800 rpm.

Best regards and have fun,

Wolfi

[orestis]

@Siggi, Thanks for your tips! And you 've done very good job in building your own contactor!

@Wolfi, extremely interesting and professional tips! Thank you very much! I' ll do my best, I hope that is going to work...

[orestis]

I started yesterday deviding the siren parts... the rotor bolt didn' t want to be unscrewed!

[orestis]

And the motor... It's shaft is in perfect condition. I wonder if I have to remove the runner to check if it is rusty.

[HP.D]

well, usually you don´t have too, but of course you can. The bearing looks quite rusty, too... Perhaps you should buy a new one.