Hello again! I am trying to learn the basics... What are these and why are they there? (Husqvarna 21E)
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Hallo nochmal! Ich versuche, die Grundlagen zu lernen... Was sind diese und warum sind sie da? (Husqvarna 21E)
Grüße -Ilari
Du hast keine ausreichende Berechtigung, um die Dateianhänge dieses Beitrags anzusehen.
these look like chokes for noise-suppressing (in connection with the capacitor shown).
The experts-in-residence for electronics are Klaus and Detlef, btw.
regards, Helmut
Zuletzt geändert von Hosenkürzer am Donnerstag 21. Januar 2016, 00:03, insgesamt 3-mal geändert.
@Helmut
Sorry, unsere Nachrichten haben sich zweimal überschnitten.
Was Du geschrieben hast ist richtig
@Ilary
Helmut is right.
These inductors are just made of copper wire. They will never go defective.
The two long bare wires to the capacitor I find a little strange.
I guess somebody changed already the capacitor.
The wires should have a sleve for isolating.
The capacitor looks new. These type of capacitor will propably never go defective.
Thank you for your answers! I am sure the capacitor has been changed sometimes to new. There is nothing wrong with the foot pedal. I am just curious about how the devices function. I have a small collection of machines and I would like to know them completely.
But what is the purpose of these inductors? Is it to discharge the capacitor after switch off the power? Or is the purpose to change the current somehow. I have not seen these anywhere else. Or does the Pfaff 360 foot pedal have one of these as well (a copper coil)?
Regards -Ilari
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Vielen Dank für eure Antworten! Ich bin sicher, der Kondensator manchmal neue geändert. Es ist nichts falsch mit dem Fußpedal. Ich bin nur neugierig, wie die Geräte funktionieren. Ich habe eine kleine Sammlung von Maschinen, und ich möchte, um sie vollständig kennen.
Aber was ist der Zweck dieser Induktoren? Ist es, um den Kondensator nach dem Ausschalten der Strom entladen? Oder ist der Zweck, um die aktuelle irgendwie ändern. Ich habe nicht diese gesehen anderswo. Oder hat die Pfaff 360 Fußpedal haben eins von diesen als auch (eine Kupferspule)?
The inductors are intended to reject very high Frequency RFI (Radio Frequency Interference).
What we call UKW (FM-Radio) and VHF (Television). Both came up in the 50th. In older Devices You only find capacitors with can compress the lower Radio frequency Interference Long Wave, Medium Wave and the lower Shortwave but not Frequencies, lets say above 3 Mhz. FM- Radio and TV was not jet present.
In Germany we call those Inductors "UKW-Drossel" because of its purpose. They often exist just of a ferrite core und 2 - 4 turns of copper.
You can simply ignore them, They normally never go defective.
As a very simplified, shortened Explanation:
A capacitor makes a short for High Frequencies while they are completely open at low frequencies or DC.
A Inductor makes a high resistance at high frequencies while a complete short at low frequencies or DC.
Thats the reason capacitors are wired in parallel to the interference source (Motor) and the inductors are wired in series to the Interference source so they get not conducted.
Klaus, thank You for a very good explenation. I don´t remember I had seen inductors in any other foot pedal. So both capacitors and inductors are just for the radio frequency interference purpose.
If I have understood the basics correctly, the capacitors in the foot pedal can be removed whithout any harm to the machine itself but the motor capacitor also protects commutator and brushes (reduces sparking) allthough the machine seems to run fine without any capacitors?
The radio frequency interference itself is another story...