Please read the textbox/description first. I wanted to show that a gearbox of a (to be discarded…) analog time clock could be re-used for other purposes.
But it failed and the clock motor coil even burned out during the video. I had not expected that at all.
Reason/fact: a 4800 Ohm DC resistance of a normal transformer coil made for 230 Volt at 50 Hertz can (normally) never burn out due to heat, even when its output winding (secondary, say 5 to 20 DC Ohms or higher) is shortcut.
Thus in case of a transformer (!) circuit with a steel/laminated core and that 4800 Ohm (DC measured) winding on the primary winding at say 230 V at 50 Hertz or 60 Hertz: it is no problem.
BUT: This is not a transformer circuit (!). The way that the core of this clock/gear unit/motor is/was made has in fact not a serious steel/laminated core.
The only back-inductance effect making that the electric motor moves is tiny, due to the more or less absence of steel/iron in the motor that drives the gearbox.
Thus the 4800 Ohm DC/AC coil “sees” no (or not much) back-resistance (inductance) when the time ring or time gears in the gearbox are stuck and the coil (thus) gets extremely hot and burns out. Showed in the video.
In general: this is a serious problem when we use these analog cheap Chinese made time clocks.
In more critical situations (when the movement ring/gears gets stuck) the motor will burn out via the motor supply coil, plastics will start to melt when the motor movement gets stuck.
There is in general a protective resistor to prevent fire, etc, going to the motor coil. Though the motor of the clock can burn out/melt when the motor gets stuck. The resistor could (can, will) prevent more damage and even fire.
Please note: I removed a (that) resistor in this demo, these resistors could go to the coil-winding of the motor, to the 4800 Ohm (DC) winding, thus limiting the maximum current through the motor winding, anyway.
Anyway: a healthy 4700 Ohm (measured via DC measurement) coil wound on a proper laminated steel core (with the standard isolated steel platelets) normally (!) cannot burn out on 230 Volt at 50 Hertz, its inductance is too high (in that case) to produce that effect. Calculate e.g. its AC resistance.
So we have to do with a peculiar effect in case of these Chinese analog time clocks, that produces quite some or even say a destructive heat when the time-ring or the motor gets stuck.
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I keep all my YT videos constant actual, so the original video’s with the most recent information are always on YouTube. Search there, and avoid my circuits that are republished, re-arranged, re-edited on other websites, giving not probable re-wiring, etc. Some persons try to find gold via my circuits. I take distance from all these fake claims. I cannot help that these things happen. Upload 22 May 2022.