The capacitor is made by Ducati Energia in Italy. It is a type 4.16.27.19.

It is a polypropylene motor running capacitor.

See pages 15-21 in the Ducati Energia catalog (old).
https://www.rcscomponents.kiev.ua/datas ... _16_10.pdf

It is big because:
1. It is a safety component (it doesn't blow up or burn if abused - it vents).
2. It is meant for high usage cycle (e.g. coffee shop - not home)
3. It is rated for 10,000hrs

When looking for a cap, look for a polypropylene motor run capacitor. A regular capacitor rated for the voltage will probably also work in a home situation (duty cycle of a few times a day...).

You need motor rated capacitors, try a motor repair shop or maybe an appliance repair shop. I got the last one I purchased from shop catering to HVAC repair shops and air conditioning repair people.

Ira

I think this would do it:

30uF±5%, 500VAC, 50-60Hz, safety protection, "motor run capacitor"
www.mouser.com/ProductDetail/KEMET/C878AF35300AA0J
datasheet: http://www.mouser.com/ds/2/212/KEM_F306 ... 101634.pdf

It's only $9 but the shipping will double that price or more.
The one you linked has free shipping and so it's cheaper. It's probably okay too but looks sketchier somehow. I like to see datasheets.

Indeed that looks like a suitable replacement. It may actually be better as it is rated for 30,000 hours and not 10,000 hours.

Also check the size. Volumewise it will probably be similar - but they can be longer or fatter and may or may not fit within the grinder.

So I ended up getting this one http://www.sustainablesupply.com/Dayton ... 2-C1566025 . I guess the website is owned by Grainger because the package was shipped by them, arrived in 2 days from time of order. I plugged it into the grinder and it definitely seems livelier, so hopefully that works. Definitely better than paying the astounding markup the espresso Distributors were asking, imagine $80 for a $10 piece. Guess if people are willing to spend it though they have a right to charge it...
Thx everyone for your help!!! Much appreciated.
-Alan

It is a motor start and you need a motor run capacitor. Motor start capacitors are meant to be used only upon startup - and get disconnected when the Motor RPM goes up (usually due to a centrifugal switch disconnecting it).

However, that said, due to the low duty cycle of home use it may be safe enough to not blow up on you.

One point regarding pricing. When you pay 80$ for a 10$ part, you are actually paying for warehousing, sourcing, etc. They sell grinders, not capacitors. The ridiculous pricing is due to the need to keep a stock of very low velocity spare part.

Oh - and you have the wrong part. So now the price would double if you were to get the right part.

are you sure? I specifically bought a start (as opposed to a run) capacitor because that was what multiple people told me I needed - something that would give it a burst of energy to get started even though the beans pressing down on the burrs are causing friction and causing it to be harder for the burrs to start turning. Once they got that initial burst of energy and started turning, it was my understanding that the motor is powerful enough to keep the burrs grinding without needing a capacitor to keep things going. As I said, multiple people told me this. Were they incorrect? Please enlighten me. Others can feel free to chime in as well.

Justin shared a link to the 30μF capacitor for the Mazzer Super Jolly at Espresso Parts. They call it a start capacitor.

https://www.espressoparts.com/parts/esp ... -capacitor

Rocky

My electronics knowledge is mostly about tinier things and I'm just curious:

Could someone explain the key distinction(s) between a start capacitor and a run capacitor that both have identical capacitance, working voltage, and frequency? Does it have something to do with heat dissipation?

What I mean is, if you have a capacitor that doesn't have the word "start" or "run" printed on it, how would you know which it is?

The capacitor in your original picture is a run capacitor. It is a polypropylene capacitor in an fireproof electrolytic like aluminum enclosure.

It looks like an electrolytic but it isn't.

That is why I spent time finding and linking the data manual for the Ducati Energia capacitor.

As to what is the difference. Ideal Capacitors do not generate heat. That is because they store and release energy, and if operated on AC, the lag between voltage and current means the power dissipated is zero. (Real - not imaginary power).

But real capacitors have some D.C. Resistance. Called DCR. I and they heat up. Heat destroys electrolytics (start capacitors). Polypropylene Is less susceptible to heat.

Now both start and run capacitors create a fake pole that pulls the motor at a low high startup (and run) speeds. But start caps work only the first few revolutions and is disconnected when the motor slip is low enough for sustained run. Once disconnected, heat will be dissipated. Run motors are never disconnected and will continue to heat up.

Since grinders are on low duty cycle, I don't expect its life to be too short. So it may work...