You are right. And which brand ist them ? I found only 2,7V Supercaps…
Thanks
Thomas
You find them in the other thread…
Licap 18V 62F Ultracapacitors (SM0062-018-P-1)
Here:
no thats the same as the eaton supercap packs. but in the first picture its a single supercap mounted to the multiplus. i want to know which brand is them.
Kemet ALS70A334QS063
In the same thread, some posts above…
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Good morning,
The one under the inverter in this photo is the Kemet ALS70A274NT063 in this case, a 0,27F 63V electrolytic capacitor (black colour), not a supercapacitor.
The ones with the fuse in between is the Licap SM0062-018-P-1, 18V 62F (light green colour), that’s the supercap, placed in series, 36V 31F.
Be aware, that it must be minimum “calculated” to above mentioned formula to have proper effect.
Its not JBOC, just a bunch of capacitors…
For 24V systems, use 2x18V supercapacitors instead the 16V ones, as with lead acid the charge voltage can go to 32+V, for a single phase inverter use at least 50V capacitors (as are used inside the inverter as well), for 3 phase inverters use 63V as these get a combination of 100 and 300Hz and must work more, for the busbar capacitors (very very rare) use 40V capacitors and choke as there the voltage is more stable.
For Lithium 48V, use 3x18V supercapacitors in series, this as the charge voltage is below 54V, for the single phase inverters use 63 or 100V capacitors, for 3 phase preverable 100V but that is a very limited market and several more small ones must be placed.
For the amperage or F of these capacitors, I cannot say nothing before knowing as mentioned above, KWh, inverter power, load, ripple, etc, etc.
P.s. @ Thomas, can you delete pricing and where to buy it please, Victron moderators do not like that so much…
Regards.
Hi Jeroen,
why do you use “silver speaker cable” ? silver speaker cables are normally not silver but tinned copper wires.
Thanks. Thomas
Good evening Thomas,
Yes, indeed, each copper strand has a tin silver layer and there are more strands than a normal cable with way less resistance, making these cables super flexible and handle very high currents.
Also, they maintain their low resistance better as this layer also protects against corrosion of the copper.
Perfect for connecting capacitors, as these must “act” at the 100-300Hz range (1-3 phase), keeping ripple voltage low and start load currents high.
Car audio speaker cable will do perfect as well, and the ones for powering the car amplifier also if you need more amperage.
Regards, Jeroen.
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Good morning,
See the Kemet ALS70A754QT040, these ones we use often on a 24V busbar in combination with a choke (or multiple), CLC, for example the Vishay IHXL1500VZEBR68M5A.
Inverter power varying between 20-40KW in 3 phase systems.
This capacitor is heavy, so we always mount those with 2 clamps.
See the flat sides on the plus and minus connections, this is to put a small flat spanner to properly set torque to the wiring lugs, and so not to destroy the inside of the capacitor.
The choke can be soldered or clamped, we prefer to clamp those as that is easier and cannot damage the isolation due to the soldering heat, these chokes have automotive certification.
A single L in a single CLC combination of these will in general kill a ripple by half at maximum 200A, 5000W or 2 paralel Ls in a single CLC maximum 400A, 10000W 40% ripple improvement and 2 full CLCs 50-60% improvement at maximum 400A, 10000W.
Just to inform, due to the war with Russia the bigger capacitors are hard to get, as these are in the boycott agreements at the moment, so buying them from the States and import these to Europe is quite a paperwork to fill in, UPS helps the best from all transporters in that matter.
Regards, Jeroen.
Hi Jeroen,
in the datasheet of the capacitors is a lifetime of 20.000 hours defined. it seems very short.
20.000 hours = a little bit more than 2 years …
Thomas
That lifetime is defined for the maximum working temperature.
That it’s marked on the body and it’s usually 85 or 105 degrees Celsius. For the above mentioned capacitors is 85.
At normal temperatures, the lifetime is much more than that.
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Good morning,
Indeed Alex, an average quality electrolytic capacitor has a lifetime of 2000-5000 hours at 85C, these are build in the most electronic home appliances, these should last at least 10-15 years pending on mostly the frequency and the ripple current, as most home appliances are just made to last 10 years nowadays these are the most commonly used capacitors,
So, a capacitor with 20000 hours at 85C lifetime, is a high quality capacitor, these are mostly used for industrial machines, as these must handle way more “misuse” and are way better made inside.
One of the capacitors used in most inverters;
After applying rated voltage with specified ripple current of 3A for 5000 hours at 85C:
Capacitance change : ±20% of the initial measured value.
Same capacitor with slightly higher quality;
With a ripple of 5.4A for 2000 hours at 85C, capacitance change ±20% of the initial measured value.
You would say only 2000 hours, yes, but with a way higher ripple it can handle.
Same capacitor with industrial specs,
With a ripple of 8A for 20000 hours at 85C, capacitance change ±20% of the initial measured value.
An estimation is also given at 40°C.
Failure rate is frequently quoted in FIT (Failures In Time) where 1 FIT = 1 x 10-9 failures per hour.
At 85°C 220FIT, at 40°C 10FIT, meaning an industrial capacitor can easily handle 50 years of operational time.
Regards, Jeroen.
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Good morning,
Maybe this will help, Weblifecalc,
Here you can fill in the data of your capacitor, (this brand of this site only of course).
If you have another brand, then first look for one with about the same specs.
Then fill in on how the capacitor will be used, and voila.
My capacitors will run 484K hours, thats 55 years, not even my sons will throw these away…
Regards, Jeroen.
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