LED Capacitance nF table - put your values here.

I wanted to encourage the members to share what information they have about LED lamps and their nF capacitance. Please add your information so that we can have a lookup table.

I will edit this post and keep adding values as I find them.


Brand and model ------------------------------------------ Capacitance nF

Brightgreen D900/D1000 - 16W ------------------------------- 47nF

Clipsal 16w L960 or L935 ------------------------------------- 10nF

Pierlite Starburst - 16W -------------------------------------- 47nF

Pierlite Starburst Eco - 11W ---------------------------------- 47nF

Pierlite Starburst Pro - 18W----------------------------------- 47nF

Osram Parathom Pro Par16 50 Advanced 10W GU10 ------------ 22nF

OSRAM Parathom Pro 10W PAR16 is 27nF in some cases. OSRAM factory statement is 22nF.

EVO 50 from LED lighting ------------------------------------- 47nF

NOTE: Advertised power rating and actual consumption differ on almost all lamps.



http://updates.clipsal.com/ClipsalOnline/Files/Brochures/W0000412.pdf

 

Clipsal 12w L960*/L935*.. Was told 80pF by their lighting tech, believe its more likely 80nF, am going try to test tonight.. Will update accordingly..

 

Updated

 

Updated

 

Great thanks tobex.

What about the LED Lighting EVO?

 

EVO is 47nF.

 

Thanks.

I've come across the chart of transformers listing their capacitance:
http://updates.clipsal.com/ClipsalOnline/Files/Brochures/W0000412.pdf

It says at the bottom "L5508D1A when used in conjunction with a 32EIND ( 400V.A. rating, approx retail listed price $37.50 in 2004 ) may allow the individual channel to be fully loaded to 240 V.A. regardless of the transformer capacitance. However, 1 x 32EIND would be required for EACH CHANNEL that exceeds 300nF capacitance."

Can this be used with LED lights? Has anyone tried/tested this? This device would be well worth the current trade price of $44.83 (saving a channel, cable, board space, time etc).

 

mixed inductance results

Hi Memphix
I used a 32EIND about 7 years ago, with Electronic Tx & Halogen lamps. The Tx were Vosloh Schwabe, chosen for their low capacitance from memory, with philips dichoric lamps. The most I had on one channel was 4 x 105Va Tx with 2 x 50W lamps on each. The problem was that after being on for a while they would start to flast, disco style. I could not work out what the issue was, swapped channels etc. Tried installing the 32EIND and it apparently helped but did not eliminate the issue.
Bear in mind that I did not see the issue when I went to the house, only had the occupant reports. I think the dimmer got replaced and that fixed it eventually.

Anyway back to the point, the 32EIND are the size of a large clipsal J-Box so you do need space to mount them, also from memory only the active goes through them so you don't want them too far away from the dimmers.

I think I still have one in the shed, will go have a look.

Cheers
Matthew

 

Thanks Matthew.

Could mount them else where if you use SDI as the switch wire from the channels I guess, but typically not how I wire it.

I'd really like to know why each channel requires it, not just each supply?

Anyone tried it with LEDs?

How much capacitance can the 2 amp dimmers handle (L5504D2A) and universal dimmer?

 

The 32EIND affects the way the current flows through the dimmer channel, hence the need for a 32EIND per channel. Connecting the 32EIND to the dimmer supply may affect things like the ability of the power supply to power the channels or the correct detection of the mains zero crossing (which is necessary for the correct timing of the triac firing).

The L5508D1A and L5504D2A leading edge dimmers both have the same channel capacitance limit of 300nF per channel. Leading edge dimming and electronic load types are always going to be a mixed bag of compatibility. This is because the capacitive load results in a huge in-rush of current when the dimmer channel turns on. This large current spike can do all manner of damage/stress to the electronics, not to mention the radiated EMI. There is almost always a rinigng current associated with this large current spike. If the LED driver is designed to handle it, it should be OK. If not, then things will get damaged.

The 32EIND, being an inductor, can help in that it can limit the peak current that occurs during this time of large inrush current when the triac first turns on. This in turn can reduce the magnitude of the subsequent current oscillation through the dimmer channel in the microseconds that follow. If this ringing current is reduced sufficiently then the triac may continue to conduct rather than dropping out. It's still not an ideal situation, but for some situations and types of loads the 32EIND can be enough to stabilise the dimmer channel.

It's also worth pointing out that just because the light output is stable does not mean that the dimmer channel is operating properly as some of this can be occurring in the background and, due to the design of the particular load, the light output may not reveal exactly what's going on.

There is no capacitance limit for the L5504D2U universal dimmer as it will run electronic/capacitive load types in trailing edge mode automatically.

 

Great info thanks.

Just to make sure...

If the universal dimmer is set to leading edge (pretty sure thats an option from memory) it is 300nF also?

What about the professional dimmer, capacitance rating?

No reason why the 32EIND would not work well with LEDs?

 

The DIN Universal Dimmer auto detects the load type and runs in the correct mode. There is no option to override this behaviour.

The Professional dimmers (purple anodized ones) have a channel capacitance limit of 1000nF.

The Infinity Professional dimmers have Leading Edge dimmer cards only and I don't think Clipsal have published a channel capacitance limit. There is some extra cleverness going on in the Pro Plus leading edge cards that make them more tolerant of electronic-type loads.

The Infinity Architectural dimmers have Universal dimmer cards. They also have the ability to be manually set to leading, trailing or auto dimming modes.

Will the 32EIND be a silver bullet that solves all the problems? No.
Will the 32EIND allow you to dim a LED light that was not designed to be dimmable? No.
May it help under some circumstances when epxperiencing compatibility issues? Yes.
Are you better off using a LED light that was designed for use with both leading and trailing phase control dimming from the start? Absolutely.

 

Great!

DIN universal dimmer: if auto detects leading edge, what is the capacitance? I'm expecting 300nF.

Anyone know of transformers for halogens that would be trailing edge?

 

The universal dimmer will only run in Leading Edge mode if it detects an inductive load, such as an iron core halogen transformer, where the dominant component of the load reactance is inductive. In all other cases the DIN Universal Dimmer runs in trailing edge mode. If you presented a load to the Universal Dimmer and it had 300nF of capacitance it would dim that load using trailing edge dimming.

Just about any electronic transformer for halogen down lights that is dimmable will prefer to be driven with trailing edge dimming, and this is what the DIN Universal dimmer will do when it sees that load type.

 

I've come across a lighting shop who claimed to have C-Bus compatible LED downlights. And they are correct from what I can see, but only on a universal dimmer - they thought it would be fine on a standard dimmer however.

These downlights were tested for the capacitance rating at my request and recorded a 2.17mF... 2170000nF! Surprised at this result. Apparently there are several electricians out there putting these on standard dimmers. What is the likely outcome on the dimmer?

 

Bump... are people worried about the capacitance of these LEDs