Dimmer Burning & General Question

[JoshGreenUK 0]

Hi,

 

I have some Fibaro 2 Dimmers, I am greatly concerned about them burning and catching on fire, I see there are some reports on the forums of this mainly from Dimmer 1 but also a couple on Dimmer 2. Not really sure what I am asking but because of the reports its enough to make me reconsider Fibaro equiptment as it will be nested in timber walls and timber floors.

 

EDIT: In the Dimmer 2 burning posts, there are next to no replies which also doesn't fill me with confidence of Fibaro's response. My main concern is why the over temp sensor didnt kill power before it was melted.

 

Additionally, I have Load error on 2 of the 3 dimmers I have setup, all are the same lights but the 2 with load error have 12 and 10 spotlights (Philips 6.3W Master Dimmable) each. Cannot work out what the problem is here and coupled with the above, greatly concerning. The lights seem to independently switch between dim levels at low dim, this is also really frustrating and didn't happen with Varilight V-Pro dimmer, so wondering what could be causing this?

Edited December 19, 2022 by JoshGreenUK

[Tim__ 96]

Hi Josh, you've asked a few questions, let me have a crack at answering. I've had 20 Dimmer2s for a couple of years, and while they do get slightly warm as you'd expect, never anywhere near enough to catch fire. I guess it's possible to happen, but so is mis-wiring which can cause the same.

 

I sometimes get load errors as well. Especially on low power LED lights. The error is telling you that the power consumption is very low and a bulb may have burnt out. As everything seems fine, I just ignore them now. You can change parameters to help avoid them:

 

"Dimmer 2 is equipped with functionality of detecting the burnt out bulb. In case of such situation, Dimmer 2 sends the notification about load failure. Described function is not available for values of parameter 58 different than 0.

Power variation is detected in accordance with the settings of parameters 15 and 16.

Example:

Parameter 15 set to 30%.

Parameter 16 set to 5 seconds.

Dimmer 2 will detect the change of load at the moment of power variation by 30% compared to standard power consumption (measured during the calibration) and after 5 seconds from brightness level stabilization.

This function is available only in a control mode compliant with the mode recognized during the calibration (parameter 14 set to 1)."

 

The small change in brightness at low levels can be caused by power supply voltage fluctuations, or less than perfect drivers in the LED bulbs.

 

Load errors and brightness changes can be reduced by using bypasses and ensuring you use the 3 wire connection method.

 

The Dimmer2 seems to be recognised as having quality construction and functionality, compared to other brands. Notwithstanding a few quirks.

 

Hope this helps!

[JoshGreenUK 0]

Hey Tim,

 

Thanks for the response! So as I am dipping my toes in here I feel like before going and changing all 40+ GU10 lights I should look a bit further first just in case its something that can configured. This is where I found the burning posts etc, putting that aside I can make them less risk of doing damage by better placing the dimmers, I see there are some DIN module mounts for them which would work very well.

 

Anyway, more to the 'bouncing' issue, I ordered a Aeotec Nano Dimmer and went ahead and set that to the lowest dim level, it is considerably dimmer than Fibaro and no bouncing of dim levels. I have stepped up the min dim level step by step to try to replicate the bouncing issue and it is nowhere to be seen. Unfortunately only Fibaro support the switch configuration I have and therefore I am looking back at Fibaro. I really need to sort out the bouncing issue, the Aeotec was wired with 0 bypass's. Right now as we speak the Aeotec is at its lowest dim point and currently wired in, it is reporting a consumption of 15.73w (12 drivers). Perhaps the Fibaro isn't able to go as low as what I am expecting it to.

 

What drivers do you use? I am using GU10 Philips Master Dimmable 6.2w 575lm 240V

 

Good to know about the load issue, however it doesn't fill me totally with confidence as I would expect less drivers to cause this issue, with 4 drivers it is no issue but with 10 or 12 drivers it is an issue.

 

Some specs from the Aeotec:

Max 100% = 82.53w

50% = 43.12w

1% = 15.73w
 

I saw some posts about adding a secondary bypass module, my dimmers are all wired with neutral so didn't think they were needed at all (but did try one to try to mitigate)

[Tim__ 96]

I use the haseman DIN rail mounts in the new part of our house. They work well and are easy to wire, just make sure the aerials are straight inside the enclosure.    

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Be careful if you buy the package that includes the Dimmer2 device - it will be the EU frequency version.

 

I have a variety of drivers: LED bulbs (these cause me the issues), LED downlights (OSRAM LEDVANCE Superstar Downlight 7.5W 240V Tri Colour 3K/4K/5K 92mmØ Dimmable), custom LED fittings.

 

That's interesting about trying a second bypass, hadn't thought of that...

 

This post provides a little more background, and suggests some parameters to check:

 

[JoshGreenUK 0]

Is what I am describing about them bouncing them dim levels considered flickering? They don’t go off at all just gently bounce like the voltage is fluctuating….

[petergebruers 1,231]

42 minutes ago, JoshGreenUK said:

Is what I am describing about them bouncing them dim levels considered flickering? They don’t go off at all just gently bounce like the voltage is fluctuating….

If you want "rock solid" lighting then your only option is lights based on DC, like RGB(W) strips or "smart bulbs". I have been on this forum for a while and I have not found an AC + Dimmer + Lamp combination that stays 100% stable. I think one of the factors is the addition of solar converters to the grid, and more "nasty" loads like LED lamps which cause the grid voltage to deviate more and more from the ideal sine wave. AC dimmers do not "regulate" the amount of power, they merely assume that when you cut of 50% of that "sinoid" you get a somewhat stable 50% output.

 

You can try one setting though and I cannot predict which one works best for you.

 

Parameter 30: Load control mode

0 - forced leading edge control

1 - forced trailing edge control

 

I get better results with my 10 year old Philips Warm Glow when I force it to 0 - leading edge

 

A parameter was added in later firmware versions of "Dimmer 2" to handle a specific kind of flicker, one that exists in countries that add pulses to the power grid to signal night tariff or turn on street lights. I have not tested this parameter because Belgium phased out that type of communication protocol.

 

11 hours ago, JoshGreenUK said:

I saw some posts about adding a secondary bypass module, my dimmers are all wired with neutral so didn't think they were needed at all (but did try one to try to mitigate)

Adding two bypasses to one dimmer does not make sense. Maybe the confusion arose from the different types of bypass, there are 2. Dimmer 2 only works with "Bypass 2 (two)". And Dimmer 1 only works with bypass 1 (one). They are different parts with different part numbers. You want FGB-002!

 

The manual says:

 

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supported dimmable light sources (power factor > 0.5) with minimal power of 5VA using FIBARO Bypass 2 (depending on the type of load)

 

That leaves some room for interpretation.

 

As a rule of thumb, in 3-wire setup, if the light stays on when dimmer is off then you need a bypass

 

I would say it does not happen very often if the total LED load is > 25 W per dimmer but some bulb types are prone to "ghosting"