Jump to content

Welcome to Smart Home Forum by FIBARO

Dear Guest,

 

as you can notice parts of Smart Home Forum by FIBARO is not available for you. You have to register in order to view all content and post in our community. Don't worry! Registration is a simple free process that requires minimal information for you to sign up. Become a part of of Smart Home Forum by FIBARO by creating an account.

 

As a member you can:

  •     Start new topics and reply to others
  •     Follow topics and users to get email updates
  •     Get your own profile page and make new friends
  •     Send personal messages
  •     ... and learn a lot about our system!

 

Regards,

Smart Home Forum by FIBARO Team


  • 0

Switch 2x1,5kW stuck (welded) because of 20W LED driver


petergebruers

Question

Yesterday, one of my FGS221 Switch 2x1,5kW got stuck in the ON position. I immediately suspected the 20W LED floodlight connected to it. I had used this floodlight on my desk and I noticed at the time... that closing the contact to the supply of this light could give some really nice pyrotechnics. I think the driver does not have an inrush current limiter, or it uses a bad one. It is built and designed in a very big country, and I did not find specifications of this unit.

So, yesterday I had to remove my toggle switches, then gently knock five times on the Fibaro module behind it and it got unstuck... The switch seems to be OK, I left it in service.

But now... for a solution. The first thing I had in mind was a 10 - 60 ohms NTC in series of this driver. But I didn't have any at hand. So I thought... 20W is not a big deal... Why not put a 15 ohm resistor 1/2 Watt in series? Then I tried the floodlight on my desk: when closing the circuit the arcing was a lot less. I own 4 of these and I have now modified them all.

Please feel free to share you opinion on this!

Link to comment
Share on other sites

Recommended Posts

  • 0
  • Inquirer
  • 7 minutes ago, Bodyart said:

    @petergebruers,

     

    woul'd a simple NTC be suitable to limit the inrush current?

     

    Yes, what kind of load?

    Also, see my previous posts:

     

     

     

    Link to comment
    Share on other sites

    • 0
  • Inquirer
  • 10 minutes ago, jakub.jezek said:

    I recommend to customers or dealers contactors, if they can use it.

     

    Sorry that links are in CZ:

    Contactor:

    Please login or register to see this link.

    manual (should be multi lang):

    Please login or register to see this link.

     

    Thanks for sharing. I see the SMR-B is specified for motors, compensated and uncompensated fluorescent lamps up to 690 VA. That's a pretty good spec (because these are tough loads)...

    Link to comment
    Share on other sites

    • 0

    Do you have any conclusions about the load? I am from China and I am deeply troubled by our manufacture. 2X1.5kw can not be used. I don't think the relay is a very good solution. Is there any other solution?

    Link to comment
    Share on other sites

    • 0

    I have the same problem with 4 relays x2 out of 12 stick after 3 months of operation. In all cases only one channel is faulty though both channels serve approximately the same load LEDs. Unfortunately this is quality problem and twicks will not help

    Link to comment
    Share on other sites

    • 0

    Peter put me on to this post which didnt come up in my search.

    Before I read any of this I came to the same conclusion and was shocked by the poor inrush protection in some switched mode power supplies.

     

    We could blame Fibaro but overall I think they make great quality products, even if the support model is sometimes frustrating.

    Do we want theses modules to be twice the price and larger in order to suppress inrush currents of e.g. 100A for 1-2 ms?

    If some enhancements can be made then great, but its not always simple.

     

    Personally, I'm going to just avoid any cheap/small/poor quality switched mode power supplies.

     

    10 minutes ago, earto said:

    I just had the same issue with the 2nd channel of my FGS-223 being stuck on after months of no problems switching my 9W LED stair lights.

    I tried power cycling the unit and messing with settings including a re-initialise.

    Finally out of desperation, a sharp tap on the back of the unit released the relay.

     

    Initially, I didnt think the in-rush current for these LED lights would be a factor but now I'm not so sure.

    There's only 3x 3W LED lights, each one has its own small driver.

    After some research, it appears that smaller/cheaper drivers (switched mode power supplies) lack the inrush protection of higher quality drivers.

    One article suggests that the inrush current of smaller drivers is typically 40-70A for 1-2 ms (at the worst time/highest point in the phase)!

    Yep, that would do it!

    Please login or register to see this link.

    Time 5 milliseconds/division. Peak inrush is just more than 50amps for around 1.5milliseconds.
    Blue - mains 100V/division:
    Peak Yellow - input current 20amps/division

    My LED stair lights were already in our house and look like first generation LED lights.

    I could make a circuit to limit inrush current but I'll probably just replace them with better units.

     

    In conclusion, be wary of cheap/small drivers for LED lights - especially multiple in the same circuit.

    Please login or register to see this link.

     

    Link to comment
    Share on other sites

    • 0

    I have a number of power outlets which are controller from a central place by way of relays.
    To make sure, there is problem whatever you plug in, I have Finder relays which are controlled by ZWave relays.
    The Finder relays are really very good and never get stuck.
    Maybe a bit overkill, but just to be sure....

    Link to comment
    Share on other sites

    • 0
  • Inquirer
  • 7 minutes ago, Willem-Jan said:

    I have a number of power outlets which are controller from a central place by way of relays.
    To make sure, there is problem whatever you plug in, I have Finder relays which are controlled by ZWave relays.
    The Finder relays are really very good and never get stuck.
    Maybe a bit overkill, but just to be sure....

     

    I fully recommend your solution. It is not overkill, I recommend some further reading below to find out why.

     

    Just be careful when ordering one. Please read the datasheet. They have a truckload of models, so double check the partnumber!

     

    Also, their smallest version is still as big as a Fibaro module and requires soldering skills... If you want screw terminals or sockets, that's possible to but makes them a lot bigger.

     

    There is a picture of such a relay and some other (for instance, the FGS relay and an SSR)  in this post:

     

     

    In fact, when you mention "outlet" and 'overkill" you might be interested in the complete topic. It deals with power ratings, difficult loads like motors and so on:

     

     

     

     

    Link to comment
    Share on other sites

    • 0

    I have Finder 22.21.8.230.4000 (max 20A load on 230V).

    I already have them for years and I never had a problem of one getting stuck.

    Link to comment
    Share on other sites

    • 0

    The topic has been moved from "

    Please login or register to see this link.

    " to "

    Please login or register to see this link.

    ".

     

    Temat został przeniesiony z "

    Please login or register to see this link.

    " do "

    Please login or register to see this link.

    ".

    Link to comment
    Share on other sites

    • 0
  • Inquirer
  • With 4.160 Fibaro released a FW update for FGS-2x3 aka "Switch 2" which should improve handling of inrush current (for capacitive and resistive loads, inductive loads are a no-no).

     

    The release notes mention "switching at zero crossing to reduce possibility of welding of the contacts."

     

    The proof of the pudding is in the eating, but it sounds good ;-)

     

     

     

     

     

     

    Link to comment
    Share on other sites

    • 0

    Hi all,

    has someone verified the effectiveness of the FW upgrade regarding the contact welding issue?

    Is still necessary to apply some current limiting techniques for LED loads?

    Link to comment
    Share on other sites

    • 0
    On 5/17/2018 at 6:17 PM, GzOnE said:

    Hi all,

    has someone verified the effectiveness of the FW upgrade regarding the contact welding issue?

    Is still necessary to apply some current limiting techniques for LED loads?

     

    I quote myself.

     

    I've got a brand new Double Relay, upgraded with latest firmware, driving a 16x3W LED Spot parallel array load that got welded in few days.

    Link to comment
    Share on other sites

    • 0

    Hi guys

     

    What do you mean by the relay getting "stuck"? And how do you get it unstuck?

     

    I have a light that I am unable to switch off. It is actually a heatlamp (approx 700W) on a relay 2 (2 x 1.5kw). The other switch works fine, but this one I am unable to turn off through the fibaro app or from the wall switch. I have to turn off the mains which is a problem!

     

    Any ideas?

     

    Thanks

    Link to comment
    Share on other sites

    • 0

    @petergebruers Hi Peter! I suspect my double switch got stuck. I can see it being turned on and off in the HC2, but in reality the light stays on.  Is  "stuck"  the right diagnosis in this case? Should I take it out of the wall and knock on it?

    Link to comment
    Share on other sites

    • 0
  • Inquirer
  • It's possible. Yes, tap it with the back of a screwdriver. But maybe first disconnect the power to that circuit.

    Link to comment
    Share on other sites

    • 0

    I had the same issues with more than one Relay and I just knocked on them to become working, but they stucked again.

     

    The main solution is reducing the load or replace the tipe or lights model.

     

    Milano, Phillips, or Osram all working fine within the limit load.

    Link to comment
    Share on other sites

    • 0

    So is the overall conclusion, if you want to drive a LED light

     

    Please login or register to see this image.

    /monthly_2018_09/1678574090_LEDArmatuur.jpg.10260586cbe22549c27b28a54a872374.jpg" alt="1678574090_LEDArmatuur.jpg.10260586cbe22549c27b28a54a872374.jpg" /> 

     

    with a

     

    1559021792_dswitch2_diagrams1.png.5afc2150cc0894b4d52d77659e366c82.png

     

    add a ...

     

    130366_w01_stecker.jpg.d43a05092ffc1571652df4414d2ad10d.jpg

     

    ?

    Link to comment
    Share on other sites

    • 0

    What is this thing with yellow wires? My installer told me to replace the relay with a single switch... or replace the lights...

    Link to comment
    Share on other sites

    • 0

    Hi @Ros, it’s a device that you add inseries between your LED and your Fibaro switch. More info 

    Please login or register to see this link.

     

     

     Hi @petergebruers, what do you do if you have L1 and L2 and no N like here in Belgium (my home :))

     

    To all ... maybe someone can post a picture of his installation. For a lot of user a pictures says more then a text.

     

    Link to comment
    Share on other sites

    • 0
  • Inquirer
  • 15 hours ago, Sjekke said:

    So is the overall conclusion, if you want to drive a LED light

     

    The official advice is ... FGD-212 for LED. It was posted somewhere by Fibaro on this forum. It is an electronic switch, one that is well protected so the FGD does not "degrade" by the startup of lamps. On the other hand, if I would attach the load I presented in post #1 of this topic, then it would simply report "overcurrent" and refuse to turn on. So you know it is the load's fault, but it still does not turn on. And, there is another possible issue with that as well. The "Dimmer 2" passes a small amount of current and makes some lights glow faintly or "blink". Then you have to add a "bypass".

    FGS-223 + ESB1 is a possible combination too. I did not use this particular component, but it has been reported to work. The only possible downside: you really have to stay below 200 VA because there is a non-replaceable and it will blow...

     

    Please login or register to see this link.

     

    14 hours ago, Ros said:

    My installer told me to replace the relay with a single switch... or replace the lights...

     

    The single relay is bigger, so it has a bigger spring to pull apart the contacts, so it is less likely to stick (weld). Strictly speaking though, the manual says "resistive only"...

     

    Replacing the lights may work, because some have less inrush current. Unfortunately this is rarely specified for lamps. It is on the datasheet of "power supplies" though. But then again, Fibaro did not specify a limit...

     

    Adding a bigger relay after the FGS is another possibility, but then you get no power/energy monitoring.

     

    If you want to know more about relays and reliability I can recommend this topic:

     

     

     

    18 minutes ago, Sjekke said:

    what do you do if you have L1 and L2 and no N like here in Belgium (my home :))

     

    This is quite common in Belgium and France but not in Germany or the Netherlands. Just pick your own convention and stick with that. So N => L1 and L => L2 and the schematics will be OK.

    Link to comment
    Share on other sites

    Join the conversation

    You can post now and register later. If you have an account, sign in now to post with your account.

    Guest
    Answer this question...

    ×   Pasted as rich text.   Paste as plain text instead

      Only 75 emoji are allowed.

    ×   Your link has been automatically embedded.   Display as a link instead

    ×   Your previous content has been restored.   Clear editor

    ×   You cannot paste images directly. Upload or insert images from URL.

    ×
    ×
    • Create New...