Discuss LED 'Dummy Load' in the Electrical Forum area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

Reaction score
0
I'm having no end of issues with a current install.

What I've got is two 3gang dimmer switches from Lightwave RF.

Gang 1 - Auraled 240v 5w Warm White LED Dimmable Lamp x4
Gang 2 - Auraled 240v 5w Warm White LED Dimmable Lamp x6
Gang 3 - Auraled 240v 5w Warm White LED Dimmable Lamp x2
Gang 4 - 2x 60w Incandescent Lamps
Gang 5 - Auraled 240v 5w Warm White LED Dimmable Lamp x4
Gang 6 - 12V ELC under cupboard halogen lights x4

I've tried many different products with this dimmer finding that these AuraLED lamps work the best for dimming.

However, when the dimmers are turned off, there is a small amount of current getting to these lamps causing a residual light to come from these lamps. This is easily eradicated by putting a 50w halogen lamp in each circuit. This as I'm sure you can understand isn't aesthetically pleasing so I've been trying to find a way to replicate the capacitance of the 50w halogen lamp to no avail! Is there anyone out there with any solutions/suggestions please?............
Without just chucking a 50w lamp into the ceiling void! I have already been tempted but I can't do it!
 
Induced voltage being high enough to cause the lamps to operate should be able to be removed by the use of a contact suppressor or RC snubber, close to the lamps, if possible. Some recommendations from this forum have been these or these.
 
I'm having no end of issues with a current install.

What I've got is two 3gang dimmer switches from Lightwave RF.

Gang 1 - Auraled 240v 5w Warm White LED Dimmable Lamp x4
Gang 2 - Auraled 240v 5w Warm White LED Dimmable Lamp x6
Gang 3 - Auraled 240v 5w Warm White LED Dimmable Lamp x2
Gang 4 - 2x 60w Incandescent Lamps
Gang 5 - Auraled 240v 5w Warm White LED Dimmable Lamp x4
Gang 6 - 12V ELC under cupboard halogen lights x4

I've tried many different products with this dimmer finding that these AuraLED lamps work the best for dimming.

However, when the dimmers are turned off, there is a small amount of current getting to these lamps causing a residual light to come from these lamps. This is easily eradicated by putting a 50w halogen lamp in each circuit. This as I'm sure you can understand isn't aesthetically pleasing so I've been trying to find a way to replicate the capacitance of the 50w halogen lamp to no avail! Is there anyone out there with any solutions/suggestions please?............
Without just chucking a 50w lamp into the ceiling void! I have already been tempted but I can't do it!

This does sound like you might need some dummy loads. This kinda defeats the whole object of using LEDs i know, but you probably are running under the minimum dimming capability. I've not much experience with Lightwave however I have experience designing and installing other brands of lighting control systems and nearly all of them will have a minimum wattage dimmable per channel, it's normally around 40-50W

I don't know why you're mentioning capacitance with regard to 50W GU10s as there won't be any, what you want to replicate is the resistance. A 1kΩ resistor in parallel should do the trick.

Try one of these next to one of the LEDs on each circuit (bar circuits 4 and 6): Buy Panel Mount Fixed Resistors HS50 Al house wirewound resistor,1K 50W Arcol HS50 1K J online from RS for next day delivery.

Utilising a couple of recepticle connector crimps, these fit nicely into a wagobox which in turn fits snugly through any downlight hole. Be sure to drill plenty of 1mm holes in the wago box though for airflow!

Let me know how you get on :)
 
Last edited:
This does sound like you might need some dummy loads. This kinda defeats the whole object of using LEDs i know, but you probably are running under the minimum dimming capability. I've not much experience with Lightwave however I have experience designing and installing other brands of lighting control systems and nearly all of them will have a minimum wattage dimmable per channel, it's normally around 40-50W

I don't know why you're mentioning capacitance with regard to 50W GU10s as there won't be any, what you want to replicate is the resistance. A 1kΩ resistor in parallel should do the trick.

Try one of these next to one of the LEDs on each circuit (bar circuits 4 and 6): Buy Panel Mount Fixed Resistors HS50 Al house wirewound resistor,1K 50W Arcol HS50 1K J online from RS for next day delivery.

Utilising a couple of recepticle connector crimps, these fit nicely into a wagobox which in turn fits snugly through any downlight hole. Be sure to drill plenty of 1mm holes in the wago box though for airflow!

Let me know how you get on :)


Two points:
1) The minimum wattage dimmable isn't relevant here, because the problem occurs when the dimmer is switched off.

2) I hope you're joking about the 50W resistor in a box.
 
Like I said, I have no experience with lightwave but with other dimming systems, the dimmers can never be set to off, just 0%, this is why it could be relevant here.

Secondly, why would I be joking about the resistor in a box? Some lighting control manufacturers sell these as all in one items for exactly the purpose I was talking about except they are horrendously expensive! All they are is enclosed resistors with massive heat sinks. Its not the ideal solution, I design my circuits and loading capacities so that they are never needed.

Can you find me a reg that says you can't use a resistor as a load? If so, I'll happily eat humble pie :)
 
Definately can't see the sense of putting nice new LEDs in and then dumping 50W of heat out into the ceiling void. Daz
 
Like I said, I have no experience with lightwave but with other dimming systems, the dimmers can never be set to off, just 0%, this is why it could be relevant here.

Secondly, why would I be joking about the resistor in a box? Some lighting control manufacturers sell these as all in one items for exactly the purpose I was talking about except they are horrendously expensive! All they are is enclosed resistors with massive heat sinks. Its not the ideal solution, I design my circuits and loading capacities so that they are never needed.

Can you find me a reg that says you can't use a resistor as a load? If so, I'll happily eat humble pie :)

I take your point about some dimmers never actually going to "off", although the usual type of small dimmer has a hard "off" switch.


I've used these metalclad resistors before, for something else, and took another look at the data sheet.

At 230V, it will be dissipating 52.9W. These resistors will only safely dissipate their rated power when mounted on a large heatsink. With no heatsink, and at 25C ambient, the "50W" device is rated at 20W, and the surface temperature will probably be enough to melt its way through a Wagobox. (Think how hot a 50W GU10 gets, even when hung in fresh air.)

You certainly don't need anywhere near this size of dummy load in a normal domestic situation. See the post from Richard Burns.
 
Fair point, but when I've seen these fitted before (I've never fitted them personally), they have been fitted with the heat sink included. The premade units I mentioned pretty much look like a selv tranny but with hundreds of fine holes in its casing. I can't see a 1kohm resistor with heat sink melting a ventilated wagobox, but I suppose you're right.

I suppose another way of doing it would be to take the circuit back to the db and mount the resistors in free air, but then that still not only defeats the objective of using LEDs, but also completely defeats the objective of using Lightwave RF haha.

On a final note, I'm almost certain that this is a loading problem and has nothing to do with inductance and/or capacitance other than you could use reactance to simulate load.
 
Last edited:

Reply to LED 'Dummy Load' in the Electrical Forum area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

YOUR Unread Posts

Electrical Forum

Welcome to the Electrical Forum at ElectriciansForums.net. The friendliest electrical forum online. General electrical questions and answers can be found in the electrical forum.
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock