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RobotDyn AC Light Dimmer Module
greencardigan
I removed the Sil Pads and used some silicone grease instead. This is giving me better thermal transfer between the Triac tab and heatsink.

My heatsink temperatures were the same as previous but the Triac tab only reached 72C with the 3K/W heatsink and 52C with the smaller heatsink with 30mm fan. So that means the triac junction temperature should only be reaching about 91C in the worst case which I understand is quite reasonable.
 
renatoa
Yep, you did it right !
 
progen
Is it possible to just upgrade the triac itself to a higher rated one and match it with a larger heatsink if I were to use it to control a 5500w heating element? Can the PCB take it and do the resistors need to be changed?
 
renatoa
The PCB trace aren't capable of much more than 8-10 Amps, for a reasonable temperature increase, so you should consider cleaning the varnish and thickening them with solder.
Or soldering an additional wire from the triac pads to the terminals block.
Or, the best approach, separate the circuits completely into the power side: the triac on heatsink, fitted to power terminals accurately designed for this load, and the command side, i.e. the dimmer board used for ZCD and triac control via two tiny wires.
changing completely the layout to another more optimal approach, by splitting the circuits in
 
progen

Quote

renatoa wrote:

The PCB trace aren't capable of much more than 8-10 Amps, for a reasonable temperature increase, so you should consider cleaning the varnish and thickening them with solder.
Or soldering an additional wire from the triac pads to the terminals block.
Or, the best approach, separate the circuits completely into the power side: the triac on heatsink, fitted to power terminals accurately designed for this load, and the command side, i.e. the dimmer board used for ZCD and triac control via two tiny wires.
changing completely the layout to another more optimal approach, by splitting the circuits in


I think I'll stick to my initial plan of getting the Arduino to fire off pulses to the SSR then. Sounds safer to me.
 
renatoa
Right, what I suggested above is actually building a DIY SSR, without a case.
Electrical it's the same thing, but already done by a factory, so supposedly better and safer.
A SSR is the triac, in a proper case, with terminal screws designed for the right load.
The pulses from Arduino are the same wire that goes to dimmer board.
 
Yoku-San

Quote

progen wrote:

Quote

renatoa wrote:

The PCB trace aren't capable of much more than 8-10 Amps, for a reasonable temperature increase, so you should consider cleaning the varnish and thickening them with solder.
Or soldering an additional wire from the triac pads to the terminals block.
Or, the best approach, separate the circuits completely into the power side: the triac on heatsink, fitted to power terminals accurately designed for this load, and the command side, i.e. the dimmer board used for ZCD and triac control via two tiny wires.
changing completely the layout to another more optimal approach, by splitting the circuits in


I think I'll stick to my initial plan of getting the Arduino to fire off pulses to the SSR then. Sounds safer to me.


Maybe one solution that might help you:

I am using the AC Dimmer Module to dim a 1400W halogen heating lamp in an Air-Fryer (I posted the Mod here in the forum). But I am not directly dimming it: the air-fryer already contains a TRIAC with heatsink on its PCB which is also build for higher currents than the TRIAC on the Module. I found out that a small cable coming from the LCD of the machine was actually responsible for turning theTRIAC of the heating lamp on and off (so the air-fryer normally just switches between full and no power). Unfortunately, this cable was AC 220V.

So I used the AC Dimmer module to dim/PWM this low current gating line. And with this I get nice dimming of the second TRIAC and the heating lamp.

So you could use second TRIAC capable of handling high currents and gate it with a connection that you dim using the AC Dimmer Module (which already contains everything including zero cross detection). And you can use all the scripts and libraries that come with it and allow for easy implementation.

I hope that this maybe helps you.
Edited by Yoku-San on 02/01/2021 9:50 AM
 
progen
Thanks but I was a sound engineer in a former life and had gotten shocked a few times plus there's something about the sound of circuit breakers tripping that just gets on my nerves. My next build will be a pretty high powered (for a home build) one at at total of over 6000 watts and the Crydom 50A SSR that I'm looking at for the heating element comes to around USD20. Not worth me risking anything when I can afford USD20 and it comes in a nice casing with four nice terminals. Grin
 
Yoku-San
For your information:

RobotDyn has released a new AC Dimmer Module for use with higher loads including a bigger heatsink.

https://robotdyn....logic.html
 
renatoa
Great find !
Please notice how the great current traces were thickened with solder, to cope with the big current.

Alternative source:
https://www.aliex...51718.html
... if the shipping from RobotDyn is shocking expensive, as is case for my country... $39 with DHL
 
renatoa
Another finding on Aliexpress... while browsing to see what's new.
This seller, which is actually the RobotDyn Official Store:
https://www.aliex...25086.html

... has an "embedded" version of the dimmer, is just another board layout, for those who prefer soldering heater circuits, instead screw terminal block. Is half price versus the normal version !
Also, he is selling a DIN rail adapter, for the older dimmer board, if anyone use DIN rail for his setup.
 
progen
I finally got mine. Weird how I had to get it via Indonesia. Came up to around USD7 - 8 shipped.
 
greencardigan
Is that a snubber circuit I see on board?
 
renatoa
If you mean the circled RC from attached image, yes, as value and placement, quacks like a snubber.

...
renatoa attached the following image:
top_3_snub.jpg
 
greencardigan
I've just been testing out the new 16A RobotDyn dimmer. Other than the heavier pcb traces, I don't think it offers much over the original version.

The heatsink is slightly bigger, but I think it still requires a bigger heatsink or some forced airflow to keep it's triac at a reasonable temperature when switching an 1800W 240V heating element.

I also recommend replacing the sil-pad with some thermal paste.

For an inexpensive controller setup for a small AC roaster I would recommend a Rotordyn AC dimmer controlling the AC fan and also providing the zero cross signal. For the heater I'd recommend using a zero crossing SSR such as the Crydom D2425.

A separate zero cross detector and instantaneous fire SSR is still my recommended setup for larger AC fans.
 
renatoa

Quote

greencardigan wrote:

Other than the heavier pcb traces, I don't think it offers much over the original version.


The snubber ? Bigger terminals block, better suited for increased current.

Quote

greencardigan wrote:

I also recommend replacing the sil-pad with some thermal paste.


... but first check what you have on your actual copy... mine all 3-4 units are with thermal paste from the factory, no silicone pads.

My new models are still on the way from Chine, somewhere in the Netherlands Post yesterday.

As already wrote I am using the original board for some two years on a 1300W 230V TO without issues, in open air, no forced venting. About 60C degrees at heatsink surface.
For me is no way back to the traditional SSR usage, at least for this power level.
Even for more power I don't see the point for a separate ZCD, when this board is exactly the same, at third price.
You can simply use the triac on board to drive a bigger SSR, and you are done.
 
greencardigan
I have 4 original units and one 16A unit and they all have had sil-pads.

True, using these as the ZCD even when using a bigger SSR is most economical, although perhaps it is a bit more confusing for inexperienced users.
 
renatoa
New version, with embedded 3.3 or 5V power source:

www.aliexpress.co...07055.html
 
jake415
For some reason I am not able to get the TC4 to communicate properly with the robotdyn and I have a feeling it's a software issue but am not sure.

Do I need to modify the standard TC4+ code to accompany the robotdyn or should it work as is?
 
renatoa
Please describe "communicate properly"
I can't image other issue than the PWM signal source: should be from Arduino board GPIO pin, not for TC4 OT1 output, which is for driving a SSR, using a reversed logic.
ZC signal from robotdyn board is a direct connection to Arduino interrupt pin.
 
jake415
Right now I'm just testing the heater side since it seems simpler (no ZC). The PWM signal is connected and should work.
When I use CONFIG_PAC3 for phase angle control on heater, and test the robotdyn (Vcc to OT1, PSM to GPIO PIN 9), there are no flashing lights and the robotdyn seems completely inactive. When I use CONFIG_PWM for PWM on heater, same connections, there are flashing lights and the robotdyn works. I'd like to use phase angel control but so far no luck.
 
renatoa
PAC requires ZCD, that's why is not working
Without ZCD only PWM is available.
 
jake415
I didn't know that, problem solved ThumbsUp thanks
 
dpecsok
hello!
im using the RobotDyn module to control an 1200w AC vac motor using PAC2 mode. ive been testing with both the motor and a lamp as well. problem is that the motor or light is either OFF or at 50% and higher. below 50% it seems motor and light are bit jittery like its being pulsed on and off. any suggestions is very much appreciated!
dpecsok attached the following image:
screen_shot_2022-03-14_at_13135_pm.png
 
dpecsok
i read in a few other posts that this is common using PAC. i there a way to control the RobotDyn using PWM mode? if so what is the proper way to wire it? sorry im a noob ha!
 
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