More than a year ago I was approached by an independent filmmaker about light dimmers. The problem fo them was how to get affordable light dimmers to control the film lighting. I was told that many independent non-commmercial filmmakers use a HarborFreight router speed control to dim the lights used for moviemaking. The reason is that they are are cheaper and far heavier (15A) than building our own from a 600W house lights dimmer. The problem with these router speed control devices is that they do not dim down enough to turn the lights off. They also don’t quite go to full brightness but that is a minor problem as they have a switch that bypasses the electronics and provides full power.
After some discussion I got one of these units mailed to me to see if there is a way to modify those to work as better light dimmer.First thing I did was to open the device to see how it was built out. Based on what I saw the circuit was pretty close to a traditional light dimmer. And there seemed to be also some adjustment trimmer for some adjustments. Looked promising.
The nest task was to test the device. The problem that those are designed to operate 110-120V AC 60 Hz power has a slight problem to me. In Finland the mains power is 230V AC 50 Hz. Getting real 120V 60Hz power and finding 120V AC light bulbs is hard here where I live. I got one 120V lamp with the router speed control device so I had suitable lamp. Getting real 60 Hz power would involve some expensive power converter or using 12V to 120V AC true sinewave inverter or something similar that I did not have at the moment. So I decided to do my first testing with 110V 50Hz power that I get easily with a suitable voltage conversion transformer (I used fully isolating transformer for safety).
I did some testing. I found that the controller trimmer potentiometer controls how dim the output can go. I was able to get lamp very dim. Here is the picture of the dimmer electronics with a well insulated screwdriver adjusting the trimmer (there is a hole on the circuit board that gives access to the trimmer). Well insulated screwdriver and isolation transformer powering the whole circuit makes it possible to do ajustments with live circuit pretty safely when you know what you are doing. I mailed the results back to person who sent me the router speed control and he tested the results with real 60 Hz power (they worked).
The adjustment instructions: Set the potentiometer lowest setting. Then adjust the trimmer so that you get as dim light as possible without noticeable side effects. When you set the trimmer to too low setting, turning potentiometer will cause the output to be completely off (lap turns off). When dimmer reaches this full iff state, the dimmer potentiometer need to be turned quite much (one third or one fouth) until the light turns back on, quite bright already. The ideal setting I think would be that the lowest dimmer potentimeter setting would just set the bulb to be just barely on (lamp filament dark red and does not make much light), so you have always full control range from it to full setting without problems.
In this way a relatively cheap router speed control device is converted to a relatively inexpensive high power light dimmer.
Sir,
I need to know abt your dimmer system for NVG lab and whether it is compatible or not.
Compatible with specifically what?
Tomi,
Thanks! I use these controls on some motors, but noticed that sometimes I could not slow thing down enough. Your tip on the internal pot that could be tweaked was very useful.
Cheers!
Mark
I just Googled for cheap electronics and Got your Page.Your Post Router speed control to light dimmer « Tomi Engdahl’s ePanorama blog is really Nice.Pl. keep posting on cheap electronics
That was spot on! I could not have done that better at all haha. Hate to admit it though
I fully true!!! I think your site is nice !!! thanks for the story
Hello Tomi,
thank you for your post about the Router Speed Control.
I’m searching for a longtime for a 220v router speed control.
My question is off this speed control also useful is for 220v?
The factory says yes, see http://www.nb-dazhong.com/enprosoall.asp?mmm=3&sele=19&text=19&fl=Various
I hope you can help me.
Thanks Schummie.
I don’t know if this specific router speed control is also useful is for 220v.
The router speed control I receeived said in the box that only for 110V AC, and had USA power plug&jack in it.
The comment at http://www.nb-dazhong.com/enprosoall.asp?mmm=3&sele=19&text=19&fl=Various page
“The output voltage ranges from 100V to 240V” could mean that they have models available in those voltage ranges.
Maybe they have one model for 110-120V and other for 220-240V or so… That’s my quess.
Usually this kind of control circuits are just designed form one voltage.
It is technically possible to build the circuit that can handle the full voltage range, but it typically becomes more complicated.
And when with different voltages you always need two different products (different connectors), then when you have two
different models that have different connectors, then is no problem in changing few component values needed to adapt circuit
for different voltages. Or even optimize cost so that use lower voltage rated components (usually cheaper) for 110V model, and components
with higher voltage ratings for 220V model.
Hello Tomi,
thank you very much for your response.
I have a BOSCH Palm Router PR20EVS (Europe Bosch GKF 600) and this router has no speed control, in Europe they sell this Bosch palm router not with speed control.
I have problems to work with this router.
9 years ago I got a accident at my work. In the last 9 years I bin operated for 8 times and I have done a lot off rehabilitation but nothing wants to help.
The router speed is so high that it gives me a lot off pain when I use the router.
Therefore I’m searching for a speed control for my Bosch.
Does your speed control (from HarborFreight) on 220v?
Thanks for your help.
Schummie.
The speed control I have is model that is designed for 110-120V 60 Hz operation. It is designed for USA markets. It was sent to me from USA so I could check if it could be modified to that dimmer use. All it needed was some adjustment on internal trimmer.
I live in Finland where mains voltage is 230V 50 Hz. I tested that speed controller only with 110V 50 Hz power that I got from a transformer (I used both 230V-110V traveler converter and laboratory variac). I did not test that device with 220V, because I determined that 230V directly to it could destroy it.
I have not tested that with any router. I tested the controller only with light bulb to see how well it worked as cheap high power dimmer. And it worked for it.
I’m trying to find out what the best lighting is to make my property more safe at night. Are those solar powered lights worth it?
This is a very cool article, I could not have agreed more.
Great article. There’s a lot of good data here, though I did want to let you know something – I am running Redhat with the current beta of Firefox, and the design of your blog is kind of quirky for me. I can read the articles, but the navigation doesn’t work so well.
Hello, great day.. Your article is quite uplifting. I never thought that it was probable to carry out something like that until after I checked out your page. You undoubtedly offered an excellent understanding on how this whole process works. Ill always come back for more information. Thanks!
The above writing was great. I find it very interesting and I will surely forward this to my friends online. Anyway, thanks for sharing this.
Hiya, do you have a Twitter page that I may follow? With thanks
I do not have a Twitter page.
This post is good, whenever I just visit blogs I comes across some shitty articles written for search engines and irritate users but this article is quite good. It is simple, good and straightforward.
Hi – It’s great to read such topical writing on the Internet as I have been able to discover here. I agree with most of what is written here and I’ll be coming back to this website again. Thanks again for posting such great reading material!!
I really liked your blog! nice
I am quite interesting in this topic hope you will elaborate more on it in future posts
I’m willing to suspend my disbelief to enjoy a good show
Interesting post. Thanks for share
Interesting insight, amazed I never thought of that by myself
Wow! You really covered this topic well. Are there other resources that I should check out?
I would equal to add your journal to my blogroll gratify bowman me what mainstay should I use?
I have to say, that I could not agree with you in 100%, but it’s just my opinion, which could be wrong.
Nice website. Great online affiliate program. Thank you.
I find myself coming to your blog more and more often to the point where my visits are almost daily now!
Awesome job on this blog. Enjoying it alot hahah.
Subbed!
Keep up the great writing.
Your WordPress blog keeps getting better and better!
I’ve been following your posts for a couple of weeks now and I gotta say that your older articles don’t offer as much insight as the newer ones. You have a lot more creativity and style now, your writing is constantly improving.
BTW, if you’re looking into placing some ads on your blog – you should really do it. Don’t go for all that 3rd party crap – Use a nice WordPress monetization tool coded by a buddy of mine which by far the best, it’s a must have plugin for any serious blogger.
The BEST ad manager for WordPress. You can find it at Thaidy.com/BestWordPressPlugin and give it a free test-run (To make it easier for you, I linked my name to the site). Oh, and there is a nice discount coupon in the sidebar of the mainpage.
Keep up the good work buddy!
This is such a great resource that you are providing and you give it away for free. I enjoy seeing websites that understand the value of providing a prime resource for free. I truly loved reading your post. Thanks!
Great site. A lot of useful information here. I’m sending it to some friends!
hi it is my first reply on this web and to start with I would like to thank for the useful information, which I found in this and all previous posts , it really helped me a lot. I will definitely put this website on my rss reader
Also, I would like to ask – don’t you mind if I will quate some information from your website because I am writing articles for the Bukisa, Ezine and other articles directories (this is my part time job)? It would really help me with some of mine articles. Of course, I will mention your website name or URL (not all articles directories allows URL’s , so I can’t 100% promise that you will get a direct backlink to your blog).
Good! What a nice article! Just one suggestion:In case you then add images, it would easiler for you to stick to!by Air jordan shoes
Quoting a small part of the text is OK when you mention your website name or URL.
Thank you for articulating some great points. Whenever you read a news article warning I tried, too, is about power.by Air Jordan shoes
My friend recommended this blog I’ve currently just finished my master degree and found your information very useful
Aw, this was a really quality post. In theory I’d like to write like this too – taking time and real effort to make a good article… but what can I say… I procrastinate alot and never seem to get something done.
Want 2 thank you for ur insightful posts…
Hello, my group is just establishing our first website, searching and working out what is needed. This blog stuck out right away. I’m fired up about this, and adore the design of your site. Are you able to let me know what “theme” it is?
This site use a custom made “theme”.
I completely agree with the above comment, the internet is with a doubt growing into the most important medium of communication across the globe and its due to sites like this that ideas are spreading so quickly.
Hi. I wanted to drop you a quick note to express my thanks. I’ve been following your blog for a month or so and have picked up a ton of good information as well as enjoyed the way you’ve structured your site. I am attempting to run my own blog but I think its too general and I want to focus more on smaller topics. Being all things to all people is not all that its cracked up to be.
sometimes it is hard to write original articles for blogs but i always seems to manage creating fresh original content for blogs*-`
I admit, I acquire not been on this webpage in a extended time… in spite of that it was another joy to see It is such an leading text and ignored at near so many, even professionals. I recognition you to help making people more sensible of possible issues.
I agree with you.
I think you have a great page here… today was my first time coming here.. I just happened to find it doing a google search. anyway, good post.. I’ll be bookmarking this page for sure.
Great article! I am just starting out in all this and trying to learn more about it – resources like this article are incredibly helpful.