# TC420 to Control Analog 0-10v dc



## RLee (Sep 21, 2008)

I wanted to use the TC420 to control a analog ballast using 0-10v dc. I read that the TC420 will output 10v PWM signal if it is powered with 10v dc. Then I would use this https://www.amazon.com/KNACRO-Conve...rd_wg=vXRWf&psc=1&refRID=6QRWSKV62ZB5EHR7NYNZ to convert the 10v PWM signal to 0-10v analog. I do not know the output frequency of the TC420, some places say its 500hz some 1khz. The frequency of the convert claims it needs a signal between 1khz - 3khz. Would it still work if the input frequency was 500hz?


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## jeffkrol (Jun 5, 2013)

You can just do a passive RC circuit to smooth the 10V PWM to analog..
https://electronics.stackexchange.c...tant-in-pwm-digital-to-analog-low-pass-filter

Pretty sure thefrequency is arond 490Hz like Aduino's..


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## RLee (Sep 21, 2008)

I ordered the parts they should be here tues. I have a feeling, like most electronics, that there is a broad spectrum outside the recommended values that they will work. We will see.


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## ChrisX (May 28, 2017)

RLee said:


> I ordered the parts they should be here tues. I have a feeling, like most electronics, that there is a broad spectrum outside the recommended values that they will work. We will see.


This is a cool idea. Using PWM controller for a 0-10v analog control.


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## RLee (Sep 21, 2008)

The TC420 Controller and PWM to 0-10v d.c. analog converter work perfectly. The PWM converter works with any PWM signal from 4.5v to 24v. It says it needs a input frequency between 1khz-3khz. The TC420 uses a 600hz but this was not an issue. I was worried that the frequency would be an issue. None of the websites that were selling the TC420 had this info available! All they had to do was take a pic of the damn instructions. Anyway there is an adjustment pot on the PWM converter that you can fine tune the 0-10v d.c. ouput for varying PWM input frequencies.
I did run into a slight snag, the voltage input for the converter is between 12-24v. I had a 12v power supply handy but the PWM converter would only output 9v max. I also had a spare laptop PS that was 19v. With this I could get the full 10v output. I don't think I needed a 19v PS maybe anything < 14v would of worked.


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## jeffkrol (Jun 5, 2013)

Glad it worked. 
Was more worried at low dim levels like 10%

When I measured it , roughly, was around 540-ish...but really didn't trust my old meter as to real accuracy..
Only could say under 1kHz..
The 3V "loss" isn't unusual..


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## RLee (Sep 21, 2008)

Now if only I could modify the firmware to allow you to use any saved mode with a particular day of the week. For instance mon-fri use mode 1 program for the lights "7am - 3pm". Then on the weekend sat-sun use mode 2 program for the lights "9am to 5pm".
I can do this now but have to manually switch modes. You can set the date in the setup menu but currently what is that used for?



jeffkrol said:


> Glad it worked.
> Was more worried at low dim levels like 10%
> 
> When I measured it , roughly, was around 540-ish...but really didn't trust my old meter as to real accuracy..
> ...


You were real close and helped my decision making. Its just funny how many questions these seller would answer by simply posting a picture of the instruction manual that comes with the unit. Really they wouldn't have to type out anything else.
I use phillips t5-ho dimming ballasts. They dim 1%-100% via 0-10v analog low current, less .5ma.


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## Cyberlocc (Jul 28, 2018)

RLee said:


> Now if only I could modify the firmware to allow you to use any saved mode with a particular day of the week. For instance mon-fri use mode 1 program for the lights "7am - 3pm". Then on the weekend sat-sun use mode 2 program for the lights "9am to 5pm".
> I can do this now but have to manually switch modes. You can set the date in the setup menu but currently what is that used for?
> 
> 
> ...


Sorry to bump the semi old thread. However I need to accomplish this exact thing, also can you link me the T5 ballast it worked with? Was it the advance 0-10v? 

However, does it dim to the 1%? Or dim very low? 

And not to sound dumb lol, but how do you with this up to the Amazon part? Does it come with instructions? 

Thanks in advance.


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## jeffkrol (Jun 5, 2013)

> Philips Advance Mark 10 Powerline dimmable ballasts ...Full-range continuous dimming
> (100% light output down to 5%;
> T5HO to 1%)


Need to check your specs as to how far down it dims..

As to instructions.. probably, sort of:









http://mjrobots.com/product/pwm-0-10v-digital-to-analog-signal-tranformer-converter-module/
http://mjrobots.com/wp-content/uploads/2016/03/s-l500-9.jpg


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## Cyberlocc (Jul 28, 2018)

jeffkrol said:


> Need to check your specs as to how far down it dims..
> 
> As to instructions.. probably, sort of:
> 
> ...


Thanks for the links, as for the bulb he said he has a phillips bulb that dims 1% to 100%, so I was wondering what bulb that was. 

I am finding alot of trouble finding any T5HO ballasts, must less ones that go to 1% lol. He said Phillips though, and the advance is the only Phillips one I have seen. 

Does the TC 420/421 go that low?


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## jeffkrol (Jun 5, 2013)

Cyberlocc said:


> Thanks for the links, as for the bulb he said he has a phillips bulb that dims 1% to 100%, so I was wondering what bulb that was.
> 
> I am finding alot of trouble finding any T5HO ballasts, must less ones that go to 1% lol. He said Phillips though, and the advance is the only Phillips one I have seen.
> 
> Does the TC 420/421 go that low?


That's a driver/ballast thing.. 



TC goes from zero to 100% in, assuming, 256 steps..


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