5V MCU connect to 230v Bulbs

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PA3040

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Dear All,

https://www.youtube.com/watch?v=yJ_cTFIFl7s

I would like to design light system using MCU as showing in above youtube video

The bulbs are used 230V 40w and 230v 5w

In my case we decided to use less than 1000 bulbs ( 230v 40w and 230v 5w)

I am expecting to program micro controller for light patterns

Please advice what is the most cheapest and relabel way to connect 5v MCU and 230v Bulbs

Thanks in advance
 

Sounds like an expensive project!

There are probably a number of ways to do this; logic-level triacs might be one.
 


There is no reliable way to use bulbs, Las Vegas has gone to LEDs.. You can get 5m strips of RGB LEDs with many different power levels and sizes avail some with I2C controllers built in.

This is the only way i would do this and the approach you should consider.
 

barry said:
Sounds like an expensive project!

There are probably a number of ways to do this; logic-level triacs might be one.
Click to expand...

Yes it looks like expensive and I think it does not have solution by electronic engineering and still conventional method is cheap
 

I doubt your comment since the cost of a thousand Triacs to switch a thousand incandescent bulbs is hardly cheap, not to mention the failure rate of 1500~3000h will rapidly decline with the rapid surge current switch rates and also the costs for electricity and breaker panel upgrades.
 
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    PA3040

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Can you please advice for how minimize wiring diagram which can control every bulb individually using triac

- - - Updated - - -

barry said:
Sounds like an expensive project!

There are probably a number of ways to do this; logic-level triacs might be one.
Click to expand...

Can you please advice what is the different logic level triac and none logic triac
 



Then opto-isolated zero crossing driver pulse. Either ZCS built-in or ZCS pulse OR'd with logic which is detected by zero crossing detector from CA line. ( Diode bridge current inverted)

Each triac must handle >5x rated [W] load for entire row or column when pulsing tungsten lamps due to surge currents even with ZCS otherwise they all blow.
 
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Can you please explain important of zero crossing detection on this project
 

Rapid pulsing of tungsten lamps can cause average power loss in Triacs to increase rapidly as surge currents for cold lamps can be 5~10x steady state. Thus ZCS Triacs or a ZCS pulse gated with any logic level drive reduces the worst case inrush somewhat but can last more than a half cycle depending on size.

more importantly it reduces EMI from high dI/dt.
 
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Thanks for the advice

You mean the gate of triac should on at the zero crossing
I am I correct?
 
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Basically, yes.

A triac needs at least 2 V on AC across device , so nothing happens exactly at leading edge of zero crossing, but pulse width enables latching just after zero crossing then disables trigger until next.

Either full diode bridge or XOR or XNOR gives this response for desired threshold with some noise filter that does not delay zero crossing of fundamental.

This assumes of course that you do not want to perform dimming.
 
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Thanks for the reply

Actually my main requirement is to reduce the failure rate of the TRIAC

As per AC signal 230V 50Hz mean 1/50 = 20ms for one full sign wave and for half wave 10ms. So then we can calculate RMS and average voltage.

So may question is. Since there is no enough brightness with incandescent bulbs tern on triac at the zero crossing( falling edge of zero cross detector ). Therefore we can use 2ms delay just after zero crossing to tern on the triac. Is this increase the failure rate of triac?

Please advice
 

Typically ZCS inhibits triggering when AC is > 5V.
This allows smooth turn on, But cold filament can be as low as 10% of normal hot resistance thus current surge still exists.

I suggest you perform tests for your lamps with transient rates of maximum flashing rate and measure the current and heat loss in Triac.
Depending on bulb you then size power Triac to match requirements for desired temp rise.

This can be used to trigger power Triac
**broken link removed**
 
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Thanks for the reply

Can you please advice the most efficient and easy to use of following two methods

1.Using zero crossing detecting optocupler (MOC3062), we can ignore the zero crossing interrupt from MCU.
2.Using none zero crossing detection optocupler ( MOC3021) we have to manage it using external interrupt of MCU( Like RB0 of PIC16F877a).

What should be the most relabel and easy way from above two suggestions

Please advice
Thanks in advance
 

A common ZCS pulse seems easiest. It can start before Zero and end after zero V. A simple detector on scaled rectified line voltage will achieve this with spike suppression on line for added blocking of triggers when line voltage is >+-5V . It is just enabled near zero crossing and disabled otherwise with any logic, either in each opto or in micro.

I once made a chaser for a musician friend long ago using small light bulbs to sequence the bulbs for each letter of the band's name in the sign. When their Tech rewired these 15A Triacs to 5A floodlights they kept blowing Triacs due to rapid repeating surges, even though it had ZCS control.

So again bulb and flash rate are critical to choice of Triac rating.

For the same reason, dimmer Triacs rated for 10 A often fail on 1A CFL's due to magnetic surges unless PFC corrected or "dimmable"
 
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Dear Sunny Thanks for the advice

Can you please advice the number of Triac which can handle high current

I purchased BTA41-600B for testing but not tested , Can you recommend better than this triac

Thanks in advance
 

SunnySkyguy said:
What bulb and what is the max. Pulse Rate for a ZCS triggered Triac?
Click to expand...

Bulb is 5W 230V ( 4 8x8 matrix) 256bulbs incandescence


What should you mean Pulse Rate for a ZCS triggered Triac?????
 

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