Shutting power to TPA3255 daily

When the amplifier is switched off, it continues to operate for a while (using the stored charge in the bus capacitors) before it browns out. This is unlikely to damage the amplifier or the power supply. The consequences are mostly related to lifetime and long-term reliability. Since the amplifier is not operating all the time, its remaining useful lifetime would be preserved, resulting in better life expectancy in general.

However, it may be better not to turn off the amplifier every few minutes / hours, as that could cause thermal cycling of the internal junction. Note that this kind of temperature cycling is aggravated by cold climates, since the junction would also have the opportunity to cool down to room temperature in between usages. Nevertheless, in temperate / tropic climates, it's OK to turn on few minutes before usage, as the room temperature doesn't fall that low.
 
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First think what will happen to the user at the extremes of that temperature range.
70 C water will burn your skin.
0 C water will be ice.
Can you listen to music then?

If he is using a timer, then a simple 4.7 M across the secondary caps will draw them to safe before brown out.
Then also SSR after timer will work for switching...

Question is, why timer?
Where is the need for a timer except in a commercial setting?
What else in the building has timer control?
Are there inductive loads which can cause kicks in voltage?
If yes, set timer to shut down amp before HVAC, and start at least 10 minutes after HVAC does.

And drain time of capacitors?
And how is this amp going to behave in a normal house, will it have the same life issues?
What is the power supply to be used at home? Different or similar?

Also, how many dollars does amp cost?
100 US at most....
No need to think so much.

The cycling does not have as much influence on life as the working temperature and supply voltage.

Location and climate are not given...
 
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And look at the creep curves for life expectancy, properly run at right voltage and temperature, you are limited by capacitor life, not junction temperature.
Capacitors fail earlier than semiconductors.

15000 hours at 12 hours a day is several years.
 
The smart switch only controls the amplifier, no other load is involved.

I use the smart switch to turn on/off the amp everyday, whether it's via a timer or manually. I don't like to leave the amp on overnight. I just don't want the ON/OFF action to burn out the amp after 2 months.
 
Plenty of discussion about this amp in the diyaudio forum. May not be the highest quality, but plenty of people interested in using it.
Discussion and interest in something does not make that something better than it is.
And the reputation of places like aliexpress isn't a source of quality components.
Nevertheless, it seems people flock to such places for the cheap prices.
And the old saying - you get what you pay for - becomes clear.
 
If the smart switch turns power on and off at the 0 crossover point it is probably better than using a wall switch which turns power on and off possi ly at the peak voltages. How many times have you turned something on and it fails. It worked perfect yesterday. I used to hate working during the summer thunder storm season. Power surges, brownouts and power outages that lasted only a half second would cause plenty of service calls. Data centers that spent small fortunes on UPS systems were much more reliable than those that just used the local hydro utility.
 
If the smart switch turns power on and off at the 0 crossover point it is probably better than using a wall switch which turns power on and off possi ly at the peak voltages. How many times have you turned something on and it fails. It worked perfect yesterday. I used to hate working during the summer thunder storm season. Power surges, brownouts and power outages that lasted only a half second would cause plenty of service calls. Data centers that spent small fortunes on UPS systems were much more reliable than those that just used the local hydro utility.
If something is as FRAGILE as requiring "zero crossing" powerline switching for protection and reliability, it's a crap design.
 
It is a stupid audio amp, not a data center.
It is running off an external SMPS, what is this nonsense of zero crossing switch?
And the OP has avoided the question of need for timer.
An ordinary switch will work, so will any timer.
And the load...is not so big as to worry about inductive issues.

Another odd person, maybe he had a switch lying around and decided to use it!
 
The original poster asked if he could use a smart switch to control his amplifier. I suggested that a smart switch may be more reliable in the long term than a simple on off switch. Maybe Notakosan lives in an area with unreliable power. Maybe he just wants to be able to turn his system on and off via his phone or tablet. I dont know. People have started to install smart lighting and smart switches to control many devices in their homes. My neighbour controls his pool temperature via his phone. The local Hydro utility wants to install remote smart thermostats to control the temperature inside peoples homes during times of heavy hydro demands. I said not in my house please.

Devices that use zero crossing generate smaller surges and less EMI, they improve reliability. Why do so many people here install a soft start in their systems.
 
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Don´t-overthink-it 🙂

I use the smart switch to turn on/off the amp everyday, whether it's via a timer or manually. I don't like to leave the amp on overnight. I just don't want the ON/OFF action to burn out the amp after 2 months.
Why?
And why make it independent of actual use? That´s nonsense.

When you want to listen to Music: turn it ON

When you are done, turn it OFF

What 99.99999999999999% of people do.