Sudden Spike in power

[deblen]

Hi,


Last night talking with Ryan (ryanschristmas)' we're he may have has a sudden spike from his power supply to his Pixlite, set at 24 volt, but may have jumped an extra couple of volts, board is now in repairs.


I am going to run some of my. Oars at 24 volt, which is the high recommended voltage, I am using buck to bring voltage down to 5v at the pixel.


Is there any thing that I may place between the power supply and controller board to prevent a spike, to protect the board.


Also the same at the buck end, prevent a spike going over 5 volts,


Any suggestions appreciated.


Deblen

 

[Benslights]

I know Alan is working on something for the P10 panels. do not think there is a simple answer to this with so many different voltages being used.

I'm sure the brains trust may come up with something

 

[fasteddy]

What you need is a DC surge protector/surpressor. There are many types available and are mainly used in industrial machinery applications.

The question is why did you get a surge from a regulated DC power supply unless there was an issue with the power supply or you have got induced voltages due to running mains power cables along side the low voltage DC lines

 

[fasteddy]

Here is a link to a relatively cheap one on Ebay which is rated for 12 to 24vdc, not sure how good this one is though

http://www.ebay.com.au/itm/1-Pair-12V-24V-Low-AC-DC-Power-Surge-Protector-Device-Lightning-Arrester-SPD-AU-/121527005432?hash=item1c4b92f0f8:g:G5AAAOSwECZUm48H

 

[AAH]

To answer Ed's question it's next to no good based on the specs.
Specification:

• Nominal working voltage Un: 12V - 24V
• Max continuous operation voltage Uc: 36V

If the maximum voltage is 24V or pretty close to it the max operation voltage that that unit can handle makes it no protection at all

Here is a link to a relatively cheap one on Ebay which is rated for 12 to 24vdc, not sure how good this one is though

http://www.ebay.com.au/itm/1-Pair-12V-24V-Low-AC-DC-Power-Surge-Protector-Device-Lightning-Arrester-SPD-AU-/121527005432?hash=item1c4b92f0f8:g:G5AAAOSwECZUm48H

 

[fasteddy]

To answer Ed's question it's next to no good based on the specs.
Specification:

• Nominal working voltage Un: 12V - 24V
• Max continuous operation voltage Uc: 36V

If the maximum voltage is 24V or pretty close to it the max operation voltage that that unit can handle makes it no protection at all

Here is a link to a relatively cheap one on Ebay which is rated for 12 to 24vdc, not sure how good this one is though

http://www.ebay.com.au/itm/1-Pair-12V-24V-Low-AC-DC-Power-Surge-Protector-Device-Lightning-Arrester-SPD-AU-/121527005432?hash=item1c4b92f0f8:g:G5AAAOSwECZUm48H

I had a feeling it might have been junk. All the cheap ones basically do nothing, you have to spend over $100 for a decent one

 

[multicast]

A low cost and effective solution is to use a suitably sized TVS diode. You place them across your power supply in reverse bias. That is to say the anode ( + ) goes to the gnd side and the cathode (-) side goes to the +v side. When everything is happy the diode does nothing. But if the voltage goes over the breakdown voltage of the TVS diode the diode starts conducting effectively dead shorting things and your spike is absorbed. Once the spike goes away things return to normal.

TVS diodes range from a few volts to hundreds and power ratings. And are only a few cents to tens if cents

 

[AAH]

I was looking at TVS diodes as a protection method. They are excellent for protecting against a momentary spike but if the power supply voltage stays high then they can very rapidly overheat. I have actually just been having a discussion with David_AVD with the relevant methods of overvoltage protection.

-TVS diode. super fast, cheap, self resetting. can't withstand a consistent overvoltage
-crowbar circuit with fuse. more complex and expensive than TVS diode. not quite as quick as TVS. blows a fuse so isn't self resetting. positively disconnects the power from the circuit
-crowbar circuit with mosfets. most complex, expensive and slowest. disconnects while overvoltage and reconnects when not

 

[BundyRoy]

I might be wrong but I thought the pixlite could handle input voltages of between 5 and 30V (pixlite 16 anyway). So a couple of volt increase from 24V shouldn't have caused any damage. Am I missing something or does that mean the spike was above 30V. 25% increase seems like a lot.

 

[multicast]

I was looking at TVS diodes as a protection method. They are excellent for protecting against a momentary spike but if the power supply voltage stays high then they can very rapidly overheat. I have actually just been having a discussion with David_AVD with the relevant methods of overvoltage protection.

-TVS diode. super fast, cheap, self resetting. can't withstand a consistent overvoltage
-crowbar circuit with fuse. more complex and expensive than TVS diode. not quite as quick as TVS. blows a fuse so isn't self resetting. positively disconnects the power from the circuit
-crowbar circuit with mosfets. most complex, expensive and slowest. disconnects while overvoltage and reconnects when not

The OP did say "Spike". I was trying to stay on topic with an answer about how to protect from spikes.

 

[EmmienLightFan]

Why not run the controller at 5v? Extra layer of protection and a buck converter is cheap and hopefully you already have spares.

 

[multicast]

I was looking at TVS diodes as a protection method. They are excellent for protecting against a momentary spike but if the power supply voltage stays high then they can very rapidly overheat. I have actually just been having a discussion with David_AVD with the relevant methods of overvoltage protection.

Hopefully you are using a resonable Power Supply and its going to not go overvoltage anyway. Spike are something dont' nessarily orginate from the power supply. Do you know you can get several hundred volts out of a length of cat5 cable, just by rubbing it up and down on some carpet?

 

[deblen]

Hi, hope everyone had a great start to the New Year.


Thanks all for the replies.


I am glad I asked the question re spikes. I have been putting together Falcon F16 controller, 12v and 24v, Pixlite 16' and changing the Pixlite 4 controller boxes to suit the LED voltage, changed from a Buck, to straight to the 24v power supply.


Thanks to Bundy Boy post, I rechecked the Pixlite 4 power, OH NO, it is max 18 volt, I have put 24v into one of the boards.


My mistake, with all the different power supplies and boards, I have been caught out, thinking 24v.


This is a lesson learnt.


This has made me think, my original question, if I had something in place to prevent a spike, or indeed protect the board, if I did above, or the power supply has a hic cup.


Thanks. Deblen

 

[lizardking]

after i smoked my p12s , it had jumpers set to 5v and i put a 12v PSU on it i only power my boards with 5v and my 12v lights are powered from the PSU via a fuse block so all my boards are power by 5v so I dont make another mistake maybe this may help your problem