Power Supply keeps blowing up


#1

Hi,

My Pi is on its 4th power supply in 3 months. The power supply keeps failing and I am assuming this happens when there is electrical activity in the air. The antenna has not been hit directly, but we do get a lot of storms around here.

The Pi was previously connected via ethernet to my internet router, but after some electrical activity (in the sky), the router blew up (and destroyed an ethernet port on a computer also connected to the router). I have since changed to a WIFI dongle but now its the power supply that keeps going.

Is there any way I can prevent this?

I’m running Flight Aware stick and filter and 3 metre length of coax attached to a quarter wave length antenna on the top of my roof. (one like this one jeroen.steeman.org/Images/1090-quarter-wave.jpg).

Does any one have any suggestions?

Thanks

Haydn


#2

If the power supply dies but the Pi is intact, that sounds like the problem is on the mains side, not the Pi side. You might want to try something to condition the mains.


#3

I’d bet if you checked your mains voltage with a good voltmeter, it’s over 250 Volts, npt the 230 Volt nominal – seeing that you’re in Australia. With high mains voltages, power line spikes can easily take out equipment built for nominal 220 V Euro use.

If this is the case (and it’s just a guess), it’s hard to suggest an inexpensive cure, other than looking for wall warts or similar power supplies designed for local use. You might talk to local ham radio operators, or the local electronics maker community, other folks who may have experience with these issues.

bob k6rtm


#4

What kind of power supply are you using?


#5

It could very well be static build-up in the antennas “ground”, connected by the coax shield, through the stick to the DC-, which goes straight to the power supply - side.

Is there any real ground connection from the coax or antenna mount to true ground? Like a ground rod or similar?

/M


#6

Do you have a lightening arrestor? Probably a good idea. Also a UPS if you don’t already have one. It might be some random spikes on the AC which is normal. Though standby UPSes don’t really catch those… but they should catch flickers and brown outs, which are what really damage equipment more than anything.


#7

The braid of my coax is grounded (in fact it’s the mast that is grounded to a long spike in the ground, but electrically it’s all connected together).

I’d ground the coax braid as a minimum, doesn’t need anything fancy - a croc clip onto the outside of a connector will do.

A lightening arrester with good grounding would be the target though.


#8

I fully agree with Oliver (obj) & Bob (k6rtm).
It is mains problem, over voltage and/or voltage surges on power line.


#9

Even without storms, and exposed antenna will pick up static electricity from the wind. A lightning arrester will help with that.

telcoantennas.com.au/site/p … ester-6ghz


#10

What kind of power supply are you using?

I had been using the PSU that came with the pi from element 14 - which is one of these http://au.element14.com/raspberry-pi-psu/rpi-psu-au-mk1/power-supply-raspberry-5v-1a-aus/dp/2254795

I have 2 spare pi’s so once those 3 PSU’s blew up i ordered 3 more from ebay. Those 3 have now blown up. Ive put on a ARLEC (cheap) surge protector like this one https://www.golights.com.au/arlec-2400-w-surge-protected-double-adaptor?gclid=CJzImIO_p9ICFUYFKgodykkI_w.

Since my next 3 PSU’s have blown up all i had sitting around was a iPhone charger and USB to micro USB lead. So, i’ve been using the iphone charger for the past 3 or 4 weeks, with the surge protector until now. The iphone charger has also blown up.

I’d bet if you checked your mains voltage with a good voltmeter, it’s over 250 Volts, npt the 230 Volt nominal – seeing that you’re in Australia

I’ll check on that. If anything i would expect our voltage to be more on the lower side. We are reasonably rural.

Is there any real ground connection from the coax or antenna mount to true ground? Like a ground rod or similar?

No, all i have is a SMA to BNC pigtail into a short BNC (2m) patch lead into the bottom of the antenna.

If the power supply dies but the Pi is intact, that sounds like the problem is on the mains side, not the Pi side. You might want to try something to condition the mains.

Yes, thats what has happened again. I was thinking about (and have bought) connecting the pi to a battery (via USB port) and then keeping the battery charged as i wanted to do a similar system and put some pi’s out in the outback.

Thanks

Haydn


#11

Hey Haydn,

Where is aus are you? I’m in Sydney’s west and haven’t had an issue with supplies blowing up.

The most obvious thing is it looks like the element14 ones are a bit underpowered … they are only a 1A output hence why you are losing so many.

The ones I use are from Wiltronics in Victoria, have a look here: https://wiltronics.com.au/product-category/raspberry-pi-power-supply/
They are a 2.5A output and haven’t missed a beat here.

Another source is here:http://www.altronics.com.au/p/m8820-raspberry-pi-micro-usb-5.1v-dc-2.5a-power-supply/ - albeit a bit dearer.

Hope this helps!

Cheers,

Andrew


#12

Looking at the specs of the element14 supply that Haydn posted - it’s grossly under-powered and running at its max output all the time I would guess. I’ll put money on that being the reason why he’s going through so many.

Andrew


#13

I’d bet if you checked your mains voltage with a good voltmeter, it’s over 250 Volts, npt the 230 Volt nominal – seeing that you’re in Australia

I have checked and the mains voltage is 250v

Where is aus are you? I’m in Sydney’s west and haven’t had an issue with supplies blowing up.

Hi Andrew we’re out near Cessnock Just west of Newcastle.

The most obvious thing is it looks like the element14 ones are a bit underpowered … they are only a 1A output hence why you are losing so many.

I’m only running a B+ and the pi website says:

Typically, the model B uses between 700-1000mA depending on what peripherals are connected … The maximum power the Raspberry Pi can use is 1 Amp. If you need to connect a USB device that will take the power requirements above 1 Amp, then you must connect it to an externally-powered USB hub.

I would have thought there shouldn’t be a problem with 1A PSU.


#14

The Pi Foundtion’s recommendation is a 1.8A PSU for B+.

Typcial consumption of the bare board is 330mA, the Pro Stick officially uses 300, a wifi dongle might use from 100 to 500mA, so it is possible that you are on or over the lmit.

I read somewhere that typcial chargers are not ideally suited to supply a Pi. They supply a steady flow to charge a device, whereas the power needs of a rPi are changing constantly. However, that was mentioned in connection with voltage drops, not PSU blowing up.


#15

2.5A now installed - back online. Will see what happens now!