Why do pcb's (nic's and power supply's) blow?

[cmpelser]

Has anyone got some sort of letter or formal discription of why a certain pcb will blow or pop etc. (esd, power dips,spikes or lightning)
We need to give it to customers for insurance claims etc.
Thanks guys!

[Absurd]

THEY NEEDED THE MONEY!! hey ohhhhhhhhhh

[bsm2]

lighting

sounds like you customer was hit by lighting
if so nic card and power supply pcb's and fax card will take the first hit.

if power company had a transformer blow same problems

[Jules Winfield]

Has anyone got some sort of letter or formal discription of why a certain pcb will blow or pop etc. (esd, power dips,spikes or lightning)
We need to give it to customers for insurance claims etc.
Thanks guys!

It's usually a good idea to include surge suppressors with all contract machines out in the field and to make sure it says in the contract that PCBs will not be covered if the machine is not plugged in to the included surge suppressor.

[Mike Harden]

Have you check to make sure the ground is connected in the outlet take a tested and plug it in and see if you get the correct indication on the tester that you plug in is wired correctly. If it is a Mita product they lose PBA all the time they use 10% componets instead of 5% which is the first mistake of the Mita. Mitas 4850 would lose High Voltage Power Supply for no reason. If it is toner sensors stop vacuming out the developer that will blow out the a lot of PBA if its still connected to the machine and the next area are you wearing a static ground strap when you work on the electronics? These are just a few of the items your machine manufacture will point out as area that cause PBA to fail and eliminate their liablity be sure to have your answers ready before you ask for documentation.

[lamboalex]

from what ive seen power spikes are a major cause. also power outages can kill machine bds when the power kicks on again

[cmpelser]

No, I know why the board blew...
This particular one blew dew to ESD! (cold dry winter - ie. no lightning)
Now what the customer wants is a report of some kind.
I am looking for a well written explination that the customer is going to understand.
Please guys, I'm not that great at creative writing, and I can't find a "good" discription on the net.

[aragul]

PC ComputerNotes - ESD
"If the discharge was felt, it was probably more than 2000 volts. If you heard it, then it could have been between 3000 - 5000 volts. If you actually saw a small blue spark, it was more than likely in excess of 10,000 volts."
"The ICs (Integrated Circuit chips) on the various circuit boards in your computer use between 2 - 5 volts. They can be damaged by less than 200 volts. Some may be damaged by as little as 30 volts. This means that ESD can cause damage to the various components inside your computer and you won't feel it, hear it, or see it. In fact, the discharge voltage could be 1000 times less than what the human body can feel!"

Electrostatic discharge - Wikipedia, the free encyclopedia
"ESD is a serious issue in solid state electronics, such as integrated circuits. Integrated circuits are made from semiconductor materials such as silicon and insulating materials such as silicon dioxide. Either of these materials can suffer permanent damage when subjected to high voltages, as a result there are now a number of antistatic devices that help prevent static build up."

I don't know if I trust the information on the first link since the page looks like a sales scam site from 1996, but it matches up with what I skimmed from wikipedia. In short, ESD kills PCBs because the board materials aren't designed to withstand the high voltages from an ESD.

[tech07]

For insurance purposes

In the past I just usually write an invoice and specifically note on it that it was caused by lightning, storm, water, etc. A repair receipt with company name usually will suffice. Be specific in writing as to the reason on the invoice.