PCB

mcgyvr

Joined Oct 15, 2009
5,394
What specifically does "covered" mean here?
Typically the board house will do an "e-test (electrical test)" with a bed of nails to ensure all connections on your PCB match the netlist.
 

Thread Starter

asd1234

Joined Jan 20, 2016
5
By covered i mean it has foam all over it, and so no components nothing can be seen or tested. So how is electrical tests done? Any way to check the PCB with only one end?
 

mcgyvr

Joined Oct 15, 2009
5,394
foam? maybe you mean conformal coating?
Why is it covered?
What are you trying to test?
Why do you need to test it?
What do you have access to?
What does only one end mean? maybe you mean one side as in the top (where all the components are) is covered in something and the bottom side is still accessible?
Do you have a picture of the board? (both sides)

If you want decent answers you need to provide sufficient/clear details.
 

GopherT

Joined Nov 23, 2012
8,009
By covered i mean it has foam all over it, and so no components nothing can be seen or tested. So how is electrical tests done? Any way to check the PCB with only one end?
PCBs for an MRI are likely coated to prevent the metal parts from vibrating in the magnetic field and causing distorting in the final image, or, they are covered in case anything comes loose so they don't fly out and stick to the magnet. (Remember, the docs always checks the eyes of machinists and mechanics for metal fragments because the magnetic field can rip them out in a more dramatic fashion than they were inserted.

A board like this will need (1) self-test circuitry to make sure everything works or (2) a technician with a device that the board can be plugged into for testing, or (3), simply replace the board

Check the software of the MRI. If you can't see a self-test option (or self-test log) it is likely done during startup and the user has no control. On the other hand, if you can afford to buy and maintain an MRI, then the manufacturer generally believes you can afforded to replace a damaged board.
 

Thread Starter

asd1234

Joined Jan 20, 2016
5
Its tested and given to us, but i am an intern and i need to find a way in which i can test the pcb. The pcb has one wire sort of thing coming out of it, and using that wire i need to find a way to test that PCB.

Also can frequency be given(applied) to a PCB?
 

GopherT

Joined Nov 23, 2012
8,009
Its tested and given to us, but i am an intern and i need to find a way in which i can test the pcb. The pcb has one wire sort of thing coming out of it, and using that wire i need to find a way to test that PCB.

Also can frequency be given(applied) to a PCB?
What did the manufacturer tell you when you called their technical support team with this question?
 

Dr.killjoy

Joined Apr 28, 2013
1,196
You would need a full schematic and be able to simulate as if the pcb was in the machine in order to test it..Basic tests could be done but don't test the whole circuit..
 

tindel

Joined Sep 16, 2012
936
Its tested and given to us, but i am an intern and i need to find a way in which i can test the pcb.
I am about to go off on you so if you don't want to hear it - quit reading now.

[rant on]
What the HELL are you doing asking these questions on a forum if you're an intern? You're an intern for crying out loud, and your education is just beginning (i.e. you currently have almost NO value to your employer - or anyone else for that matter)! Go ask the boss, or a co-worker, or someone who may have actually tested something similar or maybe even have some prior experience with MRI electronics. You're asking a bunch of forum junkies (as good, willing, and able, as they might be) for advise on a forum! You are there to learn. Let them see you learn! Research is certainly part of learning... but the boss needs to see you learn - not some forum strangers! Your job might depend on it!

The boss hired you for exactly two reasons - 1) you're super cheap labor - 2) he/she sees your potential, but wants to find out more about you before offering you good money to do something that is important to them and the company. 9 times out of 10 the things I've seen interns do - the result off the project hasn't mattered. The result is the boss knowing if you are going to work out long term or not. He/she only knows that by you asking him or another employee the right questions, at the right time, performing well, and showing that you can make the company the only thing that matters.... money.
[/rant off]
 

mcgyvr

Joined Oct 15, 2009
5,394
Its tested and given to us, but i am an intern and i need to find a way in which i can test the pcb. The pcb has one wire sort of thing coming out of it, and using that wire i need to find a way to test that PCB.

Also can frequency be given(applied) to a PCB?
To test a PCB assembly you create some sort of test fixture that makes contact with all necessary connectors/test points and tests the assembly as thoroughly as possible to ensure all functions work as they should.
You apply whatever "signals" are necessary to properly test the assembly.. That may be analog signals or digital signals or frequencies or whatever the device is meant to accept and function with.
Depending on the device the test fixture could be very simple to very complex and expensive.
Obviously the board must connect to something somehow so your test fixture would connect in the same way and simulate whatever this PCB assembly is connected to in the final product..

We can't possibly offer any more information to you as you have provided NO details or specifics that would allow us to offer anything but a totally random guess..

In the future if you want real answers to your questions you are going to need to get much better at providing details.
 

recklessrog

Joined May 23, 2013
985
If you refer to my earlier post #2, the question was answered!
I have always failed to understand how it is that some people think we are Psychic "seers"
and have supernatural powers that enable us to instantly know the ins and outs of "the bit that connects to the thingy with another bit on the end"

Please, If you want help with something, first of all, try and solve it yourself logically, then prepare a detailed description of what it is, what you have already done, and include a schematic or picture if possible.
Then, you are much more likely to get help from the more experienced on here.
 
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