NI Home
Cart Cart | Help
Hello Events Academic NI Developer Zone Support Solutions Products & Services Contact NI MyNI
You are here: 
 NI Home > NI Developer Zone > NI Discussion Forums

Multifunction DAQ

turn on suggestions Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Reply
Topic Options
Member Exedore
Member
Exedore
Posts: 3
0 Kudos

PCI6111 card started to give a higher signal than expected

Options

‎08-03-2012 02:28 PM

hello, we have an axopatch 200b conected to a BNC 2090 block and a PCI 6111, and we started to realice that the signal noice we detect in the computer is higher than expected, i.e. when we use the test dummy circuit for the axopatch the signal should be 5V but we see 7V instead. This problem occurs randomly, some days is 5V and suddenly is 7V... and later is 5V again...

does somebody have any suggestion?

thank you in advance

 

Message 1 of 5 (178 Views)
 
Reply
Active Participant P@Anand
Active Participant
P@Anand
Posts: 1,618
0 Kudos

Re: PCI6111 card started to give a higher signal than expected

Options

‎08-04-2012 01:40 AM

Exedore wrote:

hello, we have an axopatch 200b conected to a BNC 2090 block and a PCI 6111, and we started to realice that the signal noice we detect in the computer is higher than expected, i.e. when we use the test dummy circuit for the axopatch the signal should be 5V but we see 7V instead. This problem occurs randomly, some days is 5V and suddenly is 7V... and later is 5V again...

does somebody have any suggestion?

thank you in advance

 

What is the dummy circuit you use what is the output range of it?. Are you sure the output of the dummy circuit is 5V constant always?. If not Hook up a DMM with the same output that is going to the PCI card and see what is the value actually coming. I don't see anything with the card.

-----

I don't believe in Hard work. I love my work :smileyhappy:
Message 2 of 5 (173 Views)
 
Reply
Member Exedore
Member
Exedore
Posts: 3
0 Kudos

Re: PCI6111 card started to give a higher signal than expected

[ Edited ]
Options

‎08-05-2012 09:35 PM - edited ‎08-05-2012 09:37 PM

Hello, we used the dummy which came with the axopatch and made the test explained in the user manual (Chapter 3 pages 11-13), i will ask to our technician about your questions. I´m pretty sure the problem is in the NI because i split the signal from the amplifier and connected one cable to the BNC connector linked to the PCI6111 and the other one to an oscilloscope and compared both signals. The signal from the computer with the NI interface was sometime 5V sometime 7V, while in the osciloscope was always about 5V.

 

Message 3 of 5 (164 Views)
 
Reply
Member Plínio
Member
Plínio
Posts: 57
0 Kudos

Re: PCI6111 card started to give a higher signal than expected

Options

‎08-08-2012 12:56 PM

One possible cause is a grounding issue, in these cases some measure values can show itself different than the expected value.

 

You can read more about this on this link

 

http://www.ni.com/white-paper/3344/en

 

Regards,

 

Plínio Costa

 

 

Plínio Costa
Application Engineering
National Instruments Brazil

Message 4 of 5 (148 Views)
 
Reply
Member Exedore
Member
Exedore
Posts: 3
0 Kudos

Re: PCI6111 card started to give a higher signal than expected

Options

‎08-09-2012 08:01 AM

thank you plínio i wil discuss this with our technician

regards

 

Message 5 of 5 (144 Views)
 
Reply
By using this web site, you accept the Terms of Use for this web site. Please read these Terms of Use carefully before using any part of this site. Please go here for information on ni.com's copyright infringement policy.
My Profile | Privacy | Legal | Contact NI © 2011 National Instruments Corporation. All rights reserved.    |    E-Mail this Page E-Mail this Page