Go to Post "When I joined the team, I was told that we'd be in the shop for six weeks. I STILL haven't seen a single boutique, and now they have me dumpster diving for robot parts! I quit!" - EricH [more]
Home
Go Back   Chief Delphi > Technical > Electrical
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Closed Thread
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 20-03-2012, 06:24
tilky's Avatar
tilky tilky is offline
Registered User
AKA: Ryan Thielke
FRC #3137
Team Role: Programmer
 
Join Date: Nov 2011
Rookie Year: 2011
Location: Connetquot
Posts: 188
tilky is an unknown quantity at this point
Analog Input Voltage Verification

I just want to verify to make sure that analog input sensors would return a signal of 5 volts maximum. We want to be able to test all of our things on sidecar and modules, because there has been some coding problems that don't make sense. if we take a multimeter and send 5 volts into the analog input locations on the module, we won't fry it right?
  #2   Spotlight this post!  
Unread 20-03-2012, 06:47
EricVanWyk EricVanWyk is offline
Registered User
no team
 
Join Date: Jan 2007
Rookie Year: 2000
Location: Boston
Posts: 1,597
EricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond repute
Send a message via AIM to EricVanWyk
Re: Analog Input Voltage Verification

There is a bit of confusion in your wording, so I'm hesitant to give a blanket "yes".

The analog input module (sitting on top of the cRIO) are able to safely measure 5V. In fact, they are able to measure slightly higher voltages as well - their maximum is not 5V.

Many analog sensors will return a voltage in the 0V to 5V range, but there are others that do not. What specific sensors are you using?

Multimeters measure voltage (and other electrical measurements like resistance and current), but they are not typically used to create a voltage.

The digital sidecar does not have any analog inputs. They do have digital inputs.
  #3   Spotlight this post!  
Unread 20-03-2012, 07:02
tilky's Avatar
tilky tilky is offline
Registered User
AKA: Ryan Thielke
FRC #3137
Team Role: Programmer
 
Join Date: Nov 2011
Rookie Year: 2011
Location: Connetquot
Posts: 188
tilky is an unknown quantity at this point
Re: Analog Input Voltage Verification

we aren't using any sensors (yet), but i noticed what might be a problem with the PWMs (it is an old sidecar from a few years ago). While we were planning on testing those, i thought it was a good idea to test everything else. Since it is an input, i wanted to make sure we can safely put 5 volts into it and see if we get any reading on the programming side of it. Sorry about the multimeter confusion, thought you would be able to send out 5 V on the resistance setting (i am programmer, not electrical but i thought this post would be more appropriate under the electrical, and not so much under programming)
  #4   Spotlight this post!  
Unread 20-03-2012, 07:41
EricVanWyk EricVanWyk is offline
Registered User
no team
 
Join Date: Jan 2007
Rookie Year: 2000
Location: Boston
Posts: 1,597
EricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond repute
Send a message via AIM to EricVanWyk
Re: Analog Input Voltage Verification

You are correct that a multimeter does produce a voltage when it is put in resistance mode, but this voltage is very small.

The PWM ports are outputs on the sidecar. Do not drive a voltage into them.
  #5   Spotlight this post!  
Unread 20-03-2012, 07:47
tilky's Avatar
tilky tilky is offline
Registered User
AKA: Ryan Thielke
FRC #3137
Team Role: Programmer
 
Join Date: Nov 2011
Rookie Year: 2011
Location: Connetquot
Posts: 188
tilky is an unknown quantity at this point
Re: Analog Input Voltage Verification

no the PWM's i know how to test (run a motor from them via jaguar). so if we find a 5V .25 A supply we can safely send it into the signal terminal on the Analog In?
  #6   Spotlight this post!  
Unread 20-03-2012, 08:14
EricVanWyk EricVanWyk is offline
Registered User
no team
 
Join Date: Jan 2007
Rookie Year: 2000
Location: Boston
Posts: 1,597
EricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond reputeEricVanWyk has a reputation beyond repute
Send a message via AIM to EricVanWyk
Re: Analog Input Voltage Verification

Yes. You can apply 5V to the analog inputs on top of the cRIO to test them. Your supply does not need to be able to provide 0.25A, the inputs will draw very little current (on the order of a million times less than .25A).
  #7   Spotlight this post!  
Unread 20-03-2012, 08:19
Alan Anderson's Avatar
Alan Anderson Alan Anderson is offline
Software Architect
FRC #0045 (TechnoKats)
Team Role: Mentor
 
Join Date: Feb 2004
Rookie Year: 2004
Location: Kokomo, Indiana
Posts: 9,113
Alan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond reputeAlan Anderson has a reputation beyond repute
Re: Analog Input Voltage Verification

There is a 5V supply built in to the Analog Breakout. If all you want to do is make sure your program can tell the difference between 5V and 0V on the analog input pin, that's easy. Each input channel's three-pin connector contains both 5V and 0V. All you would need is a switch to connect the signal pin to either the center 5V pin or the opposite 0V pin.

The exact same switch setup can test the digital inputs on the Digital Sidecar.
Closed Thread


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 19:44.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi