Quote:
Originally Posted by mbone206
Drive would periodically have lag and when idle, make pop corn sounding noise on its own (solenoids)?
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Depending on what you mean by popcorn noises, it could be:
- Circuit Breakers popping. Watch the PD for red flashing lights.
- Spike Relays firing. Watch their LEDs.
- Solenoids firing. Watch the LEDs on their controller (solenoid breakout or Spike), or feel them.
- Static discharge. This is more of a crackly noise.
Quote:
Originally Posted by mbone206
* Grounding: What is best way to Ground, here many opinions in links.. and what is legal.. Ground motors to chassis?
Need to isolate supply ground and Rio from chassis?
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YES. You must isolate the cRIO from the chassis per R38. If your motors are are experience case faults, they too must be isolated from the chassis.
Quote:
Originally Posted by mbone206
2) Caps?: Does anyone use capacitors across motor terminals? Has this helped? What value do you use?
Power Supply: Does anyone ad addition caps on power supply line? I do not have an Oscope to see
noise on supply line possibly getting on Rio supply, but thought this could cause sporadic problems?
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Capacitors are unlikely to help with the types of issues you are describing. Teams occasionally place small caps across motors to clean up with noise couple into their analog sensors. I wouldn't add capacitance to the cRIO's supply, it is already sufficiently bypassed.
As a side note, sometimes adding capacitance to a supply can make it unstable, as it tweaks the control loop unexpectedly. Current Gen PDs don't have this issue, but a 2009 PD might not respond well if you added e.g. an a large electrolytic cap near the 24V output. Unfortunately, usfirst.org has the old schematics up for some unknown reason.