Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
03/31/12 22:46
Read: times


 		 #186958 - leakage effects..
Responding to: ???'s previous message
Raj Nambiar said:
UPS is ours. We don't find any noticeable spikes at the serial port side. Serial port of the UPS, is also opto isolated from the other part.

Does your UPS have a ground pin ?

Take an AC meter and measure the AC voltage, and AC current between the 'nominal ground' pins.

Connecting two powered 'large boxes', after power-up, with an electronics comms link is asking your link to do two things.

'Isolation' can still deliver significant leakage effects, and if the grounds float part even tens of volts, that represents a large spike at the instant you connect.
Ideally, that Ground-float-correction current path, should NOT include any electronics.


List of 36 messages in thread
TopicAuthorDate
FTDI F232RL Noise issues            01/01/70 00:00      
   GND,cables            01/01/70 00:00      
      of this is it, then            01/01/70 00:00      
   leakage effects..            01/01/70 00:00      
      Thanks for the comments..            01/01/70 00:00      
         changing the serial port data....            01/01/70 00:00      
         cable, bought off the shelf            01/01/70 00:00      
            Test standard solutions            01/01/70 00:00      
               Options..            01/01/70 00:00      
                  VCP /D2X            01/01/70 00:00      
                     Problem exists with both drivers            01/01/70 00:00      
                  Aten serial to USB cable uses a FTDI chip            01/01/70 00:00      
   FTDI chip ESD sensitivity            01/01/70 00:00      
      Thanks Oliver...            01/01/70 00:00      
         Zeners are slow            01/01/70 00:00      
         show Your circuit            01/01/70 00:00      
            F232 is USB powered but.. + circuit            01/01/70 00:00      
         USB Isolator Chips            01/01/70 00:00      
            Isolators            01/01/70 00:00      
         Better than zeners            01/01/70 00:00      
            just a thought            01/01/70 00:00      
               Layout            01/01/70 00:00      
                  VCP/Direct drivers            01/01/70 00:00      
                  Layout attached            01/01/70 00:00      
                     It's a high speed circuit !!!!            01/01/70 00:00      
                        Totally 100% Agreed            01/01/70 00:00      
                           the trouble with schematics ....            01/01/70 00:00      
                              Bandwidth limitation            01/01/70 00:00      
   22 ohms between serial port ground and FT232 ground helps...            01/01/70 00:00      
      of course it does            01/01/70 00:00      
         Erik,            01/01/70 00:00      
            Links please            01/01/70 00:00      
               Link...            01/01/70 00:00      
                  Solved            01/01/70 00:00      
                     Magnetics            01/01/70 00:00      
                        Ethernet input is connected to serial port ground            01/01/70 00:00      

Back to Subject List