# RTDE Connection not working

**URL:** <https://forum.universal-robots.com/t/rtde-connection-not-working/1999>\
**Category:** Robot Communication\
**Created:** [May 18, 2018, 11:14am UTC](https://forum.universal-robots.com/t/rtde-connection-not-working/1999 "2018-05-18T11:14:50Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![anon94763411](https://avatars.discourse-cdn.com/v4/letter/a/3e96dc/32.png) [@anon94763411](https://forum.universal-robots.com/u/anon94763411)\
**Post date:** [May 18, 2018, 11:14am UTC](https://forum.universal-robots.com/t/rtde-connection-not-working/1999/1 "2018-05-18T11:14:50Z")

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Hello,  
I am working on RTDE python script for data logging. It is working fine but sometimes it will give error “RTDE disconnected” even I am able to ping the robot IP

The error is like this  
INFO:root:RTDE disconnected  
ERROR:root:Unable to send: not connected to Robot  
Traceback (most recent call last):  
File “UR5.py”, line 87, in   
if not con.send\_output\_setup(output\_names, output\_types, frequency = args.frequency):  
File “/home/alstrut/Documents/RTDE/rtde/rtde.py”, line 126, in send\_output\_setup  
if len(types)!=0 and not self.\_\_list\_equals(result.types, types):  
AttributeError: ‘NoneType’ object has no attribute ‘types’

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**Author:** ![ajp](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/ajp/32/471_2.png) [@ajp](https://forum.universal-robots.com/u/ajp)\
**Post date:** [May 22, 2018, 5:32am UTC](https://forum.universal-robots.com/t/rtde-connection-not-working/1999/2 "2018-05-22T05:32:37Z")

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Hi @anon94763411,

So this looks like the connection sometimes fails to start rather than failing halfway through after being successfully established?

This could potentially be related to a network issue … even though you can ping the robot the connection may be unstable. Are you connecting via wifi? Perhaps try a cable?

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<div class="post-metadata">

**Author:** ![anon94763411](https://avatars.discourse-cdn.com/v4/letter/a/3e96dc/32.png) [@anon94763411](https://forum.universal-robots.com/u/anon94763411)\
**Post date:** [May 22, 2018, 1:00pm UTC](https://forum.universal-robots.com/t/rtde-connection-not-working/1999/3 "2018-05-22T13:00:22Z")

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Thank you for your quick response.  
Yes the problem you mentioned is same we are facing.  
Yes I am connecting with Ethernet cable. same code I tried with other UR and working fine. Sometimes it works sometimes it will not.  
Is this a problem related to Ethernet port .

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<div class="post-metadata">

**Author:** ![inu](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/inu/32/732_2.png) [@inu](https://forum.universal-robots.com/u/inu)\
**Post date:** [May 22, 2018, 1:23pm UTC](https://forum.universal-robots.com/t/rtde-connection-not-working/1999/4 "2018-05-22T13:23:22Z")

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It could be related to the port, try connecting the Ethernet cable directly to the motherboard instead. This will bypass the extension that goes to the bottom of the control box which may be causing an issue.

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<div class="post-metadata">

**Author:** ![anon94763411](https://avatars.discourse-cdn.com/v4/letter/a/3e96dc/32.png) [@anon94763411](https://forum.universal-robots.com/u/anon94763411)\
**Post date:** [May 22, 2018, 4:00pm UTC](https://forum.universal-robots.com/t/rtde-connection-not-working/1999/5 "2018-05-22T16:00:33Z")

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Thank you  
I will try this and update soon

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<div class="post-metadata">

**Author:** ![anon94763411](https://avatars.discourse-cdn.com/v4/letter/a/3e96dc/32.png) [@anon94763411](https://forum.universal-robots.com/u/anon94763411)\
**Post date:** [May 24, 2018, 6:10am UTC](https://forum.universal-robots.com/t/rtde-connection-not-working/1999/6 "2018-05-24T06:10:54Z")

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Hello,  
I directly connected with motherboard. For one day it worked fine, again I come across same error.