<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
Hi,<br>
<br>
We have been using EtherCAT master 1.5.2 for about two years. We
have successfully implemented 4 machines. Each has 5 Kollmorgen AKD
servo drives and some Beckhoff IO modules.<br>
Now we are implementing a new machine. On this machine we usually
get the following messages: <br>
...<br>
"system2count() error: system_time_base less than system time
(system_time_base: -58905492552780, time:680659495658"<br>
"system2count() error: system_time_base less than system time
(system_time_base: -58905492552858, time:680660495658"<br>
"system2count() error: system_time_base less than system time
(system_time_base: -58905492552936, time:680661495658"<br>
"system2count() error: system_time_base less than system time
(system_time_base: -58905492553014, time:680662495658"<br>
...<br>
<br>
We implemented our system based on the <b>rtai_rtdm_dc</b> example.
Only main difference is, we use kernel modules with RTAI instead of
LXRT user mod.<br>
We are using "cyclic positon" (8) mode with distributed clock. <br>
We choose the first DC capable device as the reference clock by
calling <b>ecrt_master_select_reference_clock(master, 0);<br>
</b>The first node on the bus is a AKD servo drive.<br>
<br>
The error occurs from the startup and not disappear until we reboot
the PC and the drives. <br>
When the error occurs, it seems sometimes drives can't update the
new position reference. Therefore, if it is moving, it tries to stop
for one sample and continues to the new reference at the next
sample. <br>
This causes a loud "knock" sound on the machine.<br>
<br>
We didn't get this message with previous 4 machines. <br>
We tried different FW versions of the AKD drives. Also tried to
change the bus node order of the drives. But nothing changed.<br>
Do you know what can be the cause for this message? How can we fix
the problem?<br>
<br>
Best regards,<br>
Oguz.<br>
<br>
<div class="moz-signature">-- <br>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<title></title>
<br>
<pre class="moz-signature" cols="72">Oguz Dilmac
ARGE Bolumu
Bilko AS, R&D Department
====================================
Perpa Ticaret Merkezi B Blok Kat 13 Nr. 2568
TR-34384 Okmeydani Istanbul Turkey
Tel : +90 212 220 07 40 Fax : +90 212 210 47 01
e-mail : <a class="moz-txt-link-abbreviated" href="mailto:odilmac@bilko-automation.com">odilmac@bilko-automation.com</a>
web site : <a class="moz-txt-link-freetext" href="http://www.bilko-automation.com">http://www.bilko-automation.com</a>
</pre>
</div>
</body>
</html>