JVL MAC050 User Manual page 215

5.6 Expansion Mod. MAC00-FC2/FC4/FC41
If the received PDOs are transmitted faster than the internal processing time, an internal
queue overflow occurs (See emergency object). If the SYNC object interval is smaller that
the processing time of the active transmit PDOs, an internal queue overflow error occurs.
JVL A/S - User Manual - Integrated Servo Motors MAC050 - 4500 211