6-4 Troubleshooting MN1903
Symptom Check
Motorruns unc ontrollably
whencont roller is switched
onand serv o loop gains are
appliedor whena move is
setin pr ogress. Motorthen
stops after a short time.
Check that the axis’ corresponding encoder and demand
signals are connected to the same axes of motion. Check
thedemand to the driv e is connected with the correct
polarity.
Check that for a positive demand signal, a positive increase
inaxis positionis seen. TheMintMT ENCODERMODE
keyword can be used to change encoder input direction.
TheMintMT DACMODE keywor d can be used to reverse DAC
outputpolarity.
Check that the maximum following error is set to a
reasonablev alue. For setting up purposes, following error
detectionmay bedisabled by setting FOLERRORMODE = 0.
Motoris under c ontrol, but
vibrates or overshoots
duringa move.
Servo loop gains may be set incorrectly. Seesections 5.4.2
to5.6.
Motoris under c ontrol, but
whenmoved t o a position
andthen back tothe start it
doesnot r eturn to the same
position.
Usingan os cilloscope at the breakout module connectors,
check:
Hallencoder c hannels are clear signals and free from
electrical noise;
Htheyare c orrectly wired to the controller;
Hwhenthe motor tur ns, the two square wave signals are
90degrees out of phase.Also check the complement
signals.
Ensure that the encoder lead uses shielded twisted pair
cableand that the s hield is attached to the shield connection
onlyat the br eakout module end.
Verifythat the break out module and drive are correctly
groundedto a c ommon earth point.