Applied Motion STM23R-2ND - Manual (Page 22)

22
STM23R Hardware Manual 920-0056C
5/5/2015
Step 6: Step Pulse Noise Filter
Just when you thought there couldn’t be any more to know about step signals, we present one more setting for
your consideration. Electrical noise can affect the STEP signal in a negative way, causing the drive to think that
one step pulse is two or more pulses. This results in extra motion and inaccurate motor
and load positioning. To combat this problem, the STM23R includes a digital noise filter
on the STEP and DIR inputs. The default factory setting of this filter is150 kHz, which
works well for most applications. This is set by moving switch 5 to the ON position.
However, as discussed in Step 4, if you are operating the STM23R at a high number
of steps/rev and at high motor speeds, you will be commanding the drive at step rates
above 150 kHz. In such cases, you should set switch 5 to the OFF position as shown
below.
Your maximum pulse rate will be the highest motor speed times the steps/rev. For example, 40 revs/second at
20,000 steps/rev is 40 x 20,000 = 800 kHz. Please consider this when deciding if you must increase the filter
frequency.
Self Test
If you are having trouble getting your motor to turn, you may want to try the built-in self test. Anytime switch 4
is moved to the ON position, the drive will automatically rotate the motor back and forth, two and a half turns
in each direction. This feature can be used to confirm that the motor is correctly wired, selected and otherwise
operational.
8
STEP CW/
STEP CCW
STEP/
DIR
8
5
150
KHZ
5
2.0
MHZ
4
ON
4
OFF
SELF TEST