nuDrive Accessory User Guide
24
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Stepper Motor Current
You can modify the current limit and current reduction settings by
changing the values of the current limit resistor (R
CL
) and current reduction
resistor (R
CR
) on the stepper driver’s P2 terminal block.
If your motor specifies the peak output current, then calculate the value of
R
CL
by
where R
CL
represents the current limit resistor value in ohms and I
peak
represents the peak output current.
If your motor specifies the output current as an RMS value, then calculate
the value of R
CL
by
where R
CL
represents the current limit resistor value in ohms and I
RMS
represents the output current as an RMS value.
Calculate the value for R
CR
by
where R
CR
represents the current reduction resistor value in ohms
,
R
CL
represents the current limit resistor value in ohms
,
and I
red
represents the
DC output current (in amps) when the nuDrive is operating in current
reduction mode.
Table 4 lists the RMS and peak currents for standard values of R
CL
(5% type 1/4 W resistors).
Warning
A current limit resistor (R
CL
) is always required to keep the drive in a safe
operating condition. Be sure to use a current limit resistor with a value no greater
than 2.0 k
Ω.
R
CL
I
peak
0.002
-------------
=
R
CL
I
RMS
0.001414
----------------------
=
R
CR
I
red
R
CL
×
0.002
R
CL
×
(
)
I
red
–
------------------------------------------------
=
Summary of Contents for nuDrive 2CF-001
Page 32: ......
