Manual

Detailed Descriptions of ACL Commands 3-63
During the conversion from Calibrated Units to microsteps, the intermediate computation
results must be within the range -32768 through 32767 and the final results must be within
the travel limits. If either restriction is not met an error is logged and the position counters
are not changed.
SR [<rate>] Step Rate
The value <rate> specifies the step rate, or speed, to be used in subsequent AA, AR, MA,
MR, and MT commands, as well as Continuous Path motion, the GO TO ORIGIN vector,
and the FH backoff vectors. The value is in microsteps per second. Zero is treated as 1.
Specifiable values are in the range 1 through 65535, although under most conditions the
System cannot achieve 65535 microsteps per second. If a microstep is 0.001 inch the above
numbers correspond to 0.001 through 65.535 inches per second. If <rate> is higher than the
highest achievable speed, the System simply uses the highest speed it is capable of; see
below.
The step rate defaults to 10000 at power up and IN, and if <rate> is omitted from the SR
command. The default value 10000 itself can be changed via the PE command, so that the
System "wakes up" with the desired step rate at power up.
During a given arc, vector, or Continuous Path move the step rate increases smoothly from
zero to the specified value, at an acceleration rate determined by the AC command. Then
there is a constant-speed "slew" phase, and a deceleration phase. Short moves may never
reach the specified slew speed, since the entire move may be taken up by the acceleration
and deceleration phases.
Diagonal vectors are performed at the specified speed; i.e., the X and Y motors travel at the
appropriate speeds to make the diagonal speed equal to the specified value.
For arcs, the tangential speed (i.e. the speed along the path of the arc) will be the specified
value, but never higher than approximately 17000 microsteps per second. If the radius is
less than a certain value, the System automatically decreases the slew speed in order to limit
the radial acceleration; see the AC command.
If <rate> is higher than the highest achievable arc speed then single vectors are performed at
a higher speed than single arcs.
For a Continuous Path move, vectors are always performed at the same speed as arcs. This
speed can never exceed approximately 16000 microsteps per second, and may be further
limited by the smallest arc radius in the BC...EC sequence. See the BC command.
The maximum achievable step rate depends on the microstep factors (i.e. "resolution"). (For
more information, see the RE command.) At the default corresponding to RE 8.00, 8.00;
the approximate maximum speeds are as follows:
Vectors: Approx. 59000 microsteps/sec
Arcs: Approx. 17000 microsteps/sec
Continuous Path vectors and arcs: Approx. 16000 microsteps/sec