tecan cavro xlp 6000 Operating Manual page 66

3 - Software Communication
Operating Commands
3.5.3
3 - 34
<n>
Parameter
Command Value
D 0-6000
0-48000
0-48000
For example:
The syringe plunger is at position 3000. [D300] will move the plunger up 300
increments to an absolute position of 2700.
The [D] command will return error 3 (invalid operand) if the final plunger
position would be less than 0.
d <n> Relative Dispense (Not Busy)
This is the same as the [D] command, except that the status bit of the reply
string indicates that the pump is not busy..
Set Commands (Speed and Acceleration)
Set commands are used to control the speed of the plunger. Plunger movement is
divided into three phases:
Ramping Up. Plunger movement begins with the start speed and accelerates
with the programmed slope to the constant or top speed.
Constant or Top Speed. The plunger moves at the constant or top speed.
Plunger speed can be programmed in Hz (half-increments/second) or in
preprogrammed Set Speeds. The actual time the plunger travels is dependent
on the ramping up and down. If the plunger move is short, it may never reach
top speed.
Ramping Down. The plunger will decelerate based on the programmed
slope. To enhance fluid breakoff, the Cutoff command ([c]) can be used to
define the end speed of the plunger just before it stops.
Note: The Cutoff command is only active in a dispense move. During aspiration
the move will end at the start speed [v].
For each plunger move, the firmware calculates how many increments the
plunger must travel during each phase in order to move the total number of
increments commanded. If the plunger is moving at a rate less than 900 Hz, the
pump automatically microsteps to reduce the pulsation.
The top speed can be changed on the fly (while the plunger is moving) using the
[v] command, providing the top speed is less than or equal to the start speed.
Ramps are not included in on-the-fly speed changes; therefore, large speed
changes (100 Hz to 1000 Hz) are not recommended.
Cavro® XLP 6000 Modular Syringe Pump Operating Manual, 734237-C, en
Description
Relative position in half increments (N=0)
Relative position in microsteps (N=1)
Relative position in microsteps (N=2)