AB Quality Allen-Bradley 1394 User Manual page 147

[Droop]
This parameter is also referred to as "static gain."
It effectively acts as a very slow discharge of the
velocity loop integrator and has two uses:
• As a component of an external position loop
system, setting this parameter to a higher, non-
zero value will eliminate servo hunting due to
load stick/slip friction effects.
• As a deliberate "velocity droop" (secondary
drives only) in multiple-motor systems where
each drive axis is configured as a velocity loop
and the motors are mechanically coupled
together. Use of higher non-zero droop in this
case promotes load sharing.This parameter
selects the torque command source within the
drive. When operating the drive in velocity
mode, set to Velocity Mode 1 (#0). When
operating in torque mode (using S Class), set
to A/D Torque Block (#4).
This parameter selects the torque command
source within the drive. When operating the drive
in velocity mode, set to Velocity Mode 1 (#0).
When operating in torque mode (using S Class),
set to A/D Torque Block (#4).
The droop scaling is defined as that specified
droop in output rpm (i.e., velocity error) that will
result in 100% rated torque being applied by the
motor in reaction. This parameter only has effect
if [Intg Gain Ki] is not zero.
For Example: Speed regulation of 0 to 0.05%
maximum depending on optimization of system
performance settings. 3000 rpm, 0.05% = 1.5
rpm tolerance.
[Enabled Days]
Displays the number of days that the drive has
been enabled.
[Enabled Minutes]
Displays the number of minutes that the drive has
presently been enabled.
[Fdbk Pole Cnt]
The number of electrical poles on the resolver.
Note: Before making modifications to Mtr Data
parameters, [Motor Type] must be set to "custom
motor".
Configuring Your 1394 Analog Servo System
Parameter Numbers
Parameter Group
Display Units
Parameter Type
Change While Running
Linkable
Minimum Value
Maximum Value
Default Value
Parameter Numbers
Parameter Group
Display Units
Parameter Type
Linkable
Parameter Numbers
Parameter Group
Display Units
Parameter Type
Linkable
Parameter Numbers
Parameter Group
Display Units
Parameter Type
Change While Running
Linkable
Minimum Value
Maximum Value
Default Value
380, 381, 382, 383
Vel Loop Data
rpm
Read/Write
Yes
No
0.0 rpm (No Droop)
15.6 rpm
1.0 rpm
93
Linear List
None
Read Only
No
92
Linear List
None
Read Only
No
400
Mtr Data
None
Read/Write
No
No
2
8
This is determined by the motor catalog number.
8-11
Publication 1394-5.0 — May 2000