Emerson unidrive sp, User Manual

Page: 39 / 420

Parameter
structure
Keypad and
display
Parameter
x.00
Parameter
description format
Advanced parameter
descriptions
Macros
Serial comms
protocol
Electronic
nameplate
Performance RFC mode Menu 1
Unidrive SP Advanced User Guide
39
Issue Number: 10 www.controltechniques.com
Three skip references are available to prevent continuous operation at a speed that would cause mechanical resonance. When a skip reference
parameter is set to 0 that filter is disabled. The skip reference band parameters define the frequency or speed range either side of the programmed
skip reference, over which references are rejected. The actual reject band is therefore twice that programmed in these parameters, the skip reference
parameters defining the centre of the band. When the selected reference is within a band the lower limit of the band is passed through to the ramps
such that reference is always less than demanded.
This parameter indicates that the selected reference is within one of the skip reference zones such that the motor speed is not as demanded.
Although most parameters can be controlled from analog inputs, these two parameters are a special case in that if an analog input is directed to one
of these parameters, the scan rate of that analog input is increased to 250
μ
s as long as:
1. The reference must be derived via Pr 1.36 or Pr 1.37
2. The analog inputs must be in voltage mode with zero offset
3. Bipolar mode must be used or unipolar mode with the minimum speed (Pr
1.07 ) set to zero
4. No skip bands are enabled, i.e. Pr 1.29 , Pr 1.31 and Pr 1.33 must be zero.
5. The jog and velocity feed-forward references must not be enabled.
These are special parameters when a non-bit type quantity uses these parameters as a destination (not just from analog inputs). The scaling and
limiting applied is as described with Pr
1.08 on page 33.
See Pr 1.09 on page 34.
1.30 Skip reference band 1
1.32 Skip reference band 2
1.34 Skip reference band 3
Drive modes Open-loop, Closed-loop vector, Servo
Coding
Bit SP FI DE Txt VM DP ND RA NC NV PT US RW BU PS
1 1 1 1
Closed-loop vector and servo DP = 0
Range
Open-loop
Closed-loop vector, Servo 0.0 to 25.0 Hz
0 to 250 rpm
Default
Open-loop
Closed-loop vector, Servo 0.5
5
Update rate Background read
1.35 Reference in rejection zone
Drive modes Open-loop, Closed-loop vector, Servo
Coding
Bit SP FI DE Txt VM DP ND RA NC NV PT US RW BU PS
1 1 1 1
Update rate 4ms write
1.36 Analog reference 1
1.37 Analog reference 2
Drive modes Open-loop, Closed-loop vector, Servo
Coding
Bit SP FI DE Txt VM DP ND RA NC NV PT US RW BU PS
1 1 1 1
Range Open-loop, Closed-loop vector, Servo ±SPEED_FREQ_MAX Hz/rpm
Default Open-loop, Closed-loop vector, Servo 0
Update rate 4ms write
1.38 Percentage trim
Drive modes Open-loop, Closed-loop vector, Servo
Coding
Bit SP FI DE Txt VM DP ND RA NC NV PT US RW BU PS
2 1 1
Range Open-loop Closed-loop vector, Servo ±100.00 %
Default Open-loop Closed-loop vector, Servo 0.00
Update rate 4ms read