Control Techniques Commander SK User Manual

Menu 2 Introduction Parameter x.00
Parameter
description format
Keypad and
display
CT Modbus
RTU
User
programming
CT Soft Menu 0
Advanced parameter
descriptions
36 Commander SK Advanced User Guide
www.controltechniques.com Issue Number: 2
Figure 9-9
Since the ramp rate is defined in s/100Hz (s/1000Hz when Pr 2.39 = 0) and the S ramp parameter is defined in s
2
/100Hz (s
2
/1000Hz when Pr 2.39 =
0), the time T for the 'curved' part of the S can be determined quite easily by dividing the two variables thus:
T = S ramp rate of change / Ramp rate
Enabling S ramp increases the total ramp time by the period T since an additional T/2 is added to each end of the ramp in producing the S.
This voltage is used as the level for standard ramp modes. If it is set too low the machine will coast to rest, and if it is set too high and no braking
resistor is used it may trip on OV. The minimum level should be greater than the voltage produced on the DC bus by the highest supply voltage.
Normally the DC bus voltage will be approximately the rms supply voltage x √2
If the output frequency does not decrease in 10 seconds after the drive has been given a stop command, the drive will disable. This can occur at low
speeds with long cables on a soft supply.
The acceleration rate is selected as follows.
0 Ramp rate selection by terminal input
1 to 8 Ramp rate defined by parameter number, i.e. 1 = Pr 2.11, 2 = Pr 2.12, etc.
9 Ramp rate selection by parameter Pr 1.50
When parameter Pr 2.10 is set to 0 the acceleration ramp rate selected depends on the state of bit parameters Pr 2.32 to Pr 2.34. These bits are for
control by digital inputs such that ramp rates can be selected by external control. The ramp rate selected depends on the binary code generated by
these bits as follows:
2.08 Standard ramp voltage
Coding
Bit SP FI DE Txt VM DP ND RA NC NV PT US RW BU PS
11 111
Range 0 to DC_VOLTAGE_SET_MAX V
Default
200V rating drive: 375
400V rating drive: EUR: 750, USA: 775
Update rate Background
2.09 Unused parameter
2.10 Acceleration rate selector
Coding
Bit SP FI DE Txt VM DP ND RA NC NV PT US RW BU PS
111
Range 0 to 9
Default 0
Update rate 5ms
t
Acceleration
Actual Speed
Programmed
ramp rate
TT
T/2 T/2 T/2T/2
S ramp
acceleration
ramp
Demanded Speed
NOTE

Control Techniques Commander SK Specifications

General

Brand	Control Techniques
Model	Commander SK
Category	Inverter
Language	English