Parameter Ranges And Variable Maximums - Control Techniques Digitax ST Advanced User's Manual

Parameter Keypad and
structure display
4.1

Parameter ranges and variable maximums:

The two values provided define the minimum and maximum values for
the given parameter. In some cases the parameter range is variable and
dependant on either:
• other parameters,
• the drive rating,
• or a combination of these.
The values given in Table 4-1 are the variable maximums used in the
drive.
Table 4-1 Definition of parameter ranges & variable maximums
Maximum
SPEED_FREQ_MAX
[40000.0rpm]
SPEED_LIMIT_MAX
[40000.0rpm]
SPEED_MAX
[40000.0rpm]
DRIVE_CURRENT_MAX
[9999.99A]
AC_VOLTAGE_SET_MAX
[690V]
AC_VOLTAGE_MAX
[930V]
DC_VOLTAGE_SET_MAX
[1150V]
DC_VOLTAGE_MAX
[1190V]
MOTOR1_CURRENT_LIMIT_MAX
[1000.0%]
MOTOR2_CURRENT_LIMIT_MAX
[1000.0%]
16
Parameter description
Parameter x.00
format
Maximum speed reference
If Pr 1.08 = 0: SPEED_FREQ_MAX = Pr 1.06
If Pr 1.08 = 1: SPEED_FREQ_MAX is Pr 1.06 or – Pr 1.07 whichever is the largest
(If the second motor map is selected Pr 21.01 is used instead of Pr 1.06 and Pr 21.02 instead of Pr 1.07)
Maximum applied to speed reference limits
A maximum limit may be applied to the speed reference to prevent the nominal encoder frequency from
exceeding 500kHz. The maximum is defined by
SPEED_LIMIT_MAX (in rpm) = 500kHz x 60 / ELPR = 3.0 x 10
40,000 rpm.
ELPR is equivalent encoder lines per revolution and is the number of lines that would be produced by a
quadrature encoder.
Quadrature encoder ELPR = number of lines per revolution
F and D encoder ELPR = number of lines per revolution / 2
Resolver ELPR = resolution / 4
SINCOS encoder ELPR = number of sine waves per revolution
Serial comms encoder ELPR = resolution / 4
This maximum is defined by the device selected with the speed feedback selector (Pr 3.26) and the ELPR set
for the position feedback device.
Maximum speed
This maximum is used for some speed related parameters in menu 3. To allow headroom for overshoot etc. the
maximum speed is twice the maximum speed reference.
SPEED_MAX = 2 x SPEED_FREQ_MAX
Maximum drive current
The maximum drive current is the current at the over current trip level and is given by:
DRIVE_CURRENT_MAX = K
Maximum output voltage set-point
Defines the maximum motor voltage that can be selected.
200V drives: 240V, 400V drives: 480V
Maximum AC output voltage
This maximum has been chosen to allow for maximum AC voltage that can be produced by the drive including
quasi-square wave operation as follows:
AC_VOLTAGE_MAX = 0.78 x DC_VOLTAGE_MAX
200V drives: 325V, 400V drives: 650V
Maximum DC voltage set-point
200V rating drive: 0 to 400V, 400V rating drive: 0 to 800V
Maximum DC bus voltage
The maximum measurable DC bus voltage.
200V drives: 415V, 400V drives: 830V
Maximum current limit setting for motor map 1
The maximum current limit setting is the maximum applied to the current limit parameters in motor map 1.
Where:
[
Maximum current
Maximum
=
current limit
Motor rated current
The Maximum current is (1.75 x K
Motor rated current is given by Pr 5.07
Maximum current limit settings for motor map 2
This maximum current limit setting is the maximum applied to the current limit parameters in motor map 2.
The formulae for MOTOR2_CURRENT_LIMIT_MAX are the same for MOTOR1_CURRENT_LIMIT_MAX
except that Pr 5.07 is replaced with Pr 21.07 and Pr 5.10 is replaced with Pr 21.10.
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Definition
/ 0.45
C
]
x 100%
).
C
Serial comms Electronic
protocol nameplate
7
/ ELPR subject to an absolute maximum of
Digitax ST Advanced User Guide
Issue Number: 1
Performance