Menu 2 − Frequency Ramps

Mode: RFC‑A


Parameter02.001  Post Ramp Reference
Short descriptionDisplays the output of the ramp system
ModeRFC‑A
Minimum−VM_SPEED_FREQ_REFMaximumVM_SPEED_FREQ_REF
Default UnitsHz
Type32 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places2
CodingRO, VM, ND, NC, PT

The Post Ramp Reference (02.001) can be combined with the Hard Frequency Reference (03.022) to give the final frequency reference at the input to the frequency controller (see Menu 03). If the Hard Frequency Reference (03.022) is used alone to give the final frequency reference, and the ramp output is not required, then the ramp output can be disconnected by setting Disable Ramp Output (02.005) = 1. This ensures that the reference and ramp systems do not affect the final frequency reference.


Parameter02.002  Ramp Enable
Short descriptionSet to 1 to enable the ramp system
ModeRFC‑A
Minimum0Maximum1
Default1Units 
Type1 Bit User SaveUpdate RateBackground
Display FormatStandardDecimal Places0
CodingRW, BU

If Ramp Enable (02.002) = 1 then the ramp system is present between the Pre-ramp Reference (01.003) and the Post Ramp Reference (02.001). If Ramp Enable (02.002) = 0 then any changes in the Pre-ramp Reference (01.003) are reflected immediately in the Post Ramp Reference (02.001).


Parameter02.003  Ramp Hold
Short descriptionSet to 1 to hold the ramp system at its present value
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit User SaveUpdate Rate1ms
Display FormatStandardDecimal Places0
CodingRW

If Ramp Hold (02.003) = 0 the ramp system functions normally. If Ramp Hold (02.003) is set to 1 and S Ramp Enable (02.006) = 0 the ramp system output is held at its current level. If Ramp Hold (02.003) is subsequently set to 0 the ramp system output is released and continues to operate normally. If S Ramp Enable (02.006) = 1 when Ramp Hold (02.003) is set to 1 the acceleration will ramp towards zero and the frequency will change in an S curve towards a constant frequency. If a drive stop is requested (i.e. Reference On (01.011) = 0) the ramp hold function is disabled.


Parameter02.004  Ramp Mode Select
Short descriptionDefines the mode used by the ramp system
ModeRFC‑A
Minimum0Maximum3
Default1Units 
Type8 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW, TE

ValueTextDescription
0FastFast ramp
1StdStandard ramp with normal motor voltage
2Std.bstStandard ramp with high motor voltage
3Fst.bstFast ramp with high motor volts

Acceleration is defined as a positive (forward) or negative (reverse) frequency change away from zero, and deceleration is defined as a change towards zero. Ramp Mode Select (02.004) defines the ramp mode used for deceleration. During acceleration the frequency changes are based on the final acceleration rate only.

0: Fast ramp
During deceleration the frequency changes are based on the final deceleration rate.

1: Standard ramp
The standard ramp controller operates in a similar way to open-loop mode except that once the standard ramp controller becomes active it remains active until the RFC sequencer leaves the deceleration state. It is possible that the frequency may fall faster than the final deceleration rate as the motor reaches standstill.

2: Standard ramp with motor voltage boost
Standard ramp with motor voltage boost is the same as standard ramp mode except that the magnetising current is boosted to increase the motor losses and reduce the deceleration time.

If the Standard Ramp Voltage (02.008) is set to a level that is below the nominal d.c. link voltage level the motor will coast during deceleration because the torque producing current reference is limited to prevent the motor from accelerating. There are circumstances as listed below where the motor may not decelerated or even accelerate.

  1. With a Synchronous machine a limited amount of motoring torque producing current is allowed to make the system operate correctly and in this case it is possible under some circumstances for the motor to accelerate slowly.
  2. With a high inductance supply it is possible for the d.c. link voltage to rise as the motor frequency approaches zero, and so the motor will continue to rotate slowly and not stop.
  3. An overhauling load can cause the motor to accelerate.

If Deceleration Fail Detection Disable (02.009) is at its default value of 0 the Estimated Frequency (03.002) is monitored. If these do not fall over a period of 10s the ramp output is forced to zero and the d.c. link voltage controller is disabled. If Deceleration Fail Detection Disable (02.009) = 1 this feature is disabled.

3: Fast ramp with motor voltage boost
Fast ramp with motor voltage boost is the same as Fast ramp mode except that the magnetising current is boosted to increase the motor losses and reduce the deceleration time.


Parameter02.005  Disable Ramp Output
Short descriptionSet to 1 to disable the ramp system
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW

See Post Ramp Reference (02.001).


Parameter02.006  S Ramp Enable
Short descriptionSet to 1 to enable the use of S ramps
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW

If S Ramp Enable (02.006) = 0 linear ramps are used, but if S Ramp Enable (02.006) = 1 an acceleration limit is applied to give S ramps. The S ramp function is disabled during deceleration when the standard ramp voltage controller is active. When the motor is accelerated again the acceleration ramp used by the S ramp function is reset to zero.


Parameter02.007  Max Rate Of Change Of Acceleration
Short descriptionDefines the maximum rate of change of acceleration used by the ramp system
ModeRFC‑A
Minimum0.0Maximum300.0
Default3.1Unitss²/100Hz
Type32 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW

A rate of change of acceleration ramp (S ramp) can be applied by different methods depending on the value of S Ramp Set-up Mode (02.041). If S Ramp Set-up Mode (02.041) = 0 then the maximum rate of change of acceleration in both directions, accelerating away from or towards zero, is defined by Max Rate Of Change Of Acceleration (02.007).

The general equations are given below for a linear ramp and an S ramp where

Δw is the required change of frequency.
aMax is the maximum allowed acceleration in units of frequency/s
JMax is the maximum rate of change of acceleration (i.e. jerk) in units of frequency/s2

The time for a linear ramp to give a change of frequency of Δw is

TLinear = Δw x aMax

If an S ramp is used wB is the change of frequency as the acceleration changes from zero to aMax, i.e. the S shaped part of the frequency change.

wB = aMax2 / 2JMax

If the required frequency change is less than 2wB, i.e. Δw B, then the acceleration never reaches its limit and the ramp does not contain a linear ramp section and the time for the ramp is given by

TSramp1 = 2 √ (Δw / JMax)

Otherwise

TSramp2 = (Δw / aMax) + (aMax / JMax)

The diagram below shows a change of frequency from 0Hz to 50Hz with the ramp rate set to 5.0s / 100Hz and the Max Rate Of Change Of Acceleration (02.007) set to its default value of 3.1s2 / 100Hz.

The required change of frequency Δw  = 50Hz. The acceleration and jerk limits are converted from the parameter values as follows:

aMax = 100 / ramp rate = 20.0 Hz/s

JMax = 100 / Max Rate Of Change Of Acceleration (02.007) = 32.3 Hz/s2

The linear ramp time TLinear = Δw x aMax = 50.0 / 20.0 = 2.5s

The frequency change for the acceleration to reach its limit wB = aMax2 / 2JMax = 20.02 / (2 x 32.3) = 6.19Hz

The required frequency change Δw = 50.Hz and this is greater that 2wB, i.e. Δw > 2 x 6.19Hz therefore the time for the ramp

TSramp2 = (Δw / aMax) + (aMax / JMax) = (50.0 / 20.0) + (20.0 / 32.3) = 2.5 + 0.62 = 3.12s.

Note that the default value of Max Rate Of Change Of Acceleration (02.007) has been chosen so that when it is combined with the default acceleration rate, the ramp is extended by approximately 25% compared to the linear ramp.

If the required change of frequency had been 5.0Hz, i.e. less than 2 x wB, then the alternative equation should be used:

TSramp1 = 2 √ (Δw / JMax) = 2 √ (5.0 / 32.3) = 0.78s.


Parameter02.008  Standard Ramp Voltage
Short descriptionDefines the standard ramp voltage used by the ramp system
ModeRFC‑A
Minimum−VM_DC_VOLTAGE_SETMaximumVM_DC_VOLTAGE_SET
DefaultSee exceptions belowUnitsV
Type16 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places0
CodingRW, VM, RA

VoltageRegionDefault Value
110VAll375
200VAll375
400V50Hz750
400V60Hz775
575VAll895
690VAll1075

See Ramp Mode Select (02.004).


Parameter02.009  Deceleration Fail Detection Disable
Short descriptionSet to 1 to disable the deceleration fal detection function
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places0
CodingRW

See Ramp Mode Select (02.004).


Parameter02.010  Acceleration Rate Selector
Short descriptionDefines which acceleration rate is used by the ramp system
ModeRFC‑A
Minimum0Maximum9
Default0Units 
Type8 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW

The Acceleration Rate Selector (02.010) is used to either select an acceleration rate directly or to define the method used to select an acceleration rate. If 1 ≤ Acceleration Rate Selector (02.010) ≤ 8 the acceleration rate is selected directly, i.e. 1 selects Acceleration Rate 1 (02.011), 2 selects Acceleration Rate 2 (02.012), etc. If Acceleration Rate Selector (02.010) = 0 the acceleration rate is selected with the acceleration rate select bits as shown in the table below.

Acceleration Rate Select Bit 2 (02.034) Acceleration Rate Select Bit 1 (02.033) Acceleration Rate Select Bit 0 (02.032) Acceleration rate selected
0 0 0 Acceleration Rate 1 (02.011)
0 0 1 Acceleration Rate 2 (02.012)
0 1 0 Acceleration Rate 3 (02.013)
0 1 1 Acceleration Rate 4 (02.014)
1 0 0 Acceleration Rate 5 (02.015)
1 0 1 Acceleration Rate 6 (02.016)
1 1 0 Acceleration Rate 7 (02.017)
1 1 1 Acceleration Rate 8 (02.018)

If Acceleration Rate Selector (02.010) = 9 the acceleration rate is selected based on the value of Preset Selected Indicator (01.050), i.e. 1 selects Acceleration Rate 1 (02.011), 2 selects Acceleration Rate 2 (02.012), etc.


Parameter02.011  Acceleration Rate 1
Short descriptionDefines the acceleration rate present in acceleration rate 1
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Ramp Rate Units (02.039) for the definition of Ramp rate frequency.

Acceleration Rate 1 (02.011) - Acceleration Rate 8 (02.018) can be selected to define the linear ramp rate. The acceleration rate applies when the frequency is changing away from zero.

Selecting a ramp rate that has been set to zero in Asynchronous mode disables the ramp system so that the Post Ramp Reference (02.001) follows the Pre-ramp Reference (01.003) without any delay for acceleration or deceleration. It should be noted that this also disables the standard ramp d.c. link voltage controller and the frequency based current limits.


Parameter02.012  Acceleration Rate 2
Short descriptionDefines the acceleration rate present in acceleration rate 2
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Acceleration Rate 1 (02.011).


Parameter02.013  Acceleration Rate 3
Short descriptionDefines the acceleration rate present in acceleration rate 3
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Acceleration Rate 1 (02.011).


Parameter02.014  Acceleration Rate 4
Short descriptionDefines the acceleration rate present in acceleration rate 4
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Acceleration Rate 1 (02.011).


Parameter02.015  Acceleration Rate 5
Short descriptionDefines the acceleration rate present in acceleration rate 5
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Acceleration Rate 1 (02.011).


Parameter02.016  Acceleration Rate 6
Short descriptionDefines the acceleration rate present in acceleration rate 6
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Acceleration Rate 1 (02.011).


Parameter02.017  Acceleration Rate 7
Short descriptionDefines the acceleration rate present in acceleration rate 7
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Acceleration Rate 1 (02.011).


Parameter02.018  Acceleration Rate 8
Short descriptionDefines the acceleration rate present in acceleration rate 8
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default5.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Acceleration Rate 1 (02.011).


Parameter02.019  Jog Acceleration Rate
Short descriptionDefines the acceleration rate present when the jog function is selected
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default0.2Unitss
Type32 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW, VM

See Ramp Rate Units (02.039) for the definition of Ramp rate frequency.

The Jog Acceleration Rate (02.019) is selected when Jog Select (01.013) is active and when the frequency is changing away from zero in either direction.


Parameter02.020  Deceleration Rate Selector
Short descriptionDefines which deceleration rate is used by the ramp system
ModeRFC‑A
Minimum0Maximum9
Default0Units 
Type8 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW

The Deceleration Rate Selector (02.020) operates in the same way as the Acceleration Rate Selector (02.010). If Deceleration Rate Selector (02.020) = 0 the deceleration rate is selected with the deceleration rate select bits as shown in the table below.

Deceleration Rate Select Bit 2 (02.037) Deceleration Rate Select Bit 1 (02.036) Deceleration Rate Select Bit 0 (02.035) Deceleration rate selected
0 0 0 Deceleration Rate 1 (02.021)
0 0 1 Deceleration Rate 2 (02.022)
0 1 0 Deceleration Rate 3 (02.023)
0 1 1 Deceleration Rate 4 (02.024)
1 0 0 Deceleration Rate 5 (02.025)
1 0 1 Deceleration Rate 6 (02.026)
1 1 0 Deceleration Rate 7 (02.027)
1 1 1 Deceleration Rate 8 (02.028)


Parameter02.021  Deceleration Rate 1
Short descriptionDefines the deceleration rate present in deceleration rate 1
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Ramp Rate Units (02.039) for the definition of Ramp rate frequency

Deceleration Rate 1 (02.021) - Deceleration Rate 8 (02.028) can be selected to define the linear ramp rate. The deceleration rate applies when the frequency is changing towards zero.

Selecting a ramp rate that has been set to zero in Asynchronous mode disables the ramp system so that the Post Ramp Reference (02.001) follows the Pre-ramp Reference (01.003) without any delay for acceleration or deceleration. It should be noted that this also disables the standard ramp d.c. link voltage controller and the frequency based current limits.


Parameter02.022  Deceleration Rate 2
Short descriptionDefines the deceleration rate present in deceleration rate 2
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Deceleration Rate 1 (02.021).


Parameter02.023  Deceleration Rate 3
Short descriptionDefines the deceleration rate present in deceleration rate 3
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Deceleration Rate 1 (02.021).


Parameter02.024  Deceleration Rate 4
Short descriptionDefines the deceleration rate present in deceleration rate 4
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Deceleration Rate 1 (02.021).


Parameter02.025  Deceleration Rate 5
Short descriptionDefines the deceleration rate present in deceleration rate 5
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Deceleration Rate 1 (02.021).


Parameter02.026  Deceleration Rate 6
Short descriptionDefines the deceleration rate present in deceleration rate 6
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Deceleration Rate 1 (02.021).


Parameter02.027  Deceleration Rate 7
Short descriptionDefines the deceleration rate present in deceleration rate 7
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Deceleration Rate 1 (02.021).


Parameter02.028  Deceleration Rate 8
Short descriptionDefines the deceleration rate present in deceleration rate 8
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default10.0Unitss
Type32 Bit User SaveUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRW, VM

See Deceleration Rate 1 (02.021).


Parameter02.029  Jog Deceleration Rate
Short descriptionDefines the deceleration rate present when the jog function is selected
ModeRFC‑A
Minimum−VM_ACCEL_RATEMaximumVM_ACCEL_RATE
Default0.2Unitss
Type32 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW, VM

See Ramp Rate Units (02.039) for the definition of Ramp rate frequency.

The Jog Deceleration Rate (02.029) is selected when Jog Select (01.013) is active and when the frequency is changing towards zero in either direction.


Parameter02.030  Acceleration Rate Selected
Short descriptionIndicates which acceleration rate is selected
ModeRFC‑A
Minimum0Maximum8
Default Units 
Type8 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRO, ND, NC, PT

Acceleration Rate Selected (02.030) shows a value between 1 and 8 that corresponds to Acceleration Rate 1 (02.011) to Acceleration Rate 8 (02.018) indicating which of these acceleration rates is actually being used.

Deceleration Rate Selected (02.031) shows a value between 1 and 8 that corresponds to Deceleration Rate 1 (02.021) to Deceleration Rate 8 (02.028) indicating which of these deceleration rates is actually being used.


Parameter02.031  Deceleration Rate Selected
Short descriptionIndicates which deceleration rate is selected
ModeRFC‑A
Minimum0Maximum8
Default Units 
Type8 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRO, ND, NC, PT

See Acceleration Rate Selected (02.030).


Parameter02.032  Acceleration Rate Select Bit 0
Short descriptionDefines which acceleration rate is used if acceleration rate selector = 0
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW, NC

See Acceleration Rate Selector (02.010).


Parameter02.033  Acceleration Rate Select Bit 1
Short descriptionDefines which acceleration rate is used if acceleration rate selector = 0
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW, NC

See Acceleration Rate Selector (02.010).


Parameter02.034  Acceleration Rate Select Bit 2
Short descriptionDefines which acceleration rate is used if acceleration rate selector = 0
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW, NC

See Acceleration Rate Selector (02.010).


Parameter02.035  Deceleration Rate Select Bit 0
Short descriptionDefines which deceleration rate is used if deceleration rate selector = 0
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW, NC

See Deceleration Rate Selector (02.020).


Parameter02.036  Deceleration Rate Select Bit 1
Short descriptionDefines which deceleration rate is used if deceleration rate selector = 0
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW, NC

See Deceleration Rate Selector (02.020).


Parameter02.037  Deceleration Rate Select Bit 2
Short descriptionDefines which deceleration rate is used if deceleration rate selector = 0
ModeRFC‑A
Minimum0Maximum1
Default0Units 
Type1 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places0
CodingRW, NC

See Deceleration Rate Selector (02.020).


Parameter02.038  Inertia Compensation Torque
Short descriptionDisplays the torque as a percentage of rated torque
ModeRFC‑A
Minimum-1000.0Maximum1000.0
Default Units%
Type16 Bit VolatileUpdate Rate16ms
Display FormatStandardDecimal Places1
CodingRO, ND, NC, PT

The Motor and Load Inertia (03.018)Torque Per Amp (05.032) and the rate of change of the Post Ramp Reference (02.001) are used to produce a torque feed-forwards value that should accelerate and decelerate the load at the required rate. This value can be used as a feed-forwards term that is added to the speed controller output if Inertia Compensation Enable (04.022) = 1. Inertia Compensation Torque (02.038) gives the torque as a percentage of rated torque.


Parameter02.039  Ramp Rate Units
Short descriptionDefines the units used by the ramp system
ModeRFC‑A
Minimum0Maximum2
Default0Units 
Type8 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places0
CodingRW

The ramp rate parameters (Acceleration Rate 1 (02.011) - Acceleration Rate 8 (02.018), Jog Acceleration Rate (02.019), Deceleration Rate 1 (02.021) - Deceleration Rate 8 (02.028) and Jog Deceleration Rate (02.029)) are specified in s / Ramp rate. Ramp rate frequency is selected with Ramp Rate Units (02.039) as defined in the table below.

Ramp Rate Units (02.039) Ramp rate frequency
0 Seconds per 100Hz
1 Seconds per Maximum Frequency
2 Seconds per 1000Hz

Maximum frequency is defined by Maximum Reference Clamp (01.006) if Select Motor 2 Parameters (11.045) = 0, or M2 Maximum Reference Clamp (21.001) if Select Motor 2 Parameters (11.045) = 1.


Parameter02.040  S Ramp Percentage
Short descriptionDefines the profile of the S ramp system as a percentage
ModeRFC‑A
Minimum0.0Maximum50.0
Default0.0Units%
Type16 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW

If S Ramp Set-up Mode (02.041) = 1 the percentage of the ramp to Maximum frequency that includes half the S ramp profile can be specified with S Ramp Percentage (02.040) as shown in the diagram below. Maximum frequency is defined by Maximum Reference Clamp (01.006) if Select Motor 2 Parameters (11.045) = 0, or M2 Maximum Reference Clamp (21.001) if Select Motor 2 Parameters (11.045) = 1. It should be noted that the time to ramp to Maximum frequency does not change as S Ramp Percentage (02.040) is changed, but the maximum acceleration rate in the centre of the profile increases.


Parameter02.041  S Ramp Set-up Mode
Short descriptionDefines the mode used by the S ramp system
ModeRFC‑A
Minimum0Maximum2
Default0Units 
Type8 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places0
CodingRW

S Ramp Set-up Mode (02.041) defines the method used to set up the S ramp function.

0: Single maximum rate of change of acceleration
The maximum rate of change of acceleration in either direction, when the frequency is changing away from or towards zero, is defined by Max Rate Of Change Of Acceleration (02.007).

1: S ramp percentage
A single maximum rate of change of acceleration is used in either direction, when the frequency is changing away from or towards zero, but this is specified as the percentage of the ramp from zero to Maximum frequency which is covered by the S shaped profile. See S Ramp Percentage (02.040).

2: Four independent maximum rate of change of acceleration values
The maximum rate of change of acceleration can be specified as four independent values. See Max Rate Of Change Of Acceleration (02.007).


Parameter02.042  Maximum Rate Of Change Of Acceleration 1
Short descriptionDefines the 1st maximum rate of change of acceleration used by the S ramp system
ModeRFC‑A
Minimum0.0Maximum300.0
Default0.0Unitss²/100Hz
Type32 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW

If S Ramp Set-up Mode (02.041) = 2 it is possible to set up four independent maximum rate of change of acceleration values as shown in the diagram below. The values from 1 to 4 correspond to Maximum Rate Of Change Of Acceleration 1 (02.042) to Maximum Rate Of Change Of Acceleration 4 (02.045) respectively.


Parameter02.043  Maximum Rate Of Change Of Acceleration 2
Short descriptionDefines the 2nd maximum rate of change of acceleration used by the S ramp system
ModeRFC‑A
Minimum0.0Maximum300.0
Default0.0Unitss²/100Hz
Type32 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW

See Maximum Rate Of Change Of Acceleration 1 (02.042).


Parameter02.044  Maximum Rate Of Change Of Acceleration 3
Short descriptionDefines the 3rd maximum rate of change of acceleration used by the S ramp system
ModeRFC‑A
Minimum0.0Maximum300.0
Default0.0Unitss²/100Hz
Type32 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW

See Maximum Rate Of Change Of Acceleration 1 (02.042).


Parameter02.045  Maximum Rate Of Change Of Acceleration 4
Short descriptionDefines the 4th maximum rate of change of acceleration used by the S ramp system
ModeRFC‑A
Minimum0.0Maximum300.0
Default0.0Unitss²/100Hz
Type32 Bit User SaveUpdate RateBackground read
Display FormatStandardDecimal Places1
CodingRW

See Maximum Rate Of Change Of Acceleration 1 (02.042).