# Menu 2 − Frequency Ramps

Parameter | 02.001 Post Ramp Reference
--- | ---
Short description | Displays the output of the ramp system
Minimum | −VM_SPEED_FREQ_REF | Maximum | VM_SPEED_FREQ_REF
Default |  | Units | Hz
Type | 32 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 2
Coding | RO, VM, ND, NC, PT

The Post Ramp Reference (02.001) is combined with the slip compensation frequency to define the output frequency of the drive. The Post Ramp Reference (02.001) is defined by the output of the ramp system except when the current limits are active (see Menu 04).

Parameter | 02.003 Ramp Hold
--- | ---
Short description | Set to 1 to hold the ramp system at its present value
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | 1ms
Display Format | Standard | Decimal Places | 0
Coding | RW

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.

Parameter | 02.004 Ramp Mode Select
--- | ---
Short description | Defines the mode used by the ramp system
Minimum | 0 | Maximum | 3
Default | 1 | Units |
Type | 8 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text | Description
0 | Fast | Fast ramp
1 | Std | Standard ramp with normal motor voltage
2 | Std.bst | Standard ramp with high motor voltage
3 | Fst.bst | Fast 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 (shown in the diagram below) is only enabled when the Pre-ramp Reference (01.003) is closer to zero than the Post Ramp Reference (02.001), i.e. during deceleration. As the motor slows down power is fed into the d.c. link of the drive which causes the voltage to rise. When the voltage reaches the level defined by the Standard Ramp Voltage (02.008) the d.c. link voltage controller becomes active and provides a torque producing current reference. This system regulates the d.c. link voltage to hold it at the level defined by the Standard Ramp Voltage (02.008). Generally as the motor slows down the deceleration needs to be increased to provide enough power to maintain the d.c. link level. The frequency is not allowed to fall faster than the final deceleration rate, and so a point is reached where the controller de-activates itself, and the final deceleration rate is used until the motor reaches standstill. If at any point the Pre-ramp Reference (01.003) is equal to or further from zero than the Post Ramp Reference (02.001), i.e. not decelerating, the d.c. link voltage controller is de-activated.

2: Standard ramp with motor voltage boost
Standard ramp with motor voltage boost is the same as standard ramp mode except that the motor voltage is boosted by 20% 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 Output Frequency (05.001) 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 motor voltage is boosted by 20% to increase the motor losses and reduce the deceleration time.

Parameter | 02.006 S Ramp Enable
--- | ---
Short description | Set to 1 to enable the use of S ramps
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW

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.

Parameter | 02.007 Max Rate Of Change Of Acceleration
--- | ---
Short description | Defines the maximum rate of change of acceleration used by the ramp system
Minimum | 0.0 | Maximum | 300.0
Default | 3.1 | Units | s²/100Hz
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW

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.

Parameter | 02.008 Standard Ramp Voltage
--- | ---
Short description | Defines the standard ramp voltage used by the ramp system
Minimum | −VM_DC_VOLTAGE_SET | Maximum | VM_DC_VOLTAGE_SET
Default | See exceptions below | Units | V
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, VM, RA

Voltage | Region | Default Value
110V | All | 375
200V | All | 375
400V | 50Hz | 750
400V | 60Hz | 775
575V | All | 895
690V | All | 1075

See Ramp Mode Select (02.004).

Parameter | 02.009 Deceleration Fail Detection Disable
--- | ---
Short description | Set to 1 to disable the deceleration fal detection function
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Ramp Mode Select (02.004).

Parameter | 02.010 Acceleration Rate Selector
--- | ---
Short description | Defines which acceleration rate is used by the ramp system
Minimum | 0 | Maximum | 9
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW

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.

Parameter | 02.011 Acceleration Rate 1
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 1
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, 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.

Parameter | 02.012 Acceleration Rate 2
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 2
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Acceleration Rate 1 (02.011).

Parameter | 02.013 Acceleration Rate 3
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 3
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Acceleration Rate 1 (02.011).

Parameter | 02.014 Acceleration Rate 4
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 4
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Acceleration Rate 1 (02.011).

Parameter | 02.015 Acceleration Rate 5
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 5
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Acceleration Rate 1 (02.011).

Parameter | 02.016 Acceleration Rate 6
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 6
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Acceleration Rate 1 (02.011).

Parameter | 02.017 Acceleration Rate 7
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 7
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Acceleration Rate 1 (02.011).

Parameter | 02.018 Acceleration Rate 8
--- | ---
Short description | Defines the acceleration rate present in acceleration rate 8
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 5.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Acceleration Rate 1 (02.011).

Parameter | 02.019 Jog Acceleration Rate
--- | ---
Short description | Defines the acceleration rate present when the jog function is selected
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 0.2 | Units | s
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW, 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.

Parameter | 02.020 Deceleration Rate Selector
--- | ---
Short description | Defines which deceleration rate is used by the ramp system
Minimum | 0 | Maximum | 9
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW

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)

Parameter | 02.021 Deceleration Rate 1
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 1
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, 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.

Parameter | 02.022 Deceleration Rate 2
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 2
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Deceleration Rate 1 (02.021).

Parameter | 02.023 Deceleration Rate 3
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 3
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Deceleration Rate 1 (02.021).

Parameter | 02.024 Deceleration Rate 4
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 4
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Deceleration Rate 1 (02.021).

Parameter | 02.025 Deceleration Rate 5
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 5
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Deceleration Rate 1 (02.021).

Parameter | 02.026 Deceleration Rate 6
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 6
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Deceleration Rate 1 (02.021).

Parameter | 02.027 Deceleration Rate 7
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 7
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Deceleration Rate 1 (02.021).

Parameter | 02.028 Deceleration Rate 8
--- | ---
Short description | Defines the deceleration rate present in deceleration rate 8
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 10.0 | Units | s
Type | 32 Bit User Save | Update Rate | 16ms
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

See Deceleration Rate 1 (02.021).

Parameter | 02.029 Jog Deceleration Rate
--- | ---
Short description | Defines the deceleration rate present when the jog function is selected
Minimum | −VM_ACCEL_RATE | Maximum | VM_ACCEL_RATE
Default | 0.2 | Units | s
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW, 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.

Parameter | 02.030 Acceleration Rate Selected
--- | ---
Short description | Indicates which acceleration rate is selected
Minimum | 0 | Maximum | 8
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RO, 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.

Parameter | 02.031 Deceleration Rate Selected
--- | ---
Short description | Indicates which deceleration rate is selected
Minimum | 0 | Maximum | 8
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See Acceleration Rate Selected (02.030).

Parameter | 02.032 Acceleration Rate Select Bit 0
--- | ---
Short description | Defines which acceleration rate is used if acceleration rate selector = 0
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

See Acceleration Rate Selector (02.010).

Parameter | 02.033 Acceleration Rate Select Bit 1
--- | ---
Short description | Defines which acceleration rate is used if acceleration rate selector = 0
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

See Acceleration Rate Selector (02.010).

Parameter | 02.034 Acceleration Rate Select Bit 2
--- | ---
Short description | Defines which acceleration rate is used if acceleration rate selector = 0
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

See Acceleration Rate Selector (02.010).

Parameter | 02.035 Deceleration Rate Select Bit 0
--- | ---
Short description | Defines which deceleration rate is used if deceleration rate selector = 0
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

See Deceleration Rate Selector (02.020).

Parameter | 02.036 Deceleration Rate Select Bit 1
--- | ---
Short description | Defines which deceleration rate is used if deceleration rate selector = 0
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

See Deceleration Rate Selector (02.020).

Parameter | 02.037 Deceleration Rate Select Bit 2
--- | ---
Short description | Defines which deceleration rate is used if deceleration rate selector = 0
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 16ms
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

See Deceleration Rate Selector (02.020).

Parameter | 02.039 Ramp Rate Units
--- | ---
Short description | Defines the units used by the ramp system
Minimum | 0 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

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.

Parameter | 02.040 S Ramp Percentage
--- | ---
Short description | Defines the profile of the S ramp system as a percentage
Minimum | 0.0 | Maximum | 50.0
Default | 0.0 | Units | %
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW

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.

Parameter | 02.041 S Ramp Set-up Mode
--- | ---
Short description | Defines the mode used by the S ramp system
Minimum | 0 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

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).

Parameter | 02.042 Maximum Rate Of Change Of Acceleration 1
--- | ---
Short description | Defines the 1st maximum rate of change of acceleration used by the S ramp system
Minimum | 0.0 | Maximum | 300.0
Default | 0.0 | Units | s²/100Hz
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW

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.

Parameter | 02.043 Maximum Rate Of Change Of Acceleration 2
--- | ---
Short description | Defines the 2nd maximum rate of change of acceleration used by the S ramp system
Minimum | 0.0 | Maximum | 300.0
Default | 0.0 | Units | s²/100Hz
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW

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

Parameter | 02.044 Maximum Rate Of Change Of Acceleration 3
--- | ---
Short description | Defines the 3rd maximum rate of change of acceleration used by the S ramp system
Minimum | 0.0 | Maximum | 300.0
Default | 0.0 | Units | s²/100Hz
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW

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

Parameter | 02.045 Maximum Rate Of Change Of Acceleration 4
--- | ---
Short description | Defines the 4th maximum rate of change of acceleration used by the S ramp system
Minimum | 0.0 | Maximum | 300.0
Default | 0.0 | Units | s²/100Hz
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW

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