# Variable Minimums/Maximums

The descriptions below define the variable minimum/maximum pairs that can be used with parameters when the VM format bit is set. The variable minimum and maximum themselves can be dependent on other parameters, or the drive rating or other conditions as defined. The variable minimum and the variable maximum have a limited range and this is defined for each minimum/maximum pair.

Identifier | VM_AC_VOLTAGE
--- | ---
Description | Range applied to parameters showing a.c. voltage
Units | V
Range of [MIN] | 0
Range of [MAX] | 0 to 930

VM_AC_VOLTAGE[MAX] in drive voltage rating dependent. See the table below.

Voltage level | 200V | 400V | 575V | 690V
VM_AC_VOLTAGE[MAX] | 325 | 650 | 780 | 930

VM_AC_VOLTAGE[MIN] = 0

Identifier | VM_AC_VOLTAGE_SET
--- | ---
Description | Range applied to a.c. voltage set-up parameters
Units | V
Range of [MIN] | 0
Range of [MAX] | 0 to 765

VM_AC_VOLTAGE_SET[MAX] is drive voltage rating dependent. See the table below.

Voltage level | 200V | 400V | 575V | 690V
VM_AC_VOLTAGE_SET[MAX] frame size 1 to 4 | 240 | 480 | N/A | N/A
VM_AC_VOLTAGE_SET[MAX] frame size 5 to 9 | 265 | 530 | 635 | 765

VM_AC_VOLTAGE_SET[MIN] = 0

Identifier | VM_ACCEL_RATE
--- | ---
Description | Maximum applied to the ramp rate parameters
Units | s/100Hz, s/1000Hz, s/MaxFrequency
Range of [MIN] | 0.0
Range of [MAX] | 0.0 to 3200.0

A maximum needs to be applied to the ramp rate parameters because the units are a time for a change of speed from zero to a defined level or to maximum speed. If the change of speed is to the maximum speed then changing the maximum speed changes the actual ramp rate for a given ramp rate parameter value. The variable maximum calculation ensures that longest ramp rate (parameter at its maximum value) is not slower than the rate with the defined level, i.e. 3200.0 s/100Hz.
The maximum frequency is taken from 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.

VM_ACCEL_RATE[MIN] = 0.0

If Ramp Rate Units (02.039) = 0:
VM_ACCEL_RATE[MAX] = 3200.0
Otherwise:
VM_ACCEL_RATE[MAX] = 3200.0 x Maximum frequency / 100.00

Identifier | VM_DC_VOLTAGE
--- | ---
Description | Range applied to d.c. voltage reference parameters
Units | V
Range of [MIN] | 0
Range of [MAX] | 0 to 1190

VM_DC_VOLTAGE[MAX] is the full scale d.c. link voltage feedback (over voltage trip level) for the drive. This level is drive voltage rating dependent. See the table below.

Voltage level | 200V | 400V | 575V | 690V
VM_DC_VOLTAGE[MAX] frame size 1 to 4 | 510 | 870 | N/A | N/A
VM_DC_VOLTAGE[MAX] frame size 5 to 9 | 415 | 830 | 990 | 1190

VM_DC_VOLTAGE[MIN] = 0

Identifier | VM_DC_VOLTAGE_SET
--- | ---
Description | Range applied to d.c. voltage reference parameters
Units | V
Range of [MIN] | 0
Range of [MAX] | 0 to 1150

VM_DC_VOLTAGE_SET[MAX] is drive voltage rating dependent. All values are shown in the table below.

Voltage level | 200V | 400V | 575V | 690V
VM_DC_VOLTAGE_SET[MAX] | 400 | 800 | 955 | 1150

VM_DC_VOLTAGE_SET[MIN] = 0

Identifier | VM_DRIVE_CURRENT
--- | ---
Description | Range applied to parameters showing current in A
Units | A
Range of [MIN] | -9999.99 to 0.00
Range of [MAX] | 0.00 to 9999.99

VM_DRIVE_CURRENT[MAX] is equivalent to the full scale (over current trip level) for the drive and is given by Full Scale Current Kc (11.061).

VM_DRIVE_CURRENT[MIN] = - VM_DRIVE_CURRENT[MAX]

Identifier | VM_FREQ
--- | ---
Description | Range applied to parameters showing frequency
Units | Hz
Range of [MIN] | -1100.00
Range of [MAX] | 1100.00

This variable minimum/maximum defines the range of speed monitoring parameters. To allow headroom for overshoot the range is set to twice the range of the speed references.

VM_FREQ[MIN] = 2 x VM_SPEED_FREQ_REF[MIN]

VM_FREQ[MAX] = 2 x VM_SPEED_FREQ_REF[MAX]

Identifier | VM_MAX_SWITCHING_FREQUENCY
--- | ---
Description | Range applied to the maximum switching frequency parameters
Units | User units
Range of [MIN] | OpenLoop: 0 (0.667kHz), RFC-A: 2 (2kHz)
Range of [MAX] | 8 (16kHz)

VM_SWITCHING_FREQUENCY[MAX] = Power stage dependent

VM_SWITCHING_FREQUENCY[MIN] = 0

Identifier | VM_MOTOR1_CURRENT_LIMIT
--- | ---
Description | Range applied to current limit parameters (motor 1)
Units | %
Range of [MIN] | 0.0
Range of [MAX] | 0.0 to 1000.0

VM_MOTOR1_CURRENT_LIMIT[MAX] is dependent on the drive rating and motor set-up parameters.

VM_MOTOR1_CURRENT_LIMIT[MIN] = 0.0

Identifier | VM_MOTOR2_CURRENT_LIMIT
--- | ---
Description | Range applied to current limit parameters (motor 2)
Units | %
Range of [MIN] | 0.0
Range of [MAX] | 0.0 to 1000.0

VM_MOTOR2_CURRENT_LIMIT[MAX] is dependent on the drive rating and motor set-up parameters.

VM_MOTOR2_CURRENT_LIMIT[MIN] = 0.0

Identifier | VM_NEGATIVE_REF_CLAMP1
--- | ---
Description | Limits applied to the negative frequency clamp (motor 1)
Units | Hz
Range of [MIN] | -550.00 to 0.00
Range of [MAX] | 0.00 to 550.00

This variable maximum/minimum defines the range of the negative frequency clamp associated with motor map 1 (Minimum Reference Clamp (01.007)). The minimum and maximum are affected by the settings of the Negative Reference Clamp Enable (01.008), Bipolar Reference Enable (01.010) and Maximum Reference Clamp (01.006) as shown in the table below.

Negative Reference Clamp Enable (01.008) | Bipolar Reference Enable (01.010) | VM_NEGATIVE_REF_CLAMP1[MIN] | VM_NEGATIVE_REF_CLAMP1[MAX]
0 | 0 | 0.00 | Pr 01.006
0 | 1 | 0.00 | 0.00
1 | X | -VM_POSITIVE_REF_CLAMP[MAX] | 0.00

Identifier | VM_NEGATIVE_REF_CLAMP2
--- | ---
Description | Limits applied to the negative frequency clamp (motor 2)
Units | Hz
Range of [MIN] | -550.00 to 0.00
Range of [MAX] | 0.00 to 550.00

This variable maximum/minimum defines the range of the negative frequency clamp associated with motor map 2 (M2 Minimum Reference Clamp (21.002)). It is defined in the same way as VM_NEGATIVE_REF_CLAMP1 except that the M2 Maximum Reference Clamp (21.001) is used instead of Maximum Reference Clamp (01.006).

Identifier | VM_POSITIVE_REF_CLAMP
--- | ---
Description | Limits applied to the positive frequency reference clamp
Units | Hz
Range of [MIN] | 0.00
Range of [MAX] | 550.00

VM_POSITIVE_REF_CLAMP[MAX] defines the range of the positive reference clamp, Maximum Reference Clamp (01.006), which in turn limit the references.

Identifier | VM_POWER
--- | ---
Description | Range applied to parameters that either set or display power
Units | kW
Range of [MIN] | -9999.99 to 0.00
Range of [MAX] | 0.00 to 9999.99

VM_POWER[MAX] is rating dependent and is chosen to allow for the maximum power that can be output by the drive with maximum a.c. output voltage, at maximum controlled current and unity power factor.

VM_POWER[MAX] = √3 x VM_AC_VOLTAGE[MAX] x VM_DRIVE_CURRENT[MAX] / 1000

VM_POWER[MIN] = -VM_POWER[MAX]

Identifier | VM_RATED_CURRENT
--- | ---
Description | Range applied to rated current parameters
Units | A
Range of [MIN] | 0.00
Range of [MAX] | 0.00 to 9999.99

VM_RATED_CURRENT [MAX] = Maximum Rated Current (11.060) and is dependent on the drive rating.

VM_RATED_CURRENT [MIN] = 0.00

Identifier | VM_SPEED_FREQ_REF
--- | ---
Description | Range applied to the frequency reference parameters
Units | Hz
Range of [MIN] | -550.00 to 0.00
Range of [MAX] | 0.00 to 550.00

This variable minimum/maximum is applied throughout the frequency and speed reference system so that the references can vary in the range from the minimum to maximum clamps.

Negative Reference Clamp Enable (01.008) | VM_SPEED_FREQ_REF[MAX] if Select Motor 2 Parameters (11.045) = 0 | VM_SPEED_FREQ_REF[MAX] if Select Motor 2 Parameters (11.045) = 1
0 | Maximum Reference Clamp (01.006) | M2 Maximum Reference Clamp (21.001)
1 | Maximum Reference Clamp (01.006) or |Minimum Reference Clamp (01.007)| whichever the larger | M2 Maximum Reference Clamp (21.001) or |M2 Minimum Reference Clamp (21.002)| whichever the larger

VM_SPEED_FREQ_REF[MIN] = -VM_SPEED_FREQ_REF[MAX].

Identifier | VM_SPEED_FREQ_REF_UNIPOLAR
--- | ---
Description | Unipolar version of VM_SPEED_FREQ_REF
Units | Hz
Range of [MIN] | 0.00
Range of [MAX] | 0.00 to 550.00

VM_SPEED_FREQ_REF_UNIPOLAR[MAX] = VM_SPEED_FREQ_REF[MAX]

VM_SPEED_FREQ_REF_UNIPOLAR[MIN] = 0.00

Identifier | VM_SPEED_FREQ_USER_REFS
--- | ---
Description | Range applied to analogue reference parameters
Units | Hz
Range of [MIN] | -550.00 to 550.00
Range of [MAX] | 0.00 to 550.00

This variable maximum is applied to Analogue Reference 1 (01.036), Analogue Reference 2 (01.037) and Keypad Reference (01.017).

The maximum applied to these parameters is the same as other frequency reference parameters.

VM_SPEED_FREQ_USER_REFS [MAX] = VM_SPEED_FREQ_REF[MAX]

However the minimum is dependent on Negative Reference Clamp Enable (01.008) and Bipolar Reference Enable (01.010).

Negative Reference Clamp Enable (01.008) | Bipolar Reference Enable (01.010) | VM_SPEED_FREQ_USER_REFS[MIN]
0 | 0 | If Select Motor 2 Parameters (11.045) = 0 Minimum Reference Clamp (01.007), otherwise M2 Minimum Reference Clamp (21.002)
0 | 1 | -VM_SPEED_FREQ_REF[MAX]
1 | 0 | 0.00
1 | 1 | -VM_SPEED_FREQ_REF[MAX]

Identifier | VM_SUPPLY_LOSS_LEVEL
--- | ---
Description | Range applied to the supply loss threshold
Units | V
Range of [MIN] | 0 to 1150
Range of [MAX] | 0 to 1150

VM_SUPPLY_LOSS_LEVEL[MAX] = VM_DC_VOLTAGE_SET[MAX]

VM_SUPPLY_LOSS_LEVEL[MIN] is drive voltage rating dependent. See the table below.

Voltage level | 200V | 400V | 575V | 690V
VM_SUPPLY_LOSS_LEVEL[MIN] | 205 | 410 | 540 | 540

Identifier | VM_TORQUE_CURRENT
--- | ---
Description | Range applied to torque and torque producing current parameters.
Units | %
Range of [MIN] | -1000.0 to 0.0
Range of [MAX] | 0.0 to 1000.0

Select Motor 2 Parameters (11.045) | VM_TORQUE_CURRENT[MAX]
0 | VM_MOTOR1_CURRENT_LIMIT[MAX]
1 | VM_MOTOR2_CURRENT_LIMIT[MAX]

VM_TORQUE_CURRENT[MIN] = -VM_TORQUE_CURRENT[MAX]

Identifier | VM_TORQUE_CURRENT_UNIPOLAR
--- | ---
Description | Unipolar version of VM_TORQUE_CURRENT
Units | %
Range of [MIN] | 0.0
Range of [MAX] | 0.0 to 1000.0

VM_TORQUE_CURRENT_UNIPOLAR[MAX] = VM_TORQUE_CURRENT[MAX]

VM_TORQUE_CURRENT_UNIPOLAR[MIN] =0.0

Identifier | VM_USER_CURRENT
--- | ---
Description | Range applied to torque reference and percentage load parameters with one decimal place
Units | %
Range of [MIN] | -1000.0 to 0.0
Range of [MAX] | 0.0 to 1000.0

VM_USER_CURRENT[MAX] = User Current Maximum Scaling (04.024)

VM_USER_CURRENT[MIN] = -VM_USER_CURRENT[MAX]