Reliance electric GV3000SE, Инструкция по эксплуатации

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6 - VECTOR REGULATION MODE
49'1329 e GV3000/SE 6 - 9
U.005 Motor Nameplate RPM
Adjustment Range: The actual adjustment range varies with settings of U.002 and U.003:
Number of Poles (U.002) Range of RPM at 50Hz (U.003) Range of RPM at 60Hz (U.003)
2 2700 - 2997 3240 - 3596
4 1350 - 1498 1620 - 1798
6 0900 - 0999 1080 - 1198
8 0675 - 0749 0810 - 0899
Default Setting: 1450 (=1450 RPM) (with P.049 set for 'European Default Setting')
Type: Configurable (at standby only)
Refer to: U.002 Motor Poles
U.003 Motor Nameplate Base Frequency
U.008 Torque Self-Tune Enable
Description: This parameter identifies the motor rated RPM as it appears on the motor
nameplate. It should define the speed of the motor, when
−
driven at nominal frequency (U.003) and fixed number of motor poles (U.002) with
−
nominal motor voltage (U.007) and
−
loaded to nominal level, so that the motor takes nominal current (U.004).
IMPORTANT: Most motor manufacturers tend to print the nameplate with a worst case
nominal speed, which is lower than true speed at nominal load. Frequency inverters with
V/Hz controller don’t care about wrong nameplate values for nominal speed, but vector
controllers are sensitive to that. Therefore check the setting of parameter U.005 as
described in point 6 of ‘Basic Controller Checks’, page 6-25.
IMPORTANT: U.005 must be set prior to activating the torque control self-tuning operation
(U.008).
ATTENTION: The setting of parameters U.001 (Encoder PPR), U.002 (Motor
Poles), U.003 (Motor Nameplate Base Frequency), U.005 (Motor Nameplate
RPM), and U.017 (Motor Top Speed) determines the motor maximum speed.
Motor Nameplate RPM (U.005) has an increasing influence on motor voltage with
rising load, Refer to Figure 6-3 on page 27. Since slip is forced to the motor
(different to slip compensation of a V/Hz inverter), wrong slip forces different
magnetizing current into the motor, causing a change of V/Hz ratio. U.005 will not
be tuned by ‘torque self tuning’ procedure, but relies only on true nameplate values
- which might be wrong.
−
If the value is too close to the synchronous RPM, the drive may exhibit instability.
This value directly affects torque linearity and the maximum attainable
horsepower.
−
If the value is too low relative to the true Nominal Motor RPM, the loaded drive
may not produce expected torque. (U.007 Motor Nominal Voltage will not be
reached at U.016 Field Weakening Start RPM).