94
ADV200
WA • Functions description and parameters list
22.7 – FUNCTIONS/POWER LOSS
This function controls a loss of power or temporary mains failure.
When the function is enabled the system stops with the controlled ramp; the power regenerated by the load
sustains the DC link power supply so that the motor speed can be controlled. The speed of the motor is con-
trolled for as long as power can be recovered (motor speed almost zero but not zero), after which the
Under-
voltage
alarm is generated and the motor performs an uncontrolled stop due to inertia.
The function is only effective with loads that accumulate sufficient energy (typically loads with a high moment
of inertia and which the moment the power loss occurs have a speed of rotation not close to zero). The func-
tion cannot be used for passive loads.
The function can only be used with
Regulation mode = V/f control
.
The Powerloss function is enabled when the DC link voltage falls below a threshold configured internally as
a function of the mains voltage at a value that is higher than the
Undervoltage
threshold. When the function
is enabled the drive controls a stop with a user-definable deceleration ramp. In this phase the current limit is
controlled by a regulator on the DC link voltage and the setpoint is a threshold configured internally as a func-
tion of the mains voltage at a value below the
Overvoltage
threshold.
The regulator envisages two setting parameters (proportional and integral) calculated in advance by the drive
as a function of the size of the motor and plate data. If the regulator acts on the current limit the motor speed
does not follow the set deceleration ramp. The function continues for as long as power can be recovered,
after which the
Undervoltage
alarm is generated. If the mains supply is restored during the deceleration ramp
phase, the user can configure how the drive should behave. The following options are available: continue in
any case until reaching zero speed or stop the deceleration ramp and pass to the set reference.
The drive does not automatically recognise the fact that the mains supply has been restored. This information
must be supplied from the outside via the
Powerloss mains src
digital input.
The presence of the braking unit prevents the intervention of the
Overvoltage
alarm and the function has the
advantage of being able to stop the motor while guaranteeing the set time.
As the setpoint of the Powerloss function regulator is higher than the brake activation threshold, it is not ena-
bled and the current limit is not altered to allow compliance with the set deceleration ramp time. The interven-
tion of the braking unit dissipates the energy of the motor in the resistor, reducing the amount of power avail-
able to sustain the DC link and the time available to control stopping of the motor. The presence of the braking
unit could mean that the speed of the motor from which no power can be recovered is higher than that with no
braking unit.
The function can be used on machines with a single drive as well as on machines with several drives, the
speeds of which must always be synchronised.
For machines with a single drive, enabling the Powerloss function is sufficient.
For machines with several drives, the DC links must be connected: the Powerloss function must only be
enabled on the drive identified as the master and not on the slaves. The master drive is normally the one that
controls the load with the highest inertia. The master drive sends the
Powerloss nextratio
signal with the
Содержание ADV200 WA
Страница 84: ...84 ADV200 WA Functions description and parameters list 22 3 FUNCTIONS DC BRAKING ...
Страница 274: ...274 ADV200 WA Block Diagrams G Block Diagrams System Diagrams Index Drive overview ...
Страница 275: ...ADV200 WA Block Diagrams 275 References ...
Страница 276: ...276 ADV200 WA Block Diagrams Ramps Multireference ...
Страница 277: ...ADV200 WA Block Diagrams 277 Motorpotentiometer Jog function ...
Страница 278: ...278 ADV200 WA Block Diagrams Monitor function ...
Страница 279: ...ADV200 WA Block Diagrams 279 ...
Страница 280: ...280 ADV200 WA Block Diagrams Commands ...
Страница 281: ...ADV200 WA Block Diagrams 281 ...
Страница 282: ...282 ADV200 WA Block Diagrams Digital inputs ...
Страница 283: ...ADV200 WA Block Diagrams 283 Digital outputs ...
Страница 284: ...284 ADV200 WA Block Diagrams Analog inputs ...
Страница 285: ...ADV200 WA Block Diagrams 285 ...
Страница 286: ...286 ADV200 WA Block Diagrams Analog outputs ...
Страница 287: ...ADV200 WA Block Diagrams 287 Speed reg gains ...
Страница 288: ...288 ADV200 WA Block Diagrams VF parameters ...
Страница 289: ...ADV200 WA Block Diagrams 289 Functions ...
Страница 290: ...290 ADV200 WA Block Diagrams ...
Страница 291: ...ADV200 WA Block Diagrams 291 ...
Страница 292: ...292 ADV200 WA Block Diagrams ...
Страница 293: ...ADV200 WA Block Diagrams 293 Process ...
Страница 294: ...294 ADV200 WA Block Diagrams ...
Страница 295: ...ADV200 WA Block Diagrams 295 ...
Страница 296: ...296 ADV200 WA Block Diagrams ...
Страница 297: ...ADV200 WA Block Diagrams 297 ...
Страница 298: ...298 ADV200 WA Block Diagrams ...
Страница 299: ......