Vacon 50X, Руководство пользователя

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69 vacon vacon 50x parameters
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This parameter provides an alternate ramping time for the drive when decelerating, con-
figuring the length of time to decelerate from the value of parameter 302 (Max Frequen-
cy) to 0 Hz. This deceleration ramp is selected by parameter 401 (Ramp Select) or
Sequencer Configuration.
Note that extremely short deceleration times may result in nuisance fault trips or may
require an external dynamic brake or regen current limit.
DC injection braking may be used to stop the motor more quickly than is possible by ei-
ther a ramp-to-stop or a coast to-stop. The Vacon 50X drive allows DC braking to be ini-
tiated either when a digital input assigned to DC braking becomes true, when a specified
frequency is reached, or when either of these events occurs.
When using a digital input for DC braking, you must use one of the DI parameters to con-
figure the selected digital input for DC braking. The amount of braking force is set by pa-
rameter 408 (DC Inject Level). The length of time that the braking force is applied is
determined by the time that the selected digital input is active. The second type of DC in-
jection braking supported by the Vacon 50X drive is where DC braking occurs at a speci-
fied frequency. The duration of the braking is adjusted by parameter 407 (DC Inject Time).
With this type of braking, as the drive slows down after a Stop command, DC braking be-
gins when the frequency reaches the value set in parameter 409 (DC Inj Freq). If the fre-
quency at the time of a Stop command is less than that of DC Inj Freq, DC braking begins
immediately. The braking continues for the time period specified by parameter DC Inj
Time. Once the time period elapses, the drive may be restarted.
Parameter Value Description
DC at Stop DC inject only on Stop
DC at Start DC inject only on Start
DC at Both DC inject only on both Start and Stop
DC on Freq DC inject only on Stop below the set frequency
If parameter 406 is set to DC at Stop (see page 69), direct current is applied to the motor.
This parameter, DC Inject Time, determines how long the direct current will be applied,
and how long DC is applied at Start if programmed accordingly.
This parameter works in tandem with parameter 410 (DC Inject Config) and the other pa-
rameters associated with DC Inject Config. That is, the time period configured by this pa-
rameter, DC Inject Time, determines how long DC injection braking will be active. When
DC injection braking is controlled by a digital input, the braking continues for as long as
the digital input is true, plus the time set by parameter 407 (DC Inject Time). When it is
controlled by frequency, however, it continues for the length of time once the drive reach-
es the frequency set by parameter 409 (DC Inj Freq).
Configures the amount of DC injection that will occur when direct current is injected into
the motor windings, which acts as a braking force. The amount of current is expressed
as a percentage of nominal motor current. The braking force may be applied when start-
ing or stopping. If this parameter is set to 0.0%, the DC injection is disabled.
405 Decel Time 2 Default: 3.0 s
Range: 0.1–3200.0 s
Level 2
406 DC Inject Config Default: DC at Stop
Range: Text string
Level 2
407 DC Inject Time Default: 0.2 sec
Range: 0.0 to 5.0 sec
Level 2
408 DC Inject Level Default: 50.0%
Range: 0.0% to 100.0%
Level 2