Delta VFD-EL-W Series, User Manual

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Chapter 4 Parameters

VFD-EL-W
4-73
 Sets the DC current level input to the motor during preheating. The DC current during preheating is 100%
equal to the Motor Rated Current (Pr.07.00). When setting this parameter, increase the current level slowly
until you reach the desired preheating temperature.
 Related parameters: Pr.08.22 (DC Current Cycle Time during Preheating), Pr.03.00 (Multi-function Output
Relay #24: Preheating function indication), Pr.04.06–Pr.04.08 (Multi-function Input Terminal #26: Auto-trigger
preheating function).
08.22 DC Current Cycle Time during Preheating
Settings 0–100% Default: 0
 Sets the cycle time that the DC current input to the motor during preheating. 0–100% corresponds to 0–10
seconds. When you set the cycle time to 0%, it means that there is no current output; 100% means
continuous current output. For example, if you set the cycle time to 50%, the time that the current input to the
motor for one cycle is five seconds; the stopping time is five seconds. When the AC motor drive stops
running, continuous DC current automatically and cyclically input to the motor. When you use this parameter
with MI=26 (Auto-trigger preheating function), this parameter works with the MI signal continuously and
cyclically until the AC motor drive starts the motor operation or MI=26 is disabled.
 The preheating function works when Pr.08.21 and Pr.08.22 are not set to 0.
 When MI=26 (Auto-trigger preheating function) is enabled, MI terminal determines the preheating function.

When MI=26 is disabled, the preheating function is enabled after the AC motor drive stops its first operation or
when the AC motor drive starts after re-applying power.

The diagram below shows the 50% setting for the cycle time that the DC current input to the motor during
preheating when MI=26 (Auto-trigger preheating function) is enabled.
 The diagram below shows the 50% setting for the cycle time that the DC current input to the motor during
preheating when MI=26 (Auto-trigger preheating function) is disabled. The preheating function automatically
enables continuous current input after the drive stops running.