Toshiba VF-A7 instruction manual DC injection braking

[Parameter setting]

Title	Function	Adjustment range	Default setting
	0Hz dead band frequency	～ [Hz]	

Frequency after 0Hz dead band operation carried out.



0 [Hz]

notes 1) This function is invalid to preset-speed operation. notes 2) It is effective as frequency instructions to the

frequency reference chosen by the priority processing by , , communication, etc.

notes 3) The addition and multiplication of the override

	function is carried out to the frequency in which
Frequency reference
	this function operated.

6.8 DC injection braking

6.8.1 DC injection braking

 ：DC injection braking start frequency

 ：DC injection braking current

 ：DC injection braking time

 ：Forward/reverse DC braking priority control

・Function

These parameters apply a direct current to the motor to obtain large braking torque. These parameters are used to set the direct current to be applied to the motor, the braking time and the braking start frequency.

[Parameter setting]

Title Function

	DC injection braking start frequency
	DC injection braking current
	DC injection braking time
	Forward/reverse DC braking priority control

Adjustment range

～ [Hz] ～ [%] ～ [s]

: OFF, : ON

Default setting









Output frequency [Hz]	DC injection braking
Reference		Display of  blinks
DC injection braking
start frequency 
０		[s]
Output current [A]

DC injection braking current



０

DC injection braking time



	（	）	ON
Operating signal			OFF
		F-CC

Note) The sensitivity of the inverter's overload protective function increases during D.C. braking. To avoid tripping, the inverter may automatically adjust the D.C. braking rate. When DC injection braking current  is set at 60% or more at the time of standard motor use, by setup of DC injection braking time , overload protection may operate by motor overload protection level. Do not set 0.0% to DC injection braking current .

<D.C. braking start conditions>

The forward/reverse DC braking priority control function  recognizes certain conditions as stop commands from the inverter, and is activated when the output frequency goes down below the DC injection braking start frequency set with . In this case, the conditions under which DC injection braking starts include not only the issue of a start or stop command from the control panel or an external input device, but also a fall in the reference frequency below the value set with  (stop frequency setting) or a fall in the output frequency below the operation stop frequency.

F-15