Hitachi SJ700-2 instruction manual Ii Example 5-a when the stop command is input

Chapter 4 Explanation of Functions

(3) Internal DC braking (A051: 01)

You can apply DC braking to the motor even without entering braking signals via the DB terminal when the inverter starts and stops. To use the internal DC braking function, specify "01" for the DC braking enable (A051).

Use function "A057" to set the DC braking force for starting, and use function "A058" to specify the DC braking time for starting, regardless of the braking mode selection (edge or level mode). (See examples 4-a and 4-b.)

Set the braking force for periods other than starting by using the DC braking force setting (A054).

Set the output frequency at which to start DC braking by using the DC braking frequency setting (A052). When you set the DC braking wait time (A053), the inverter output will be shut off when the output frequency reaches the setting of "A052" after the operation command (FW signal) is turned off, and the motor will run freely for the delay time set by "A053". DC braking will be started after the delay (A053). The internal DC braking operation to be performed when the operation command is switched from the stop command to the start command varies depending on the braking mode (edge or level mode).

Edge mode: The DC braking time setting (A055) is given priority over operation commands, and the inverter performs DC braking according to the setting of "A055". When the output frequency reaches the setting of "A052" the inverter performs DC braking for the time set for "A055". Even if the stop command is input during DC braking, DC braking continues until the time set for "A055" elapses. (See examples 5-a and 6-a.)

Level mode: Operation commands are given priority over the DC braking time setting. The inverter follows operation commands, regardless of the DC braking time setting (A055). If the start command is input during DC braking, the inverter starts the normal motor operation, regardless of the DC braking time setting (A055). (See examples 5-b and 6-b.)

(a) Edge mode				(b) Level mode
i) (Example 4-a) when the start command is input:			i) (Example 4-b) when the start command is input:
FW			FW
Output			Output
frequency			frequency
A057				A057
	A058			A058
ii) (Example 5-a) when the stop command is input:			ii) (Example 5-b) when the stop command is input:
FW			FW
Output		Free running	Output	Free running
frequency			frequency
A052	A053	A055		A053	A055
				A052
ii) (Example 6-a) when the stop command is input:			ii) (Example 6-b) when the stop command is input:

FW FW

Output	Output
frequency	frequency
A055	A055
A052	A052

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