Siemens 125-3208 operating instructions Motor Current Flying Start, Search Rate Flying Start

SED2 VFD Electronic Bypass Option Operating Instructions

Parameter	Description			Action	Setting/
					Default
P1202	Motor Current: Flying Start	1.	Press	to enter the SED2	Minimum = 10
					Default = 100
	Defines search current used for		parameter mode and to display		Maximum =
	flying start. Value is in % based		r0000.		200
	on the rated motor current
	(P0305).	2.	Press	to advance to
			parameter P1202.
		3.	Press	to access the
			parameter values level.
		4.	Press	to advance to
			desired value.
		5.	Press	to confirm and save
			the setting.

NOTE:

Reducing the search current may improve performance for flying start if the inertia of the system is not very high.

P1203	Search Rate: Flying Start	1.	Press	to enter the SED2	Minimum = 10
					Default = 100
	Sets factor by which the output		parameter mode and to display		Maximum =
			r0000.
	frequency changes during flying				200
	start to synchronize with the
	turning motor. This value,	2.	Press	to advance to
	entered in % relative to the
			parameter P1203.
	default time factor, defines the
	initial gradient and influences the
	time taken to search for the	3.	Press	to access the
	motor frequency.
			parameter values level.
	The search time is the time taken
	to search through all frequencies	4.	Press	to advance to
	between		desired value.
	f_max + 2 × f_slip to 0 Hz.
		5.	Press	to confirm and save
			the setting.

NOTES:

1. P1203 = 100% is defined as giving a rate of 2% of f_slip, nom/ms.

2. P1203 = 200% would result in a rate of frequency change of 1% of f_slip, nom/ms.

3. A higher value produces a flatter gradient, and thus a longer search time. A lower value has the opposite effect.

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