Page 7.6 - 14 COMBIVERT F5-A, -E, -H © KEB, 2012-10
Motor data and controller adjustments of the synchronous motor
Current offset detection (dr.48 = 19)
The current offset is caused by tolerances of the components in the test circuit and as standard automatically
synchronized in non-energized state (inverter state "nop"). It is necessary in some cases to execute the ad-
justment in power on status by means of current-dependent tolerances in the current detection. For this adjust
parameter dr.48 = 19 and a high frequency AC current is output by the inverter. The rated current of the motor
is injected with a starting frequency of 1kHz. The frequency is automatically reduced if this is not possible.
Furthermore the automatic measurement is deactivated when the modulation is switched off, so the identied
offset remains permanently.
It is recommended to change current offset values only in compliance with KEB.
7.6.3.3.3 Dead time compensation (uf.18)
The drive has also measured the dead time compensation characteristic during automatic identication. The
calibrated characteristic must be activated for the control with motor model by the setting "dead time compen-
sation mode" (uF.18) = 3: „automatic“.
uF.18: dead time compensation mode
Value Explanation
0: off Deactivates the dead time compensation
1: linear Default setting for u/F characteristics open loop operation
2: e function Only required for special applications
3: automatical-
ly
Activation of the identied characteristic. Shall always be used at control of synchronous
motors with motor model
Further available kinds of the dead time compensation are only required for special applications (applications
with high frequencies, some special motors) or in other operating modes (e.g. V/f characteristics controlled).
The dead time compensation can be switched off via a digital input. The digital input is selected with parameter
uF.21. This disconnection is only required for special applications with high frequency.
7.6.3.3.4 motoridenticationerrorstatedr.66
see chapter 7.5.2.3.2 motor identication error state dr.66