KEB COMBIVERT F5-A Applications Manual page 154

Setpoint, rotation- and ramp setting
Max. output val. forward (oP.40) / max. output val. reverse (oP.41)
All other limitations (oP.10 / oP.11 "max. reference" and oP.14 / oP.15 "abs. max. reference") limit exclusively
the speed setpoint .
This function is only active if in parameter Ec.42 "encoder alarm mode" the alarm for the used
encoder channel is activated (alarm = on). In vector-controlled operation without speed feedback,
speed limiting is always active.
The state „58: ERROR! Overspeed" (E.OS) is triggered, if ru.07 "actual value display" exceeds either the value
of oP.40 / oP.41 "max. output val." or the value of ru.79 „abs. speed EMC" (only for synchronous motors).
The user defines limits with oP.40/oP.41 that may not be exceeded by the application under any circumstances.
ru.79 shows the maximum speed for a synchronous motor which, if exceeded, leads to an EMC of the motor
high enough to damage the DC-intermediate circuit of the inverter.
Reason for the occurence of excessive speed can be too small a distance between the maximum setpoint and
the speed limit, so that overshoots can trigger the error. Other causes can be (e.g., caused by EMC) malfunc-
tions in the speed measurement or a noisy, insufficiently smoothed speed estimate in the encoderless control
(SCL or ASCL).
Fig. 7.4.5.a
Setpoint [%]
max. setpoint re-
verse
Page 7.4 - 14 COMBIVERT F5-A, -E, -H
Setpoint limits
(oP. 10)
(oP.14)
-100%
+n [rpm]
(oP.11)
-n [rpm]
max. setpoint forward
absolute
point forward
Setpoint [%]
+100%
© KEB, 2012-10
max. set-