Lenze 8400 BaseLine C - Page 105

Lenze · 8400 BaseLine C · Reference manual · DMS 1.6 EN · 01/2014 · TD05 105
5 Motor control (MCTRL)
5.8 Monitoring
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
[5-5] Tripping characteristic of the I
2
xt monitoring
Example:
C120 = I
r
/I
rated
x 100 %
C054
= 150 % rated motor current
• After approx. 60 seconds, C066
has reached the final value100 % at output frequencies
f>40Hz.
• The controller outputs the "OC6: I2xt overload motor" error message
and triggers the response
set in C606
(default setting: "Warning").
 Tip!
• If forced ventilated motors are used, a premature response of the overload threshold can
be avoided by deactivating this function if necessary (C606
="0: No Reaction").
• The current limits set in C022
and C023 influence the I
2
xt calculation only in an indirect
way. However, the operation of the motor at maximum possible load can be averted.
Defining current and speed limits
( 76)
f: Output frequency
t: Release time
I
rated
: Rated controller current at a switching frequency of f = 8 kHz
I
r
: Rated motor current (see nameplate of motor)
C054
: Apparent motor current
C120
: Motor overload threshold
60
180
240
300
360
t [s]
0.5
0
0
1.0
1.5 2.0
C00054
I
r
120
f=0Hz
f=20Hz
f>40Hz
I x 100 %
I
r
N
C00120 <
I x 100 %
I
r
N
C00120 =
I x 100 %
I
r
N
C00120 >