5motor control (mctrl) – Lenze 8400 StateLine User Manual

Page 240

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5

Motor control (MCTRL)

5.12

Monitoring

240

Lenze · 8400 StateLine · Reference manual · DMS 12.0 EN · 06/2014 · TD05/TD14

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Adjustment of the motor utilisation meter
The motor utilisation meter for indicating the motor load in

C00066

begins to count when the

apparent motor current (

C00054

) is greater than the motor overload setting (

C00120

).

The overload threshold (

C00120

) is to be set as follows:

• If you reduce

C00120

starting from the calculated value, the motor utilisation meter will already

be counted up before the rated overload threshold is reached.

• If you increase

C00120

starting from the calculated value, the motor utilisation meter will not

be counted up until the rated overload threshold is reached.

[5-29] Tripping characteristic of the I

2

xt monitoring

Example in Figure

[5-29]

:

C00120

= I

r

/I

rated

x 100 %

C00054

= 150 % rated motor current

• After approx. 60 seconds,

C00066

has reached the final value (100 %) at output frequencies

f > 40 Hz.

• The controller outputs the "

oC6: I2xt overload motor

" error message and triggers the response

set in

C00606

(default setting: "Warning").

f: Output frequency

t: Release time

I

N

: Rated device current at a switching frequency of f = 8 kHz

I

r

: Rated motor current (see nameplate of motor)

C00054

: Apparent motor current

C00120

: Motor overload setting

C00120

Rated motor current (C00088)

Rated device current (C00098)

------------------------------------------------------------------------------

100 %

=

60

180

240

300

360

t [s]

0.5

0

0

1.0

1.5

2.0

C00054

I

r

120

f = 0 Hz

f = 20 Hz

f > 40 Hz

I x 100 %

I

r

N

C00120 <

I x 100 %

I

r

N

C00120 =

I x 100 %

I

r

N

C00120 >

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