2 thermal utilisation (ixt), 11 drive dimensioning – Lenze DSD User Manual

Page 348

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11

Drive Dimensioning

11.6

Inverters

348

Lenze · Drive Solution Designer · Manual · DMS 4.2 EN · 12/2013 · TD23

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11.6.1.2

Thermal utilisation (Ixt)

For determining the thermal utilisation the required current is evaluated via a device-internal mon-

itoring function. It is simulated for the steady state.

• The momentary current utilisation of the inverter is calculated from the ratio of the required

motor current to the inverter output current available. The inverter output current is reduced

according to the applicable basic conditions.

• The maximum value of the thermal utilisation reflects the monitoring function of the inverter.

[11-19] Inverter diagram: Thermal utilisation

Description

Instantaneous utilisation

Max. value of the thermal utilisation

100 % utilisation

• 100 % corresponds the rated threshold.

Thermal utilisation

• Simulated value, calculated with the time constant of the motor.

I×t pulse utilisation

Performance features

• The performance features can also be found in the selection table.

Selection table ( 355)

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