Lenze i700 - Manual (Page 248)

8 Monitoring functions
8.4 Monitoring of the motor utilisation (I²xt)
248
Lenze · i700 servo inverter · Reference manual · DMS 1.5 EN · 03/2014 · TD05
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
8.4.2 UL 508-compliant I²xt motor overload monitoring
If the compliance with the UL 508 standard is required for the operation of the motor and the UL
508 compliant motor load monitoring is implemented by the mathematical model of the I²xt
monitoring, the following conditions have to be met.
UL 508 condition 1:
With a motor load of 600 %, the I²xt warning has to be output within 20 seconds.
• A motor load of 600 % occurs if the r.m.s. value of the total motor current displayed in the object
0x2DD1:5 (or 0x35D1:5 for axis B) corresponds to 6 times the rated motor current ( 0x6075 or
0x6875 for axis B).
This condition can be met by the following parameter setting:

Note!
The settings described have been taken from the current UL 508 standard. If the UL 508
standard is changed, the parameter setting has to be adapted.
The i700 servo inverter only outputs one warning if the warning limit has been exceeded
( 0x2D4E or 0x354E for axis B). The i700 servo inverter cannot interrupt the operation of
the motor. The motor load has to be interrupted by a higher-level Controller.

Stop!
From version 01.04 onwards:
If the disconnection must not or cannot be executed by a higher-level Controller, the
operation has to be interrupted by the following parameter setting:
1. Set the response "1: Fault" to the excess of the adjustable error threshold in the object
0x2D50:1 (or 0x3550:1 for axis B).
2. Set the threshold value as error threshold which in case of being exceeded triggers an
interruption of the operation in the object 0x2D50:2 (or 0x3550:2 for axis B).
Object Name Setting
Axis A Axis B
0x2D4C:2 0x354C:2 Motor utilisation (I²xt): Thermal time constant - laminations ≤ 709 s
0x2D4C:3 0x354C:3 Motor utilisation (I²xt): Influence of the winding 0 %
0x2D4E 0x354E Motor utilisation (I²xt): Motor overload warning threshold 100 %
From version 01.04 onwards:
0x2D50:1 0x3550:1 Motor utilisation (I²xt): Response 1: Fault
0x2D50:2 0x3550:2 Motor utilisation (I²xt): Error threshold 100 %