Lenze ECSCAxxx - Manual (Page 34)

Safety instructions
Thermal motor monitoring
Self−ventilated motors
2
l
34 EDBCSXA064 EN 3.2
2.2.2 Self−ventilated motors
Due to the construction, self−ventilated standard motors are exposed to an increased heat
generation in the lower speed range compared to forced ventilated motors.
J
Warnings!
For complying with the UL 508C standard, you have to set the
speed−dependent evaluation of the permissible torque via code C0129/x.
Parameter setting
The following codes can be set for I 2 x t monitoring:
Code Meaning Value range Lenze setting
C0066 Display of the I 2 x t load of the motor 0 ... 250 % −
C0120 Threshold: Triggering of error "OC6" 0 ... 120 % 0 %
C0127 Threshold: Triggering of error "OC8" 0 ... 120 % 0 %
C0128 Thermal motor time constant 0.1 ... 50.0 min 5.0 min
C0606 Response to error "OC8" TRIP, warning, off Warning
C0129/1 S1 torque characteristic I
1
/I
rated
10 ... 200 % 100 %
C0129/2 S1 torque characteristics n
2
/n
rated
10 ... 200 % 40 %
Effect of code C0129/x
0
0.9
0 0.1
C0129/2
0.2 0.3 0.4
0.6
0.7
0.8
1.0
1.1 1
0
0.132
2
I / IN
n / nN
C0129/1
3
9300STD350
Fig. 2−2 Working point in the range of characteristic lowering
The lowered speed / torque characteristic (Fig. 2−2) reduces the permissible thermal load
of self−ventilated standard motors. The characteristic is a line the definition of which
requires two points:
ƒ Point
0: Definition with C0129/1
This value also enables an increase of the maximally permissible load.
ƒ Point
1: Definition with C0129/2
With increasing speeds, the maximally permissible load remains unchanged
(I
Mot
= I
rated
).
In Fig. 2−2, the motor speed and the corresponding permissible motor torque ( 3) can be
read for each working point (
2on the characteristic (0) ... 1). 3 can also be calculated
using the values in C0129/1and C0129/2 (evaluation coefficient "y",
¶ 35)