Lenze EVS9332xS - Manual (Page 29)

Safety instructions
Thermal motor monitoring
Forced ventilated or naturally ventilated motors
2
2.2
2.2.1
l
2.2−2 EDSVS9332S EN 6.0−07/2013
2.2.1 Forced ventilated or naturally ventilated motors
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
Formula for release time Information
t + * ( t ) ln
ȧȧ
ȡ
Ȣ
1 * z ) 1
ǒ
IMot
IN
Ǔ
2
100
ȧȧ
ȣ
Ȥ
I
Mot
Actual motor current (C0054)
I
r
Rated motor current (C0088)
t Thermal motor time constant (C0128)
z Threshold value in C0120 (OC6) or
C0127 (OC8)
Formulae for I 2 x t load Information
L(t) +
ǒ
I
Mot
I
N
Ǔ
2
100%
ǒ
1 * e
*t
t
Ǔ
L(t) Chronological sequence of the I 2 x t
load of the motor
(Display: C0066)
I
Mot
Actual motor current (C0054)
Ir Rated motor current (C0088)
t Thermal motor time constant (C0128)
If the controller is inhibited, the I 2 x t load is reduced:
L(t) + L
Start
e * tt
Ǹ
L
Start
I 2 x t load before controller inhibit
If an error is triggered, the value
corresponds to the threshold value set
in C0120 (OC6) or C0127 (OC8).
Diagram for detecting the release times for a motor with a thermal motor
time constant of 5 minutes (Lenze setting C0128):
I = 3 × I
Mot N
0
50
100
120
0 100 200 300 400 500 600 700 800 900 1000
t [s]
L [%] I = 2 × I
Mot N
I = 1.5 × I
Mot N
I = 1 × I
Mot N
9300STD105
Fig. 2.2−1 I 2 × t−monitoring: Release times for different motor currents and trigger
thresholds
I
Mot
Actual motor current (C0054)
I
r
Rated motor current (C0088)
L I 2 x t load of the motor (display: C0066)
T Time
Parameter setting
Calculate release time and
I
2 xt load
Read release time in the
diagram