Parker EY Series, Техническое руководство

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18 – Pvd3675_Gb_Ey_Septembre_2017
3.1.6. Current limitation at stall conditions (i.e. speed < 3 rpm)
Recommended reduced current at speed < 3 rpm:
0 0
* 0.7 *
2
1
I I I
reduced
≅ =
Warning: The current must be limited to the prescribed values. If the
nominal torque has to be maintained at stop or low speed (< 3 rpm),
imperatively limit the current to 70% of I
0
(permanent current at low
speed), in order to avoid an excessive overheating of the motor.
Please refer to the drive technical documentation for any further
information and to choose functions to program the drive.
3.1.7. Peak current limitation
It is possible to use the EY motors with a current higher than the permanent current.
However, to avoid any overheating, the following rules must be respected.
1) The peak currents and peak torques given in the data sheet must never be
exceeded.
2) The thermal equivalent torque must be respected (§3.1.4).
3) If 1) and 2) are respected (it can limit the peak current value or duration), the
peak current duration ( tp ) must be limited, in addition, accordingly to the
following table (Io is the permanent current at low speed).
I
pi
/Io =2 I
pi
/Io = 3 I
p
/Io = 4 I
pi
/Io >5
EY310
tp<0.8 s tp<0.3s tp<0.15s tp<0.1s
EY420
EY430
EY620
tp<1.5s tp<0.6s tp<0.3s tp<0.2s
EY630
EY820
EY840
EY860
The peak current duration is calculated for a temperature rise of 3°C
Consult us for more demanding applications.
0
1
2
3
4
0 5 10 15 20 25
Pea
k
cu
rr
en
t/
Lo
w
sp
eed
cu
rre
nt
Time
I/Io
tp
tc