Parker TM Series, Technical Manual

Page: 20 / 129

20 - PVD 3622_GB_TM_January 2014.Docx
3.1.5. Current limitation at stall conditions (i.e. speed < 3 rpm)
Recommended reduced current at speed < 3 rpm:
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 80% 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.
3.1.6. Peak current limitations
It is possible to use the TM motor with a current higher than the permanent current.
But, 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 (§3.1.3)
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):
Ip/Io =2 Ip/Io = 3 Ip/Io =4 Ip/Io =5
TMA Tpeak < 4s Tpeak < 1.7s Tpeak < 0.9s Tpeak < 0.5s
Ip/Io =1.5 Ip/Io = 2 Ip/Io =2.5 Ip/Io >2.5
TMW Tpeak < 2s Tpeak < 0.8 Tpeak < 0.5s Not allowed
The peak current duration is calculated for a temperature rise of 3°C
Consult us for more demanding applications.
0
0,5
1
1,5
2
2,5
3
3,5
0 5 10 15 20 25
Peak
c
u
rr
e
n
t/
Low
sp
e
e
d
cu
rr
e
n
t
Time
I/Io
tp
tc