91 - PVD 3622_GB_TM_January 2014.Docx
3.7. Thermal Protection
Protection against thermal overloading of the motor is provided by 2 x 3 PTC
thermistors and one KTY temperature sensor (and one more in case of KTY failure)
built into the stator winding as standard. The thermal sensors, due to their thermal
inertia, are unable to follow very fast winding temperature variations. They acheive
their thermal steady state after a few minutes.
Warning: To protect correctly the motor against very fast overload,
please refer to 3.1.6. Peak current limitations
Both PTC thermistors and KTY sensor are connected through the terminal box,
according to the electrical connection diagrams.
3.7.1.
Alarm tripping with PTC thermistors :
Two thermal probes (PTC thermistors) fitted in the servomotor winding trip the
electronic system at
140° and 150°
5° C
. When the rated tripping temperature is
reached, the PTC thermistor undergoes a step change in resistance. This means that
a limit can be easily and reliably detected by the drive.
The graph and tab below
shows
PTC
sensor
resistance as a function of
temperature
(T
N
is nominal temperature)
Temperature
Resistance
value
-20°C up to T
N
-20°C
R≤750Ω
TNF-5°C
R≤1650Ω
TNF+5°C
R≥3990Ω
TNF+15°C
R≥12000Ω
PTC 140°C
PTC 150°C
KTY84-130
12000Ω
Resistance (Ω)
399
0Ω
1650Ω
750Ω
T
N
-
2
0
°C
T
N
-
5
°C
T
N
+
5
°C
T
N
+
1
5
°C
Temperature (°C)
-2
0
°C
Summary of Contents for TM Series
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Page 57: ...57 PVD 3622_GB_TM_January 2014 Docx 3 3 1 2 Shaft Height 200 mm Thrust bearing 29424...
Page 61: ...61 PVD 3622_GB_TM_January 2014 Docx 3 3 2 2 Shaft Height 315 mm Thrust Bearing 29426...
Page 62: ...62 PVD 3622_GB_TM_January 2014 Docx 3 3 2 3 Shaft Height 315 mm Thrust Bearing 29430...
Page 66: ...66 PVD 3622_GB_TM_January 2014 Docx 3 3 3 2 Shaft Height 400 mm Thrust Bearing 29434...
Page 67: ...67 PVD 3622_GB_TM_January 2014 Docx 3 3 3 3 Shaft Height 400 mm Thrust Bearing 29440...