Siemens 1FT7 Configuration Manual

Technical data and characteristic curves
4.1 Operating range and characteristics
1FT7 Synchronous Motors
76 Configuration Manual, (PFT7S) 01/2009, 6SN1197-0AD13-0BP2
Shifting the voltage limiting characteristic curve (only relevant when field weakening is deactivated)
In order to identify the limits of the motor for a converter output voltage (U
mot
) other than 380
V or 425 V, the relevant voltage limiting characteristic curve must be shifted (offset) for the
particular new output voltage (U
mot new
).
NOTICE
The offset of the voltage limiting characteristic only applies for linear limiting characteristics,
e.g. for 1FT7 Compact motors. The voltage limiting characteristic can be offset only if the
condition U
mot new
> U
iN
is fulfilled.
Read the induced voltage U
iN
from the motor rating plate or calculate it from the
characteristic curve: U
iN
= k
E
∙ n
N
/ 1000
The degree of offset is obtained as follows:
For an output voltage of U
mot, new
, an offset is obtained along the X axis (speed) by a factor of:
U
mot, new
= new converter output voltage
PRWQHZ
0RW
8
8
U
mot
= converter output voltage from the characteristic curve for 380 V or
425 V
Calculating the new limit torque with the new limiting characteristic
0


0RW
1HZFRQYHUWHURXWSXWYROWDJH8
&RQYHUWHURXWSXWYROWDJH8
0RWQHZ
3
/LPLW
6.
7KHUPDOOLPLWLQJFKDUDFWHULVWLF
Q>USP@
0>1P@
3
Q
3
Q
Q
1
0
/LPLWQHZ
3
Figure 4-4 Offset of voltage limiting characteristic from U
mot
to U
mot new

Siemens 1FT7 Specifications

General

Brand	Siemens
Model	1FT7
Category	Engine
Language	English