Siemens SIPROTEC 7SJ62 Instruction Manual

Functions
6-1097SJ62 Manual
C53000-G1140-C121-1
the difference between the number of allowable cold and warm starts is entered at ad-
dress  &2/'²:$50.
For motors without separate ventilation, the reduced cooling at motor stop can be ac-
counted for by entering the Nτ²)$&725 at address . As soon as the current no
longer exceeds the current flow monitoring setting entered at address , the time
constant is increased by the kτ factor.
If no difference between the time constants is to be used (e.g. externally-ventilated
motors), then the Nτ²)$&725 should be set to .
Example
: Motor with the following data:
Nominal Voltage V
N
= 6600 V
Nominal Current I
N
= 126 A
Starting Current I
Start
= 624 A
Starting Duration @ I
Start
T
ANL max
= 8.5 s
Allowable Starts with Cold Motor n
cold
= 3
Allowable Starts with Warm Motor n
warm
= 2
Current Transformer Ratio 200 A/1 A
The following settings are derived from these data:
The following settings are made:
I
Start
/I
N
= 4.9
I
N
= 0.6 A
Warm Starts = 2
Cold Starts – Warm Starts = 1
6.10.2.1 Settings for Start Inhibit of Motors
In the list below, the setting range and default setting value for Address 4305 are for
a device with a nominal current rating I
N
= 5 A. For a nominal current rating I
N
= 1 A,
divide the Setting Options values and Default Setting value by 5. Consider the current
transformer ratios when setting the device with primary values.
I
START
I
N
⁄
624 A
126 A
---------------
4.95
==
I
N
126 A
200 A
---------------
0.62 I
NCTsec
⋅
==
Addr. LCD-Text Setting Options Default
Setting
Comments
4301 FCT 66 OFF
ON
OFF 66 Startup Counter for Motors
4302 IStart/IMOTnom 3.0 ~ 10.0 4.5 I Start / I Motor nominal
4303 T START MAX. 3
~ 120 sec 10 sec Maximum Permissible Starting Time
4304 T Equal 0.0
~ 60.0 min 1.0 min Rotor Temperature Equilibrium Time
www . ElectricalPartManuals . com

Siemens SIPROTEC 7SJ62 Specifications

General

Brand	Siemens
Model	SIPROTEC 7SJ62
Category	Relays
Language	English