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2 Functions
74
7UM61 Manual
C53000-G1176-C127-3
Figure 2-18
Example of an Unbalanced Load Characteristic Specified by the Machine Man-
ufacturer
Cooldown Time
The parameter
1705
T COOL DOWN
establishes the time required by the protection
object to cool down under admissible unbalanced load
I2>
to the initial value. If the
machine manufacturer does not provide this information, the setting value can be cal-
culated by assuming an equal value for cool-down time and heatup time of the object
to be protected. The formula below shows the relation between the K asymmetry
factor and the cool-down time:
Example:
The following cool-down time results for a K = 20 s and an admissible continual unbal-
anced load
I
2
/
I
N
= 11 %.
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Содержание Siprotec 7UM611
Страница 16: ...Contents 16 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 232: ...2 Functions 232 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 292: ...3 Mounting and Commissioning 292 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 410: ...A Appendix 410 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 412: ...Literature 412 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...