Mttf, 1ܯܶܶܨ, 1 ܯܶܶܨ – BECKHOFF TwinSAFE User Manual
Page 90: ሺܮ݄݅ܿݐݒݎ݄ܽ݊݃ሻ 1 ܯܶܶܨ, ሺܭ1ሻሻ, ܯܶܶܨ, ሺk1ሻ ൌ ܤ10, ሺܭ1ሻ 0.1 כ, כ 8760
Circuit examples
88
Application Guide TwinSAFE
as:
1
ܯܶܶܨ
ௗ ௧௧
ൌ
1
ܯܶܶܨ
ௗ
ሺܮ݄݅ܿݐݒݎ݄ܽ݊݃ሻ
1
ܯܶܶܨ
ௗ
ሺܧܮ1904ሻ
1
ܯܶܶܨ
ௗ
ሺܧܮ6900ሻ
1
ܯܶܶܨ
ௗ
ሺܧܮ2904ሻ
1
ሺܯܶܶܨ
ௗ
ሺܭ1ሻሻ
with:
ܯܶܶܨ
ௗ
ሺK1ሻ ൌ
ܤ10
ௗ
ሺܭ1ሻ
0.1 כ ݊
If only PFH values are available for EL1904 and EL6900, the following estimation applies:
ܯܶܶܨ
ௗ
ሺELxxxxሻ ൌ
ሺ1 െ ܦܥሺܧܮݔݔݔሻሻ
ܲܨܪሺܧܮݔݔݔሻ
Hence:
ܯܶܶܨ
ௗ
ሺEL1904ሻ ൌ
൫1 െ ܦܥሺܧܮ1904ሻ൯
ܲܨܪሺܧܮ1904ሻ
ൌ
ሺ1 െ 0.99ሻ
1.11E െ 09
ଵ
୦
כ 8760
୦
୷
ൌ
0.01
9.72E െ 06
ଵ
୷
ൌ 1028.8y
ܯܶܶܨ
ௗ
ሺEL6900ሻ ൌ
ሺ1 െ ܦܥሺܧܮ6900ሻሻ
ܲܨܪሺܧܮ6900ሻ
ൌ
ሺ1 െ 0.99ሻ
1.03E െ 09
ଵ
୦
כ 8760
୦
୷
ൌ
0.01
9.02E െ 06
ଵ
୷
ൌ 1108.6y
ܯܶܶܨ
ௗ
ሺEL2904ሻ ൌ
ሺ1 െ ܦܥሺܧܮ2904ሻሻ
ܲܨܪሺܧܮ2904ሻ
ൌ
ሺ1 െ 0.99ሻ
1.25E െ 09
ଵ
୦
כ 8760
୦
୷
ൌ
0.01
1.1E െ 05
ଵ
୷
ൌ 913.2y
ܯܶܶܨ
ௗ
ሺ
Light curtainሻ ൌ
൫1 െ ܦܥሺܮ݄݅݃ݐ ܿݑݎݐܽ݅݊ሻ൯
ܲܨܪሺܮ݄݅݃ݐ ܿݑݎݐܽ݅݊ሻ ൌ
ሺ1 െ 0.99ሻ
1.50E െ 08
ଵ
୦
כ 8760
୦
୷
ൌ
0.01
1.31E െ 04
ଵ
୷
ൌ 76.1y
MTTF
d tot
=
ଵ
భ
ళల.భ
ା
భ
భబమఴ.ఴ
ା
భ
భభబఴ.ల
ା
భ
వభయ.మ
ା
భ
మవర.ర
ൌ 51.3ݕ
DC
avg
=
వవ%
ళల.భ
ା
వవ%
భబమఴ.ఴ
ା
వవ%
భభబఴ.ల
ା
వవ%
వభయ.మ
ା
వవ%
ఱఴఴ.ళ
ା
వవ%
మవర.ర
భ
ళల.భ
ା
భ
భబమఴ.ఴ
ା
భ
భభబఴ.ల
ା
భ
వభయ.మ
ା
భ
ఱఴఴ.ళ
ା
భ
మవర.ర
ൌ 99.0%