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FUNCTION CHARACTERISTICS
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Arc Flash Protection
Preface
An Arc Flash or an Electric Arc is the rapid and dangerous release of energy due to an electrical ar-
cing fault. It happens in a fraction of a second – even faster that you can blink your eye and can have
devastating consequences for anyone exposed.
The intensity of the Arc Flash is influenced not only by the voltage. An Arc Flash will contain the
release of thermal energy, acoustical energy, pressure wave and debris.
Operation and settings
Two different types of light sensor are proposed:
• Loop type, it is used when it’s necessary catch the flash light over a close path
• Covered fibre type with optical lens on termination in order to catch a relevant flash light
target
Light sensors are connected to arc flash card by P.O.F. (Plastic Optical Fibre) and each sensor is
controlled by a dedicated diagnostics.
Protection function and each element can be enabled separtely; every light sensor corresponds
to dedicated protection element, its relevant start and/or trip, always instantaneous and never de-
layable, could be related to overcurrent event and/or to activation of any digital inputs. In case of
overcurrent it’s possible choice between phase current and residual current.
Every element must be able to activate one or more LED and one or more available digital output;
delay reset is set up to 250 ms.
Breaker failure (BF)
Each thresholds can be associated to BF (H) and BF (L) protection by activating the relative param-
eter in the matrices “Selection of function tripping for BF (H)” or “Selection of function tripping for
BF (L)” in relevant
BF
menus:
• Set \ Profile A (or B) \ Breaker failure - BF side H
• Set \ Profile A (or B) \ Breaker failure - BF side L
Logical block (Block1)
If Arc Flash enabling parameters is set to ON and the dedicated binary input is designed for logical
block (Block1), the protection is blocked whenever the given input is active.
K2
K3
S3
S2
S1
BI1
K3
HSO
K1
Zona 1
Zona 2
Zona 3
K3
S3
S2
S1
Zona 1
Zona 2
Zona 3
K3
S3
S2
S1
Zona 1
Zona 2
Zona 3
K3
S3
S2
S1
Zona 1
Zona 2
Zona 3
HSO
K1
K1
K1 (CBF)
K1 (CBF)
K1 (CBF)
BI1
BI1
BI1
K4
K2
K3
S3
S2
S1
BI1
K3
HSO
K1
Zona 1
Zona 2
Zona 3
K3
S3
S2
S1
Zona 1
Zona 2
Zona 3
K3
Zona 1
Zona 2
Zona 3
K3
Zona 1
Zona 2
Zona 3
HSO
K1 (CBF)
BI1
BI1
K4
S3
S2
S1
HSO
BI1
S3
S2
S1
HSO
K1 (CBF)
K1 (CBF)
XMR-D EQUIPMENT MANUAL
Ed. 2.9 - 02/2021