ABB 615 Series - Function Block

4.9.2 Function block
A070389 V3 EN
Figure 370: Function block
4.9.3 Functionality
The arc protection function AFD detects arc situations in air insulated metal-clad
switchgears caused by, for example, human errors during maintenance or insulation
breakdown during operation.
The function detects light from an arc either locally or via a remote light signal. The
function also monitors phase and residual currents to be able to make accurate decisions
on ongoing arcing situations.
The function contains a blocking functionality. Blocking deactivates all outputs and resets
timers.
4.9.4 Operation principle
The function can be enabled and disabled with the Operation setting. The corresponding
parameter values are “Enable” and “Disable”.
The operation of AFD can be described by using a module diagram. All the modules in the
diagram are explained in the next sections.
1MAC059074-MB A Section 4
Protection functions
615 series ANSI 741
Technical Manual