Table 133: LOVPTUV Non group settings (basic)
Name Values (Range) Unit Step Default Description
GlobalBaseSel 1 - 6 - 1 1 Selection of one of the Global Base Value
groups
7.4.6 Operation principle
The operation of Loss of voltage check LOVPTUV is based on line voltage
measurement. LOVPTUV is provided with a logic, which automatically recognizes if
the line was restored for at least tRestore before starting the tTrip timer. All three
phases are required to be low before the output TRIP is activated. The START output
signal indicates start.
Additionally, LOVPTUV is automatically blocked if only one or two phase voltages
have been detected low for more than tBlock.
LOVPTUV operates again only if the line has been restored to full voltage for at least
tRestore. Operation of the function is also inhibited by fuse failure and open circuit
breaker information signals, by their connection to dedicated inputs of the function
block.
Due to undervoltage conditions being continuous the trip pulse is limited to a length
set by setting tPulse.
The operation of LOVPTUV is supervised by the fuse-failure function (BLKU input)
and the information about the open position (CBOPEN) of the associated circuit
breaker.
The BLOCK input can be connected to a binary input of the IED in order to receive a
block command from external devices or can be software connected to other internal
functions of the IED itself in order to receive a block command from internal
functions. LOVPTUV is also blocked when the IED is in test mode and LOVPTUV
has been blocked from the HMI test menu (Blocked = Yes).
1MRK 511 287-UEN A Section 7
Voltage protection
177
Technical manual
To Next Page
Loading...
Need help?
General
