Phase Loss Protection- Tile phase loss protection
option will monitor the three-phase electrical system to provide
phase revers;fl and phase loss protection.
PHASE REVERSAL PROTECTION -- If the control sens-
es an incorrect phase relationship, the relay (KI) will be de-
energized (opening its contact). If the phase relationship is
correct, the lelay will be energized. Tile control has a self-
bypass function after a pre-set time. If the control determines
that the three phases stay in a correct lelationship for 10 con-
secutive minutes, the lelay will stay energized reg;udless of the
phase sequence of three inputs as long as 24-vac control
voltage is applied. This self-bypass function will be reset if all
three phases are restored in a phase loss event.
PHASE LOSS PROTECTION-- If the reveLse rotation
bomd senses any one of the three phase inputs has no AC volt-
age, file relay will be deenergized (opening its contact). This
protection is always active as long as 24-vac control voltage is
applied, and is not affected by the self-bypass function of the
phase sequence monitoring function. Howevel: in the event of
phase loss, the relay will be re-energized only if till three phases
me restored and the three phases me in the correct sequence.
A red LED is provided to indicate the function of the board.
See the table below.
LED STATUS FUNCTION
On Continuously Relay contact closed (normal operation).
Relay contact open (phase loss or phase
Blinking reversal has occurred) -- No power will be
supplied to the control system.
Off 24 vac control power net present (off).
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