Installation Manual

INS_FDC80_REV–
12/29/11
PAGE 6
APPLICATION NOTE
INSTALLATION AND OPERATION MANUAL FDC80
TECH SUPPORT: 1.888.678.9427
LATCHING RELAYS:
Latching relays are typically used when the application must insure that the contact outputs will not change state when either power
is lost or the fiber is broken. This is a common requirement at high security gate entrance locations, where the gates must not open
under any abnormal operating condition. In other words, they must open ONLY when commanded via the contact input state. Alarm
conditions detected by the wire supervision circuits will therefore leave the relays in their current state.
NON-LATCHING RELAYS:
Non-latching relays are utilized if the contact outputs must switch to a known state when the power is lost or the fiber is broken. This
is a common requirement in applications that require a known failsafe state during abnormal operating conditions. Alarm conditions
detected by the wire supervision circuits will therefore leave the relays in their default failsafe state.