5-176 B30 Bus Differential System GE Multilin5.8 INPUTS AND OUTPUTS 5 SETTINGS55.8.3 CONTACT OUTPUTSa) DIGITAL OUTPUTSPATH: SETTINGS INPUTS/OUTPUTS CONTACT OUTPUTS CONTACT OUTPUT H1Upon startup of the relay, the main processor will determine from an assessment of the modules installed in the chassiswhich contact outputs are available and present the settings for only these outputs.An ID may be assigned to each contact output. The signal that can OPERATE a contact output may be any FlexLogic oper-and (virtual output, element state, contact input, or virtual input). An additional FlexLogic operand may be used to SEAL-INthe relay. Any change of state of a contact output can be logged as an Event if programmed to do so.For example, the trip circuit current is monitored by providing a current threshold detector in series with some Form-A con-tacts (see the trip circuit example in the Digital elements section). The monitor will set a flag (see the specifications forForm-A). The name of the FlexLogic operand set by the monitor, consists of the output relay designation, followed by thename of the flag; for example, CONT OP 1 ION.In most breaker control circuits, the trip coil is connected in series with a breaker auxiliary contact used to interrupt currentflow after the breaker has tripped, to prevent damage to the less robust initiating contact. This can be done by monitoringan auxiliary contact on the breaker which opens when the breaker has tripped, but this scheme is subject to incorrect oper-ation caused by differences in timing between breaker auxiliary contact change-of-state and interruption of current in thetrip circuit. The most dependable protection of the initiating contact is provided by directly measuring current in the trippingcircuit, and using this parameter to control resetting of the initiating relay. This scheme is often called trip seal-in.This can be realized in the B30 using the CONT OP 1 ION FlexLogic operand to seal-in the contact output as follows:CONTACT OUTPUT H1 ID: “Cont Op 1"OUTPUT H1 OPERATE: any suitable FlexLogic operandOUTPUT H1 SEAL-IN: “Cont Op 1 IOn”CONTACT OUTPUT H1 EVENTS: “Enabled”b) LATCHING OUTPUTSPATH: SETTINGS INPUTS/OUTPUTS CONTACT OUTPUTS CONTACT OUTPUT H1a CONTACT OUTPUT H1CONTACT OUTPUT H1 IDCont Op 1Range: Up to 12 alphanumeric charactersMESSAGE OUTPUT H1 OPERATE:OffRange: FlexLogic operandMESSAGE OUTPUT H1 SEAL-IN:OffRange: FlexLogic operandMESSAGE CONTACT OUTPUT H1EVENTS: EnabledRange: Disabled, Enabled CONTACT OUTPUT H1aOUTPUT H1a IDL-Cont Op 1Range: Up to 12 alphanumeric charactersMESSAGE OUTPUT H1a OPERATE:OffRange: FlexLogic operandMESSAGE OUTPUT H1a RESET:OffRange: FlexLogic operandMESSAGE OUTPUT H1a TYPE:Operate-dominantRange: Operate-dominant, Reset-dominantMESSAGE OUTPUT H1a EVENTS:DisabledRange: Disabled, Enabled
