63230-300-212 Chapter5—Input/Output C apabilities
April 2001 Relay Output Operating Modes
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© 2001 Schneider Electric All Rights Reserved
Beforewe describe the 11 available relay operatingmodes, it is important to
understand thedifference between a relay configured for remote (external)
control and a relayconfigured for circuit monitor (internal) control.
Each relay outputdefaults to external control, but you can choosewhether
the relayis set to external or internal control:
•Remote(external) control—the relayis controlled either from a PC using
SMSor a programmable logic controller using commands via
communications.
•Circuit monitor(internal) control—the relay is c ontrolled by the circ uit
monitorin response to a set-point controlledalarm condition, or as a pulse
initiatoroutput. Once you’ve set up a relay for circuit monitorcontrol, you
can no longer operatethe relay remotely. However,you can temporarily
overridethe relay, using SMS.
NOTE: Ifany basic setup parameters or I/O setup parametersare modified,
all relayoutputs will be de-energized.
The 11 relay operatingmodes are as follows:
•Normal
—
Remotely Controlled:
Energize therelay by issuing a command from
aremote PC or programmable controller.The relay remains energized
until a command tode-energize is issued from the remote PC or
programmablecontroller, or until the circuit monitor loses control
power.When control power is restored, the relay will be re-energized.
—
Circuit MonitorControlled:
When an alarm condition assignedto the
relayoccurs, the relay is energized.The relay is not de-energized until
all
alarmconditions assigned to the relay have droppedout, the circuit
monitorloses control power, or the alarms are over-ridden using SMS
software.If the alarm condition is still true when the circuit monitor
regains controlpower, the relay will be re-energized.
•Latched
—
Remotely Controlled:
Energize therelay by issuing a command from
aremote PC or programmable controller.The relay remains energized
until a command tode-energize is issued from a remote PC or
programmablecontroller, or until the circuit monitor loses control
power.When control power is restored, the relay will not be re-
energized.
—
CircuitMonitor Controlled:
When an alarmcondition assigned to the
relayoccurs, the relay is energized. The relay remainsenergized—
evenafter all alarm conditions assigned to the relay have dropped
out—until a command to de-energizeis issued from a remote PC or
programmablecontroller, until the high priority alarm log is cleared
fromthe display, or until thecircuit monitor loses control power.When
controlpower is restored, the relaywill not be re-energized if the alarm
conditionis not TRUE.
RELAY OUTPUTOPERATING MODES