Particulate Alarm; Reset; Remote Reset; Manual Reset - Emerson Net Safety Millennium Reference Manual

Operation
3.3.3

Particulate alarm

When particulate is present in the APM's chamber, the message Alarm displays, the Status
LED blips red, and the current output is 20.0 mA. If the relay has been set to non-latching,
the unit will reset itself; if set to latching, a manual or remote reset is required to clear the
alarm condition. Refer to
Note
The APM may be affected by sudden bursts of infrared light; therefore, it is recommended that a
time delay (between two (2) to five (5) seconds) be put into the monitoring system to prevent
nuisance alarms.
3.4

Reset

3.4.1

Remote reset

The Millennium is capable of remote reset. A normally open push-button switch must be
connected between the RST terminal and the COM terminal on the terminal board. If relay
is set to Latching, a remote reset is possible.
3.4.2

Manual reset

If a relay is set to Latching, a manual reset is required to clear the alarm condition. Simply
place and hold the magnet against the Reed switch or press and hold the setup button for
3-5 seconds. The unit will return to the normal operation.
3.5

Normal

With no particulate present and no fault detected, the display reads Clear, Status LED
blips/blinks green, and the current output is 4.0 mA.
3.6

Outputs

3.6.1

Relays

All relay outputs have FORM-C SPDT contacts rated 5 amperes at 30 Vdc/250 Vac. Relays
are dry contacts.
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Section 3.4.