RC Systems ST-72, Instruction Manual

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ST-72 User's Manual
Document: UM-1007 Revision Level A
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2.4.2 ALARM 1 / ALARM 2 / ALARM 3 MENU
The
ALARM MENU
parameters are listed only once, because alarms 1, 2, and 3 are
identical except A1 does not have the option to change the color, it is always yellow,
and only A3 can be turned off if not needed. The following parameters can be accessed
while in the
ALARM MENUS.
Channel 38 Config
Alarm 2
Alarm 3
Fault Alarm
Data From
Linearize
Configure ~
~
~
~
~
~
Alarm 1 ~
Ch. 38 Alarm 3
Latching
Trip On
On Delay (sec)
Off Delay (min)
Horn Drive
Color
Enabled? No
High
0
0
Yes
Red
No
SetPoint 60
Figure 2-15
2.4.2.1 SETPOINT
SETPOINT
is the value where the alarm trips. It is entered in engineering units. For
example, if a channel monitors 0-50 ppmH2S and the alarm must trip at 10 ppm, the
correct entry is 10.00.
2.4.2.2 LATCHING
LATCHING
determines either manual or automatic alarm reset operation.
YES
requires a manual Alarm Reset to unlatch the alarm even though an alarm condition no
longer exists.
YES
also causes this alarm group’s common relay, front panel LED, and
optional discrete relay to latch.
NO
allows all outputs for this alarm to automatically
reset as soon as the alarm condition clears.
2.4.2.3 TRIP ON
TRIP ON
is set to
HIGH
for increasing alarms or
LOW
for decreasing alarms to
determine if the alarm activates upon exceeding or falling below the setpoint.
2.4.2.4 ON/OFF DELAYS
The ON DELAY / OFF DELAY entries allow ON and OFF time delays affecting how
long the setpoint must be surpassed before an alarm event transition occurs. ON delays
are limited to 10 seconds while OFF delays may be as long as 120 minutes. Delays are
useful in many applications to prevent nuisance alarms and unwanted cycling into and
out of alarm conditions.