Tempco TEC-9300, Инструкция по эксплуатации, Страница: 34 / 92

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Normal Alarm: A1MD=NORM
When a normal alarm is selected, the
alarm output is de-energized in the
non-alarm condition and energized in
an alarm condition.
Latching Alarm: A1MD=LTCH
If a latching alarm is selected, once the
alarm output is energized, it will
remain unchanged even if the alarm
condition is cleared. The latching
alarms are disabled when the power is
shut off or if event input is applied
with proper selection of EIFN.
Holding Alarm: A1MD=HOLD
A holding alarm prevents an alarm
from powering up. The alarm is
enabled only when the process reaches
the set point value (may be SP1 or
SP2, see section 4-1 event input).
Afterwards, the alarm performs the
same function as a normal alarm.
Latching/Holding Alarm: A1MD=LT.HO
A latching/holding alarm performs both holding and latching function.
3–8 Process Alarms
There are at most two independent alarms available by
adjusting OUT2. If AL2 is selected for OUT2, then
OUT2 will perform alarm 2 function. Now NONE can’t
be selected for A2FN, otherwise Er06 will be displayed.
A process alarm sets an absolute trigger level (or temper-
ature). When the process (could be PV1, PV 2, or PV1-
PV2) exceeds that absolute trigger level, an alarm occurs.
A process alarm is independent from the set point. Adjust
A1FN (Alarm 1 function) in the setup menu. One of
eight functions can be selected for process alarm. These
are: PV1.H, PV1.L, PV2.H, PV2.L, P1.2.H,
P1.2.L, D1.2.H, D1.2.L. When PV1.H or PV1.L is select-
ed, the alarm examines the PV1 value. When PV2.H or
PV2.L is selected, the alarm examines the PV2 value.
When P1.2.H or P1.2.L is selected, the alarm occurs if
the PV1 or PV2 value exceeds the trigger level. When
D1.2.H or D1.2.L is selected, the alarm occurs if the
PV1-PV2 (difference) value exceeds the trigger level.
The trigger level is determined by A1SP (Alarm 1 set
point) and A1HY (Alarm 1 hysteresis value) in User
Menu for alarm 1. The hysteresis value is introduced to
avoid interference action of alarm in a noisy environ-
ment. Normally A1HY can be set with a minimum (0.1)
value. A1DV and/or A2DV are hidden if alarm 1 and/or
alarm 2 are set for process alarm.
8 Types of Process Alarms:
PV1.H, PV1.L, PV2.H, PV2.L,
P1.2.H, P1.2.L, D1.2.H, D1.2.L
Process Alarm 1
Setup: A1FN, A1MD
Adjust: A1SP, A1HY
Trigger level=A1SP±A1HY
Process Alarm 2
Setup: OUT2, A2FN, A2MD
Adjust: A2SP, A2HY
Trigger level=A2SP±A2HY
Reset Latching alarm
1. Power off
2. Apply event input in accordance
with proper selection of EIFN
Although the descriptions in the examples below are based on alarm 1, the same conditions can be applied to alarm 2.