Eaton TC 24, Руководство пользователя

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Output 2 can be selected as alarm output. There are 6 types of
alarm functions and one dwell timer can be selected, and four kinds
of alarm modes ( ALMD ) are available for each alarm function.
A process alarm sets two absolute trigger levels. When the process is
higher than SP2, a process high alarm ( PV.HI ) occurs, and the alarm
is off as the process is lower than SP2-O2HY. When the process is
lower than SP2, a process low alarm ( PV.LO ) occurs and the alarm is
off as the process is higher than SP2+O2HY. A process alarm is
independent of set point. A sets two absolute trigger levels. When the process is
higher than SP2, a process high alarm occurs, and the alarm
is off as the process is lower than SP2-O2HY. When the process is
lower than SP2, a process low alarm
occurs and the alarm is
off as the process is higher than SP2+O2HY. A process alarm is
independent of set point.
process alarm
( PV.HI )
( PV.LO )
A deviation alarm alerts the user when the process deviates too far
from set point. When the process is higher than SV+SP2, a deviation
high alarm (DE.HI) occurs and the alarm is off as the process is lower
than SV+SP2-O2HY. When the process is lower than SV+SP2, a
deviation low alarm (DE.LO) occurs and the alarm is off as the process
is higher than SV+SP2+O2HY. Trigger level of deviation alarm is
moving with set point. A alerts the user when the process deviates too far
from set point. When the process is higher than SV+SP2, a deviation
high alarm
occurs and the alarm is off as the process is lower
than SV+SP2-O2HY. When the process is lower than SV+SP2, a
deviation low alarm
occurs and the alarm is off as the process
is higher than SV+SP2+O2HY. Trigger level of deviation alarm is
moving with set point.
deviation alarm
(DE.HI)
(DE.LO)
A deviation band alarm presets two trigger levels relative to set point.
The two trigger levels are SV+SP2 and SV - SP2 for alarm. When the
process is higher than ( SV+SP2 ) or lower than ( SV - SP2 ), a
deviation band high alarm ( DB.HI ) occurs. When the process is within
the trigger levels, a deviation band low alarm (DB.LO) occurs. A presets two trigger levels relative to set point.
The two trigger levels are and for alarm. When the
process is higher than ( SV+SP2 ) or lower than ( SV - SP2 ), a
deviation band high alarm
occurs. When the process is within
the trigger levels, a deviation band low alarm occurs.
deviation band alarm
SV+SP2 SV - SP2
( DB.HI )
(DB.LO)
There are four types of alarm modes available for each alarm function,
these are: Normal alarm, Latching alarm, Holding alarm and Latching/
Holding alarm. They are described as follows: There are four types of alarm modes available for each alarm function,
these are: Normal alarm, Latching alarm, Holding alarm and Latching/
Holding alarm. They are described as follows:
Latching Alarm : ALMD = 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 alarm is reset when the RESET key is pressed, once the alarm
condition is removed. Latching Alarm : ALMD = LTCH
Normal Alarm : ALMD = NORM
When a normal alarm is selected, the alarm output is de-energized
in the non-alarm condition and energized in an alarm condition. Normal Alarm : ALMD = NORM
In the above descriptions SV denotes the current set point value for
control which is different from SP1 as the ramp function is performed. In the above descriptions denotes the current set point value for
control which is different from SP1 as the ramp function is performed.
SV
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