User`s manual

535 User's Manual Chapter 7 75
Applications
TIME
ICON OFF
NO ALARM
IN ALARM
CONDITION
MAY
ACKNOWLEDGE
RELAY
ENERGIZED
RELAY
DE-ENERGIZED
ICON ON
RELAY
DE-ENERGIZED
ICON OFF
NO ALARM
PV
DB
A.SP
PARAMETER SETTINGS:
OUTPUT N = ALM.RLY:ON (N = 2 to 4)
ALM. TYPE:1 = HIGH ALRM.
ALM.:1 OUT. = N (N = 2 to 4)
LATCHING = NO LATCH
ACK.:1 = ENABLED
TIME
ALARM
CONDITION
RELAY
ENERGIZED
RELAY
ENERGIZED
ICON ON
PV
A.SP
UNIT
POWER UP
RELAY
ENERGIZED
ICON ON
DB
MAY
ACKNOWLEDGE
ICON ON
MAY
ACKNOWLEDGE
CANNOT
ACKNOWLEDGE
PARAMETER SETTINGS:
OUTPUT N = ALM.RLY:ON (N = 2 to 4)
ALM. TYPE:1 = HIGH ALM.
ALM.:1 OUT. = N (N = 2 to 4)
LATCHING:1 = LATCH
ACK.:1 = DISABLED
POWER UP:1 = ALARM
PARAMETER SETTINGS:
OUTPUT N = ALM.RLY:ON (N = 2 to 4)
ALM. TYPE:1 = DEVIATION
ALM.:1 OUT. = N (N = 2 to 4)
LATCHING = LATCH
ACK.:1 = ENABLED
ALARM SP:1 = (<0)
TIME
IN ALARM
CONDITION
MAY
ACKNOWLEDGE
RELAY
ENERGIZED
RELAY
DE-ENERGIZED
ICON ON
MUST
ACKNOWLEDGE
TO SHUT OFF
ICON AND
DE-ENERGIZE
RELAY
ICON OFF
NO ALARM
PV
C.SP
+ A.SP
DB
C.SP
TIME
ICON ON
IN ALARM
CONDITION
CANNOT
ACKNOWLEDGE
RELAY
DE-ENERGIZED
RELAY
ENERGIZED
ICON ON
RELAY
DE-ENERGIZED
ICON OFF
PV
ICON OFF
RELAY
ENERGIZED
NO ALARM
NO ALARM CANNOT
ACKNOWLEDGE
C.SP
+ A.SP
C.SP
DB
C.SP
- A.SP
DB
IN ALARM
CONDITION
PARAMETER SETTINGS:
OUTPUT N = ALM.RLY:OFF (N = 2 to 4)
ALM. TYPE:1 = BAND
ALM.:1 OUT. = N (N= 2 to 4)
LATCHING = NO LATCH
ACK.:1 = DISABLED
BAND ALARM HIGH PROCESS VARIABLE ALARM
DEVIATION ALARM POWER UP ALARM
Figure 7.1
Alarm Examples
In example A, the process variable would only have to experience a ten
unit change over a short period of time, while in Example B, it would re-
quire a 100 unit change over a ten second period. Example A is much
more sensitive than Example B. In general, for a given rate-of-change,
the shorter the time period, the more sensitive the rate alarm.