Dwyer 1600 User Manual
Page 25
Rev. 10/98
25
949-1239-3
The following diagram shows the action and reset functions for both
absolute and deviation alarms.
When “Alarm Power Interrupt” ALPi is programmed ON and “Alarm Reset”
is programmed for Hold, the alarm will automatically reset upon a power
failure and subsequent restoration if no alarm condition is present.
If “Alarm Inhibit” ALiH is selected ON, an alarm condition is suspended upon
power up until the process value passes through the alarm set point once.
Alarm inhibit can be restored as if a power up took place by pressing
together the INDEX and ENTER keys for 5 seconds.
W
ARNING
: I
F
INHIBIT
IS
ON
AND
A
POWER
FAILURE
OCCURS
DURING
A
HIGH
ALARM
,
RESTORATION
OF
POWER
WILL
NOT
CAUSE
THE
ALARM
TO
OCCUR
IF
THE
PROCESS
VALUE
DOES
NOT
FIRST
DROP
BELOW
THE
HIGH
ALARM
SETTING
. D
O
NOT
USE
THE
A
LARM
I
NHIBIT
FEATURE
IF
A
HAZARD
IS
CREATED
BY
THIS
ACTION
. B
E
SURE
TO
TEST
ALL
COMBINATIONS
OF
HIGH
AND
LOW
ALARM
INHIBIT
ACTIONS
BEFORE
PLACING
CONTROL
INTO
OPERATION
.
The following Secure menu items apply only to the alarm.
AL
Alarms: Select OFF, Lo, Hi, or HiLo.
OFF
Alarms are turned OFF. No Alarm menu items appear
in the Secondary and Secure menus.
Lo
Low Alarm Only. ALLo appears in the Secondary Menu.
Hi
High Alarm Only. ALHi appears in the Secondary Menu.
HiLo
High and Low Alarms. Both share the same Alarm Relay
output.
OFF
ON
OFF
ON
ON
OFF
ON
OFF
D
ALLo
ALHi
D
D
D
ALLo
ALHi
SP1
SP1
SP1
High Alarm
Low Alarm
High and Low Alarm
DEVIATION ALARMS
OFF
ON
OFF
ON
ON
OFF
ON
OFF
D
ALLo
ALHi
D
D
D
ALLo
ALHi
ABSOLUTE ALARMS