RELAY SENSE
The ‘
Inurt
’ setting refers to the relay sense during powered operation. All other relay output menu settings
refer to the alarm state. When in alarm, the relevant front panel LED is lit.
DEVIATION
If the ‘
dEu
’ action is chosen in the alarm action option, this value determines the amount by which the
PV may change before the alarm is triggered. The value should be in the engineering units.
This menu is only displayed if a current re-transmission output pod is fitted. If ‘
PrESEt
’ is chosen, the output
current can be edited in ‘
LEuEL
’. Otherwise, the re-transmitted current is derived linearly from the
process variable, using ‘
rEt LO
’ and ‘
rEt HI
’.
RE-TRANSMISSION OUTPUT TYPE
The re-transmission can be set to represent rate or total.
OUTPUT SPAN
(4 to 20) mA, (0 to 20) mA or (0 to 10) mA can be selected as the span of the re-transmission.
RE-TRANSMISSION SCALE LOW / HIGH
By entering these values, the user can scale the mA output (selected in
SPAn
) to the PV. Default values
will be equal to the engineering low and engineering high values entered in the input menu.
PRESET mA OUTPUT LEVEL
This is only available if ‘
PrESEt
’ output is chosen.
The relay menu shown is for alarm A. There are two alarms A and B so the menu will be duplicated for
alarm B. The relay menu will only be displayed if a twin relay pod is fitted to the DM3600.
SETPOINT A
The setpoint value defines the engineering value associated with an alarm. For example if an alarm is
required when the flow exceeds 10 000 kg/h, the setpoint will be set to 10 000.
ALARM ACTION
This defines the behaviour of the alarm when the setpoint is reached.
HYSTERISIS
The hysterisis value is the difference between the points at which the alarm triggers and releases,
expressed in the relevant engineering units.
ALARM DELAY
The alarm will not trigger until the PV has been in the alarm region for more than the specified number
of seconds.
LATCH
When latch is enabled, an alarm will remain triggered until it is manually cleared.
13.1 OUTPUT MENU FUNCTION BLOCKS
13.2 RELAY OUTPUT MENU
ALARM ACTION
ALARM BEHAVIOUR
OFF
(Off)
The alarm is always off
LO
(Low)
The alarm triggers when PV < setpoint, i.e. low alarm
HI
(High)
The alarm triggers when PV > setpoint, i.e. high alarm
dEu
(Deviation) The alarm triggers when PV moves out of a deviation band e.g. if the flow drops below
or above the set point by 10 L/m.
tESt
(Test)
Alarm is on
Not Triggered
Hysteresis
Hysteresis
Setpoint
PV
Alarm Function
Triggered
High Alarm
Low
Alarm
Setpoint
Deviation
Deviation
Deviation
Alarm
Alarm
Function
Not Triggered
Triggered
Hysteresis
Hysteresis
POWER ALARM STATUS
Inurt
SETTING RELAY POSITION (A) RELAY POSITION (B)
OFF
X
X
3 and 5
3 and 2
ON
Not in Alarm
nOnInu
3 and 4
3 and 1
ON
In Alarm
nOnInu
3 and 5
3 and 2
ON
Not in Alarm
InuErt
3 and 5
3 and 2
ON
In Alarm
InuErt
3 and 4
3 and 1
13.3 RE-TRANSMISSION (mA) OUTPUT MENU
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