ABUS Technologies A1500 Universal Process Indicator - Manual (Page 8)

ABUS TECHNOLOGIES INC.
8
A1500
6.3 Alarm
6.3.1 Alarm Functions
The alarms can be set to operate in seven different functions. These functions are shown in
table 2 and described below. The alarm can also be set as disabled.
Sensor break – Ierr
The alarm is triggered whenever the sensor breaks or is badly connected.
Low alarm – Lo
The alarm relay is triggered whenever the measured value is below the alarm set point.
High alarm - Ki
The alarm relay is triggered whenever the measured value is above the alarm set point.
Differential low – Dif.lo
Deviation alarm: Alarm relay is triggered whenever the difference (deviation) between the value
measured and the reference value (AlrEF) is beyond values defined in SP.AL. For this function, the
triggering point is defined as:
(ALrEF – SP.AL)
Differential high – Dif.ki
Deviation alarm: Alarm relay is triggered when the difference (deviation) between the
value measured and the reference value (AlrEF) is beyond values defined in SPAL. For this
function, the triggering point is defined as:
(ALrEF + SP.AL)
Differential (or Band) out of range – Dif.ov
Deviation alarm: Alarm relay is triggered when the difference (deviation) between the
measured value and the reference value (AlrEF) is higher than the value defined in SPAL. For
this function, the triggering points are defined as:
(ALrEF – SP.AL) and (ALrEF + SP.AL)
Differential (or Band) within range – Dif.In
Deviation alarm: Alarm relay is triggered when the difference (deviation) between the
measured value and the reference value (AlrEF) is lower than the value defined in SPAL. For
this function, the triggering points are defined as:
(ALrEF – SP.AL) and (ALrEF + SP.AL)
6.3.2 Alarm Timer
The alarms can be configured in the alarm timer. The user can set delays in the alarm action,
define just one pulse for an alarm event, or make the alarm work in the form of sequential pulses.
Table 3 shows these advanced functions. Times T1 and T2 can be programmed from 0 to 6500
seconds (refer to item 8.2). Set 0 (zero) at the T1 and T2 to prompt for a normal non-timer alarm
operation. The LED lights will flash whenever there is an alarm condition regardless of the current alarm
status which may be temporarily off because of the timer action.
6.3.3 Alarm Initial Blocking
The initial blocking option inhibits the alarm from being recognized if an alarm condition is
present when the controller is first energized. The alarm will be triggered only after the occurrence of a