Installation manual

Series C Controller Configuration and Operation Manual
9-6  Athena Controls, Inc. 900M050U00
9.2.5 Specifying the Alarm Value (Setpoint)
How the alarm setpoint value is used depends on the type of alarm.
• process alarm – activated when process value reaches the value specified
with the alarm setpoint parameter
• deviation alarm – activated when process value differs from the process
setpoint by the value specified with the alarm setpoint parameter
• inverse band alarm – activated when the PV is inside a band centered
around the setpoint; the width of the band above and below the setpoint is
specified with the alarm setpoint parameter
• normal band alarm – activated when the PV is outside a band centered
around the setpoint; the width of the band above and below the setpoint is
specified with the alarm setpoint parameter
Parameter Name:
Alarm 1 Setpoint and Alarm 2 Setpoint (See Note 2 below)
Name as Displayed
:
A1.SP A1.SP and A2.SPA2.SP
Used By:
all except 1ZC
When Displayed:
if alarm action is not event
Range:
RTD and thermocouple input types: sensor low limit to sensor
high limit
linear input types: limited by the scaling defined for the input
using the SCL.LSCL.L and SCL.HSCL.H parameters in the InPInP (input) menu
(See Note 1 below.)
Default:
process alarm: 77
deviation, inverse band, normal band: 1728
Description:
Used to specify the alarm setpoint (process alarm), the alarm
limit (deviation alarm), or the width of the alarm band (inverse
and normal band alarms)
Note 1: The range is reduced when a linear input is used and the value of the dSPLdSPL
(display) menu dEC.PdEC.P (decimal position) parameter is not 0 (zero). See 4.3.2 for more
information about the effect of a linear input on numerical ranges.
Note 2: The Athena Plus protocol code numbers used for these parameters depends on
the alarm operation as shown in the table.
If alarm operation is: Alarm 1 setpoint code is: Alarm 2 setpoint code is:
process alarm C6 D2
deviation alarm C7 D3
inverse band C7 D3
normal band C7 D3