Alarm Function And Alarm Modes Lists - Extech Instruments 96VFL Series User Manual

11.3 Alarm Function and Alarm Modes Lists

ALARM FUNCTION LIST
Once a function is programmed in the 'A1Fu' and 'A2Fu' parameters (Menu 4, Options), set
the setpoint in Menu 1 ('A1SP' or 'A2SP'). For Alarm ON/OFF Timers, set the timer in Menu
4, Options ('P.TME'). See the separate section on Alarm ON/OFF Timers for details.
'A1FU' / 'A2FU'
setting
Alarm Type Operation
No Alarms No Alarms
Relay trips when the process (PV) exceeds the 'AxSP'
Process
value (Menu 1).
High alarm
Relay trips when the process (PV) falls below the 'AxSP'
Process
value (Menu 1).
Low alarm
The Alarm setpoint equals the Setpoint (SV) plus the
Deviation
'AxSP' (Menu 1) setting. For example, if SV = 400 and
High alarm
A1SP = +10 then the Alarm relay will trip when the
temperature rises above 410
The Alarm setpoint equals the Setpoint (SV) plus the
Deviation
'AxSP' setting. For example, if SV = 400 and A1SP = -10
Low alarm
then the Alarm relay will trip when the temperature falls
below 390
Band High Alarm trips when PV is higher than the setpoint band.
alarm
Band Low Alarm trips when PV is lower than the setpoint band.
alarm
See dedicated ON/OFF Alarm Timer section.
ON-Timer
See dedicated ON/OFF Alarm Timer section.
OFF-Timer
o
(400 – 10 = 390).
VFL Series User Manual v2.0 10/20
28
o
(400 + 10 = 410).