Instruction Manual

Copyright © 2006 CiDRA Corporation Page 10-10
20675-01 Rev 02
should be discarded and closed loop controls switched to manual
during a critical alarm.
The alarm can be cancelled either manually or will clear automatically
when the alarm condition is no longer present depending on the menu
option selected (see below).
The following table lists the alarm parameters with their default values.
Alarm Parameter Condition User
Entry
Warning
Default Value
Critical
Default Value
TMP> Y > 80 °C > 90 °C
Band Temperature
TMP< Y < 0 °C < 0 °C
SPL> Y > 200 dB > 200 dB RMS Sound Pressure
Level
SPL< Y < 50 dB < 80 dB
Volumetric Flow Quality VFQ< Y < 0.3 < 0.2
Speed Of Sound Quality SSQ< Y < 0.03 < 0.01
Event log updated LOG N
Sensor overload OVL N
FLW> Y > 30 ft/s > 30 ft/s Volumetric Flow or True
Liquid Flow
FLW< Y < 3.2 ft/s < 3 ft/s
GVF> Y > 100 % > 100%
Gas Volume Fraction
GVF< Y < 0% < 0%
Sensor Failure FAIL N
Table 16 Alarm Triggers
Note: The alarm trigger for Flow (VF or TLF) and Gas Volume Fraction
(GVF) can be set from the transmitter menu. All other values must be
set using SONARtrac Basic (or higher level) user program.
Up to three alarm triggers can be selected. For example, an alarm
output may be programmed like this:
Warning = TMP I LOG I VF
(Warning = Band Temperature or Event Log Updated or VF)
Critical = FAIL I OVL & LOG
(Critical = Sensor Fail or Sensor Overload and Event Log Updated
The menu inputs for setting ‘Alarm’ are described in the following
paragraphs.
‘
Alarm Control’ menu is used to activate the ‘Warning’ and ‘Critical’
alarm functions. Once turned ‘
On’ it is used to select the parameters
the alarm will activate on (refer to Table 16).
The ‘
Manual Clear’ function under ‘Alarm Control’ has options of
‘
Disable’ and ‘Enable’. In the ‘Disable’ mode the alarm will
automatically clear when the alarm condition no longer exists. In the
‘
Enable’ mode, the alarm must be reset manually by opening the front
door of the transmitter and pressing the ‘
Exit’ button. Note: For
transmitters installed in Class I Division 2 area follow established
safety procedures prior to opening transmitter door.