The Interface Solution Experts
11
CPT
PC-Programmable Signal
Isolater/Converter
Alarms
Trip Low and Trip High Alarms
In the Alarm Parameters portion of our CPT
Confi guration Program you may choose a “Trip Low”
and “Trip High” limit. In choosing your limits you are
setting the parameters for your unit to notify you if your
process input drops below (Trip Low) or exceeds (Trip
High) your trip point setting.
Deadband
Deadband (0-100%) is a type of buffer zone. It allows
an alarm to remain tripped even after the process
input has returned to, or passed, the trip point. If
no deadband is set, the alarm will reset itself once
reaching the trip point.
Fail Safe/NON Fail Safe Alarms
A Fail Safe alarm, if in the alarm condition, will remain
in the alarm condition even if power to the unit is
removed.
Fail Safe alarm trip relays are energized whenever the
process input is in a non-alarm condition (including
any deadband setting). These relays de-energize
when the process input trips the alarm.
NON Fail Safe alarm trip relays are energized
whenever the process input is in an alarm condition.
These relays de-energize when the process input
returns to the reset point (including any deadband).
Band Alarm
The Band Alarm incorporates Low and High Trip
points, Deadband and Delay (0-120sec).
The Band Alarm combines two Trip Alarm settings.
The fi rst alarm is always confi gured as Low Trip
(Trip Point Low) and the second as High Trip (Trip
Point High). See Figure 5 for information on alarm
parameters.
The Band Alarm is activated when the Process
Variable is outside of the Low/High Trip point ranges.
The Trip Low is always lower than the Trip High and
their deadbands are inside the range of Low/High
Trip. The span between the Low and High Trip is not
limited, which allows control of measurements in a
very narrow range.
Fault Alarm
To simply be alerted in the case of any fault that may
arise, select the “Fault Alarm” button. This requires no
parameters to be set and will notify you anytime a fault
is sensed.
Note:
Once you have confi gured all parameters,
download to the unit by either selecting “Download
Confi guration” in the Confi guration dropdown menu
located in the Communications bar or by clicking the
button.
Figure 5. Band Alarm Parameter Graph
