P-An
Alarm Hysteresis:
The Alarm Hysteresis is that area on
one side of the alarm setpoint where the output does not
change condition. That area or deadband is intended to
eliminate relay chatter at alarm setpoint with less wear
on the relay. With a wide Alarm Hysteresis, the controller
takes a longer time to change output condition. With a
narrow Alarm Hysteresis, the controller takes a shorter
time to change output condition. Enter a value which is
just large enough to eliminate relay chatter.
Setting Range: 0 to 50% of full scale, set in E.U.
P-dP
Decimal Point Position (Resolution):
The Decimal Point
Position is the resolution at which the controller displays
the process variable and other parameter values. The
controller can indicate one, one tenths or one hundredth
of a unit. The Decimal Point Position does not increase
the accuracy of the controller, it only increases the reso-
lution. For a thermocouple, one degree resolutions are
usually sufficient due to the accuracy rating and the pro-
grammed input range. For a RTD (Pt100), one degree or
tenths of a degree may be entered, because of the
increased accuracy of these sensors, depending on the
programmed input range. For a 1-5/0-5V DC or 4-20/0-
20mA DC signal, integers, tenths or hundredths of a unit
may be entered depending on the programmed input
range.
Low Alarm
Setpoint
Low Alarm
Hysteresis
Main
Setpoint
High Alarm
Hysteresis
High Alarm
Setpoint
Alarm ON
Alarm ON
Alarm OFF
Alarm OFF
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