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Watlow D4T Data Logger
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Chapter 5 Function Reference
Signals
Direction
Label
Type
Function
Receivers
IN Analog Monitored for alarm conditions
CTR Analog Defines the center value relative to which the alarms are
evaluated
SIL Digital
On silences the alarm (see Silencing)
CLR Digital
On clears the alarm if the condition that caused it no longer
exists (See Latching)
OFF Digital
On makes the function act as if Type was set to off
Transmitter
- - - - Digital
Indicates the alarm state (see Logic)
Name
Uniquely identify this FB using up to 20 alphanumeric characters.
Type
To monitor an analog signal for alarm conditions relative to another signal, set Type to
Devia-
tion Alarm
.
Sides
Select whether the receiver (IN) is monitored for high, low or both high and low alarms.
Options:
• Both
: IN is monitored for high, low or both high and low alarms.
• High
: IN is monitored for a high alarm only. The low alarm is not monitored.
• Low
: IN is monitored for a low alarm only. The high alarm is not monitored.
Hysteresis
Set how far the process must return into the normal range before the alarm can be cleared.
Hysteresis defines how far below the point at which a high alarm occurs the signal must drop
before a high alarm can be cleared and how far above the point at which a low alarm occurs
the signal must rise before a low alarm can be cleared.
Range: 1 to 9,999 °F or units
2 to 5,555 °C