IntelliPack Series 841T Transmitter/Alarm User's Manual Frequency Input
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Limit Alarm - Deadband (Frequency Inputs Only):
Deadband is associated with the setpoint and is
programmable over the entire input range (this is also
field adjustable). Deadband determines the amount the
input signal has to return into the “normal” operating
range before the relay contacts will transfer out of the
“alarm” state. Deadband is normally used to eliminate
false trips or alarm “chatter” caused by fluctuations in the
input near the alarm point. Note that deadband may also
apply to latched alarms. If the alarm is latching, it is
recommended that the deadband be set to a minimum.
Deadband has no application to the event counter input.
IMPORTANT:
Noise and/or jitter on the input signal
has the effect of reducing (narrowing) the
instrument’s deadband and may produce contact
chatter. Another long term effect of contact chatter
is a reduction in the life of the mechanical relay
contacts. To reduce this undesired effect, increase
the deadband setting.
Alarm Indicator:
A yellow LED (labeled “RLY”) for the relay
provides visual status indication of when the relay is in
alarm (LED is ON in alarm). This LED is also used in
field configuration mode to indicate whether setpoint or
deadband is being adjusted.
Relay - Time Delay :
Programmable from 0 milliseconds to
25.5 seconds in 100ms increments for this model
(typically used to help filter input transients and avoid
nuisance alarming). A minimum delay of 100ms is
recommended for increased noise immunity and
conformance to applicable safety standards. This delay
does not apply to control of the transmitter’s analog
output.
Relay - Operating Mode (Failsafe/Non-Failsafe):
User
configurable for “failsafe” operation (relay deenergized in
alarm state), or non-failsafe operation (relay energized in
alarm state). Failsafe mode provides the same contact
closure for alarm states as for power loss, while non-
failsafe mode uses alarm contact closure opposite to
power loss conditions. Upon power up, relay may cycle
states during diagnostic operation.
Relay - Reset (Automatic/Latching):
The relay may be
configured to automatically reset when the input retreats
past its setpoint and deadband, or the relay may latch
into its alarm state. A push-button reset switch is located
on the front of the module (use the up or down arrow
buttons) and is used to exit the latched state (this may
also be accomplished under software control).
Other IntelliPack Configuration Software Capabilities
In addition to configuring all features of the module described
above, the IntelliPack Configuration Software includes additional
capabilities for testing and control of the module as follows:
•
Monitors the input and output signal values and allows
polling to be turned on or off.
•
Allows a configuration to be uploaded or downloaded to/from
the module. Also provides a means to rewrite a module’s
firmware if the microcontroller is replaced or a module’s
functionality is updated.
•
Provides controls to separately calibrate the input and output
stages and restore the original factory input or output
calibration in case of error.
•
Provides controls to reset a module and reset a latched
alarm.
•
Provides a control to reset the event/pulse counter to zero.
•
Provides a control to adjust a transmitter’s output signal
independent of the input signal.
•
Allows optional user documentation to be written to the
module. Documentation fields are provided for tag number,
comment, configured by, location, and identification
information. This information can also be uploaded from the
module and printed.
•
Allows a module’s configuration to be printed on an easy to
read two page form, including user documentation.
For complete information on the IntelliPack Configuration
Software, refer to Transmitter Configuration Manual 8500-570.
Notes: