IntelliPack Series 841T Transmitter/Alarm User's Manual Frequency Input
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The module uses a comparator and logic gate to convert an
input signal into a digital TTL pulse stream. A microcontroller
samples the pulse stream and measures its frequency or counts
the number of pulses. An external counter reset terminal is also
included. The module completes the user specified input to
output transfer equation and controls an optically isolated Digital-
to-Analog Converter (DAC) to produce a corresponding process
current or voltage output signal. The microcontroller also drives a
separate alarm circuit to control the relay contacts.
Flexible transmitter functionality and an optional limit alarm
combined in a single device, plus convenient reprogrammability,
makes this instrument extremely powerful and useful over a
broad range of applications. Input averaging may be used with
frequency inputs to smooth input frequency jitter. Debounce may
be used with pulse counting inputs to eliminate counting false
pulses due to electromechanical relay contact bounce and other
mechanical effects. The analog output may produce a normal
(ascending), or reverse (descending) response.
The relay of 841T-1500 models may be configured as a limit
alarm with deadband, with latching or non-latching contacts, and
for failsafe or non-failsafe modes. A programmed relay time
delay may be implemented to filter transients and minimize
nuisance alarms.
All IntelliPack modules are designed to withstand harsh
industrial environments. They feature RFI, EMI, ESD, EFT, and
surge protection, plus low temperature drift, wide ambient
temperature operation, and isolation between input, power,
output, and relay contacts. They also have low radiated
emissions per Conformity European (CE) requirements. As a
wide-range DC-powered device, the unit may be powered from
DC power networks incorporating battery back-up. Additionally,
the input power terminal is diode-coupled, providing reverse
polarity protection. This allows the unit to be connected to
redundant power supplies, or several units to safely share a
single DC supply.
Units are DIN-rail mounted and removable terminal blocks
facilitate ease of installation and replacement, without having to
remove wiring. Transmitter power, output, and relay wiring are
inserted at one side of the unit, while input wiring is inserted at
the other side. Connectors are an industry standard screw clamp
type and accept a wide range of wire sizes.
The safe, compact, rugged, reconfigurable, and reliable
design of this transmitter makes it an ideal choice for control
room and field applications. Custom IntelliPack module
configurations are also possible (please consult the factory).
Key IntelliPack 841T Features
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Agency Approvals
- cULus Listed.
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Easy Windows
Configuration
- Fully configurable via our
user friendly Windows 95
or NT
Configuration Program.
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Nonvolatile Reprogrammable Memory
- Module uses an
advanced technology microcontroller with integrated, non-
volatile, downloadable flash memory. This allows the
functionality of this device to be reprogrammed many times.
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Convenient Field Reprogrammability
- Adjustment to
transmitter zero and full scale, plus alarm setpoint and
deadband can be made via module push-
buttons and LED’s,
thus facilitating in-field changes without having to connect a
host computer (frequency inputs only).
Key IntelliPack 841T Features
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Fully Isolated
- The input, power, and output circuits, and
optional relay contacts are all isolated from each other for
safety and increased noise immunity.
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Wideband Frequency Input
- This model accepts
frequency inputs from 0Hz to 50KHz. Inputs below 1Hz are
represented as 0Hz.
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Flexible Pulse Counter Function
- The built-in event
counter function counts pulses on the positive or negative
edge, upward, in the range 0-65535, and includes an
external counter reset. The counter may wrap around from
65535, latch at a programmed count value, or automatically
reset itself to 0 after reaching a programmed count value.
The counter may also be reset remotely via the PC or via a
counter reset control signal wired to the unit.
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Input Filtering
- Inputs include hysteresis. Other filtering
modes include averaging (frequency inputs), debounce
(event counter), relay time delay (alarms), and deadband
(alarms). This helps to reduce the negative effects of
measurement jitter, false counts, electro-mechanical relay
contact bounce, plus other mechanical effects.
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Universal Analog Outputs
- Supports current output
ranges of 0-20mA, 4-20mA, & 0-1mA, and 0-5V or 0-10V
outputs. Current outputs will drive up to 550
, typical.
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Flexible Interface Supports Many Input Types
- The
programmable pull-up/down resistors & selectable excitation
provides support for a variety of input types including TTL,
dry contact, low or high side transistor switches, magnetic
pickups, proximity sensors, and open drain or collector
switches.
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Supports Bipolar or Unipolar Input Signals
- Interfaces
with both zero crossing and non-zero crossing signals.
Voltage threshold and relative hysteresis are user
selectable.
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Convenient Input Excitation
- Input in8.2V & +12V
excitation supplies for powering sensors & transducers (up
to 24mA).
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Normal Or Reverse Acting Output
- The output of this
transmitter may be software configured for a normal acting
(ascending), or reverse acting (descending) response.
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Self-Diagnostics
- Built-in routines operate upon power-up
for reliable service, easy maintenance, and troubleshooting.
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Wide-Range DC-Powered
- This device receives power
over a wide DC supply range and the power terminal is
diode-coupled. This makes the product useful for systems
with redundant supplies and/or battery back-up.
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Wide Ambient Operation
- The unit is designed for reliable
operation over a wide ambient temperature range.
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Hardened For Harsh Environments
- The unit will operate
reliably in harsh industrial environments and includes
protection from RFI, EMI, ESD, EFT, and surges, plus low
radiated emissions per CE requirements.
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Convenient Mounting, Removal, & Replacement
- The
DIN-rail mount and plug-in type terminal blocks make
module removal and replacement easy.
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High-Resolution Precise D/A Conversion
- Transmitter
output is driven with a high-resolution, low noise, Sigma-
Delta, Digital-to-Analog Converter (
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DAC) for high
accuracy and reliability.
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LED Indicators
- Used to indicate operating, alarm, system
diagnostic, and field configuration status.