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System 471
Function Card

  • SYSTEM 471           Back to System 471
    ADC Resolution:    16-bits, including sign.
    Gain Accuracy:       0.05%.
    Gain Stability:         (0.01% + 0.003%/C).
    Linearity:                (0.02% + LSB).
    Static Crosstalk:    120dB between channels, dc to 1KHz with 350 ohm source; 10 V
                                     maximum non-overloaded input.
    Zero Offset:            10 m V, channel-to-channel.
    Zero Stability:         (5 m V RTI + 1.25 mV RTO) (0.5 m V/ oC RTI + 0.1mV/oC RTO).
    Noise:                      8.5mV RTI, 1.5mV RTO at 10 KHz Throughput
                                     3.7mV RTI, 1.5mV RTO at 1 KHz Throughput
    Noise =                    [(RTI x Gain) + RTO]1/2


    32 Bit TTL Input - 470010           Back to 471
    This card reads 32 bits of input TTL data as two groups of 16 bits each. A Hold output signal handshakes with the device being read. Hold is a 10 mS pulse of selectable polarity asserted when either 16-bit group is to be read. This feature is especially useful when reading digitally-coded levels from a counter, DVM, clock, etc., which, if read in it's transitional state, would result in ambiguous data.
    An Enable input allows the user to decide when to update the cards input register. All inputs and outputs interface with either standard or low power TTL logic. Jumper wires select positive true or negative true logic levels.


    Inputs:               High-Level Input Voltage: 2.0 V min; 5.0 V max
                               Low-Level Input Voltage: 0.0 V min; 0.8 V max
    Input Current:    20 mA max
    Input Current:   -400 mA max
    Enable:               1000 ohm pull-up resistor
    Outputs:             High-Level Output Voltage: 5.25 V max
                                Low-Level Output Voltage: 0.4 V max
    Output Current: 250mA max
    Output Current: 40mA max


    16 - Bit Isolated AC/DC Input - 470011         Back to 471
    This 16-Point card accepts on/off input signals ranging from 12 V to 48 V, ac or dc, providing isolation between channels as well as from ground.


    Input Current:                  21 mA @ 48 V,  8.1 mA @ 24 V,  1.4 mA @ 12 V
    Common Mode Voltage: 1000 V max
    Response Time:               50 mS



    Two-Channel Frequency or Period Input-470012        Back to 471 The Two-Channel Frequency or Period Input card accommodates inputs from tachometers, flowmeters, or other frequency-related devices. Frequency or period measurements or straight event counting are selectable by switches on the card.

    For flexibility, each channel accepts two types of inputs. One set of input terminals, for TTL logic levels, is optically coupled. The other input is intended for use with signal levels that vary with frequency. An event zero-crossing detector accepts inputs from 200 mV to 100 V at frequencies to 100 KHz.

    A crystal-controlled clock provides accurate time bases for measurements on both channels while each channel has its own 32K counter. After each measurement, the counter is reset. Frequency measurement involves counting the number of input pulses occurring between clock pulses.


    Frequency Mode:   0.01% of reading 1 count
    Period Mode:        0.01% of reading input rise time (0.6 to 4V transition)
    Ranges (Max):
                                    Frequency Mode:   327Khz
                                    Period Mode:          32.7 Sec
                                    Count Mode:           32767 counts
    Sink Current:         16 mA max
    Common Mode:     300 V max
    Frequency:             dc to 350 KHz
    Non-isolated Input:
                                    Input Voltage: 200 mV min; 100 V max
                                    Input Impedance: 50k ohms
                                    Frequency: dc to 100 KHz

    32 Bit TTL Input/Output - 470013         Back to 471
    The 32-Point TTL Input/Output card provides a 32-bit TTL level bus for user definition. The bus is divided into four bytes, each of which may be programmed separately as either input or output.


    High Level V in:      3.15Vmin, 5Vmax
    Low Level V in:      -1.5Vmin, - 0.9Vmax
    High Level V out:    2.4V min
    High Level I out:    -2.6mA max
    Low Level V out:     0.5V max
    Low Level I out:      24mA max



    ARINC-429 Controller 470014         Back to 471
    ARINC-429 Controller, 470014, is used to interface the System 470 to the ARINC-429, Mark33 Digital Information Transfer System (DITS) bus. It mounts in a standard System 470 function card slot and provides 4 receiver and 4 transmitter channels for communication with compatible devices.


    * Four receiver channels
    * Four transmitter channels
    * Received data sorted by Label
    * Data packet for interdependent Labels
    * Received data read by 470 scan list
    * SDI support
    * Both fast and slow bit rates supported



    Two-Channel Frequency or Period Input - 470015       Back to 471
    The Two-Channel Frequency or Period Input card accommodates inputs from tachometers, flowmeters, or other frequency-related devices. Operating modes include frequency measurement, period measurement and pulse counting. Selection of mode, clock frequency, number of periods included in the measurement and desired polarity are all programmable.

    For flexibility, each channel accepts two types of inputs. One set of input terminals, for TTL logic levels, is optically coupled. The other input is intended for use with signal levels that vary with frequency. An event zero-crossing detector accepts inputs from 100 mV to 100 V at frequencies to 100 KHz.


    Internal Time Base:       0.01% of nominal
    Frequency Mode:           0.01% of reading 1 count
    Period Mode:                  0.1% of reading to 100mS 0.01% of reading to 1.0mS
    Event Counting Mode:   1 count
    Input Characteristics:
         Isolated TTL Input:
            Input Voltage:        5.25V, maximum
            Sink Current:         16mA, maximum
            Common-mode:      300V, maximum
            Frequency Range:  dc to 350KHz
        Level Detector Input:
            Input Voltage:         100mV, minimum to 100V, maximum
            Frequency Range:  dc to 100KHz



    32-Bit TTL Output--470030         Back to 471
    The 32-Bit TTL Output card provides two 16-bit outputs for driving TTL-compatible loads or other loads not exceeding output capability (30 V maximum; 40 mA maximum). Dual-rank registers permit the simultaneous updating of all outputs.

    All outputs are open-collector gates with pull-up resistors to the internal 5 V supply for driving standard TTL or 5 V CMOS loads. Placement of a jumper permits use of an external voltage source up to 28 V. Outputs can then interface to high voltage CMOS logic or be used to drive relay coils, lamps, or other loads not exceeding 40 mA.

    Output polarity of each group of eight outputs is determined by jumper placement. This allows the user to arrange logic polarity to any desired power-up/reset condition required by the application.


    Open Circuit Voltage:    +30 V max
    Sink Current:                  -40 mA max



    Eight-Point Form 'C' Relay Output--470031         Back to 471
    The Eight-Point Form-C Relay Output card provides eight three-wire form-C outputs (normally open, normally closed, and common) to drive various control devices. Each relay has a "set" and "reset" coil and is magnetically latched in its current state at power down. Eight control bits are used to address and control the relays individually. Dual-rank registers permit simultaneous updating of all relay states.


    Initial Contact Resistance:                30 milliOhm, max
    Maximum Contact Switching Power: 2000 VA, 150 W (resistive)
    Maximum Switching Voltage:            250 VAC
    Maximum Switching Current:            8 Amperes
    Breakdown Voltage:                          1000V between open contacts
                                                                 1000 V between contacts and ground
    Set/Reset Time:                                  8mS (approximately)



    16-Channel Differential Multiplexer Cards      Back to 471
    System 470 offers four types of differential multiplexer cards intended for analog signal inputs in full scale ranges of 5mV to 10.24V.

    Card 470050 is the basic differential multiplexer used for measuring voltages over the entire range; the others offer alternate input configurations. Card 470051 provides open source detection, 470052 is equipped with shunt resistors for measuring 4-20 mA inputs and 470059 has direct input (w/o filter).

    Except for 470059, the cards are equipped with two-pole, passive R-C filters having a terminal rolloff of 12 dB/octave. The -6 dB corner frequency of 10 Hz provides greater than 25 dB attenuation of input noise components at the 60 Hz power line frequency.

    The open source detection feature recognizes open thermocouples, broken wires and high resistance or open input connections. Card 470052 has a 250 Ohm shunt resistors on each channel for sensing 4-20 mA input.

    Specifications: (System 470 with 470050 Cards Installed)

    Number of Channels:         16 guarded differential input channels per card
                                                 Input sources may be grounded or floating.
    Input Impedance:                10 MegOhms: Power on or off.
    Input Filter:                         Passive RC filter on each channel;2-pole,
                                                 low-pass with 12 dB/octave terminal slope;
                                                 -6 dB at 10 Hz and -30 dB at 100 Hz.
    Maximum Input Voltage:    30 V differential or common mode
    Common Mode Rejection: 120 dB (80 dB plus gain in dB to
                                                 120 dB max); dc to 60 Hz with 350
                                                 ohm source imbalance.
    Common Mode Voltage:     10 V operating.
    ADC Resolution:                16-bits, including sign.
    Gain Accuracy:                    0.05%.
    Gain Stability:                      (0.01% + 0.003%/C).
    Linearity:                             (0.02% + LSB).
    Static Crosstalk:                 120 dB between channels, dc to 1 KHz with
    350 ohm source;                  10 V maximum non-overloaded input.
    Zero Offset:                          10 m V, channel-to-channel.
    Zero Stability:                       (5 m V RTI + 1.25 mV RTO)
                                                   (0.5 m V/ oC RTI + 0.1 mV/oC RTO).
    Noise:                                   8.5mV RTI, 1.5mV RTO at 10 KHz Throughput
                                                  3.7mV RTI, 1.5mV RTO at 1 KHz Throughput
                                                  Noise = [(RTI x Gain) + RTO]1/2



    4 Channel Conditioner/Multiplexer - 470054           Back to 471
    For bridge measurements using one, two, or four active arms, this card provides a precision excitation supply, balance control, and terminals for bridge completion, balance limit, and calibration resistors on each channel. Bridge completion resistor kits are available, see below.

    The card includes multiplexer switches and a standard two-pole RC filter, providing the same performance specifications as the 470050 16-Channel Multiplexer. One step shunt resistor calibration is programmable. Up to eight input leads plus shield can be used, giving the user the option of local or remote sensing. 

    Specifications: - Excitation Supply

    Voltage:                     Selectable; 5 V or 10 V.
    Current:                     100 mA max/channel; short circuit
                                        protected. 3.2 Amperes per control
                                        or expansion assembly.
    Line Regulation:        Less than 0.01% or 200mV, whichever is
                                        greater, for 10% line voltage variation.
    Load Regulation:       Less than 0.01% or 200 m V, whichever is
                                        greater, for a no load to full load change.
    Stability:                     0.01% at constant temperature; 0.005%/oC.
    Noise:                         Less than 200m V pk-pk in 10KHz bandwidth.
    Bridge Completion:   Terminals provided for four completion resistors.
    Test Points:                Front mounted jacks for Points: monitoring
                                        excitation and output voltages.
    Bridge Completion
    Resistor Kits:             350 or 120 ohm kits include three bridge
                                         completion and one balance limit resistors.



    Four Channel RTD Conditioner/Multiplexer - 470055  Back to 471
    The Four Channel RTD Conditioning/Multiplexer provides direct connection of 2, 3, and 4-wire, 100 ohm RTDs in a balanced bridge configuration. The card can be configured by jumper placement to accommodate current-excited 4-wire RTDs of values to 1k ohm.

    The card includes multiplexer switches, 10 Hz filter, and excitation source adjustment for each channel. Excitation current is 0.5 mA in the bridge configuration, or 1 mA in the constant current configuration, resulting in very low self-heating errors in the RTDs.

    Specifications: - Excitation Supply

    Current:                       1.0 mA adjustable +/- 1%
    Compliance Voltage:   0 to 3.5 Volts
    Line Regulation:          Less than 0.01% or 0.1mA,
                                          for a 10% line voltage variation.
    Response:                    Output settles to within 1% of setting in
                                          less than 50 microseconds with a no-load
                                          to full-load change.
    Stability:                       0.01% at constant temperature; 0.005%/oC.
    Output Impedance:      1 megOhm minimum
    Ripple:                          Less than 0.2mA peak-to-peak over
                                          the bandwidth dc to 1KHz.
    Test Points:                  Front mounted jacks for monitoring
                                          excitation and output voltages.


    16 Channel Transformer Coupled Multiplexer - 470056
    Back to 471
    The Transformer-Coupled Differential Multiplexer provides 16 channels of analog input for System 470. Each channel is galvanically isolated from other channels and from ground. Common mode voltages of up to 1000 V are rejected.

    Each channel features fully-guarded differential input allowing operation from either grounded or floating input sources. Two-pole, low pass filters approach 12 dB/octave terminal rolloff on each channel.

    Specifications: (System 470 with 470056 Card Installed)

    Number of Channels:            16 guarded differential input channels
                                                   Input sources may be floating or grounded.
    Input Filter:                           Passive RC filter on each channel; two-pole,
                                                   low-pass with terminal slope approaching
                                                   12 dB/octave; -6 dB at 10 Hz and -30 dB at 100 Hz.
    Input Impedance:                  5 megohms, minimum; power on or off.
    Isolation:                               Less than 100 pF from any input terminal to
                                                   ground. CMOS input switches are off with
                                                   system power removed.
    Maximum Input Voltage:     30 V differential, without damage.
    Common Mode Voltage:      1000 V dc or peak ac.
    Common Mode Rejection:   100 dB + gain in dB to 120 dB max; dc to 60 Hz
                                                   with up to 350 ohms source imbalance.
    Full Scale Accuracy:             0.05% of full scale at constant temperature, 0.003%/oC.
    Linearity:                               Less than 0.05% of full scale deviation from
                                                   best fit straight line through zero and full scale.
    Zero Stability:                       (5 m V RTI + 1.25 mV RTO) at constant temperature;
                                                    (0.5 m V/oC RTI 0.1 mV/oC RTO).
    Zero Offset:                            10 m V channel-to-channel.
    Noise (3 Sigma):                    10 m V peak RTI + 1.5 mV RTO.
    Resolution:                             16-bit resolution; 0.003% FS.
    Static Crosstalk:                    120 dB between any two channels; dc to 1 KHz.
    Dynamic Crosstalk:               110 dB to next channel in scan including overload
                                                    (up to 30 V input) and full scale range changing.
    Sample Rate:                         20 samples/second/channel max to meet all
                &nbs bsp;                                  specifications, with u p to 350 ohm source resistance.
    Note: System 470 sample rate must be set to 10 KHz


    4 Channel Isolation Preamplifier/Multiplexer - 470058 Back to 471
    Isolation Amplifier, 470058, is a four channel analog input signal function card providing highly accurate measurements of signals ranging from 5mV full-scale to 300V full-scale. Each channel is galvanically isolated from ground and from the other channels by means of a transformer coupled multiplexer and isolated power supplies. Plug-on mode cards configure each channel for operation with a particular type of transducer. Mode cards provide excitation, calibration switching and bridge completion.

    A common calibration bus is routed to all system channels to allow voltage substitution calibration using an external voltage standard. Mode cards provide additional transducer-specific calibration.

    Separate input and output low-pass filter sections provide 4Hz cutoff frequencies and 24dB/octave terminal rolloff. Input filtering protects the amplifier from noise components which might cause overload or slew-rate limiting. It also reduces the effects of common-mode to normal-mode voltage conversion. The output section further reduces the bandwidth as well as amplifier generated noise.


    Iso-Amp Mode Cards           Back to 471
    Voltage Mode Card, 470362, configures a channel for voltage inputs. It includes switching for voltage substitution calibration and holes for mounting an input attenuator or shunt resistor for current loop operation. RTD Mode Card, 470361, configures a channel for RTD operation. Bridge Mode Card, 470360, configures a channel for operation with bridge type transducers

    Specifications:  Isolation Amplifier with Mode Cards Installed

    Number of channels:              4 true differential input channels
                                                    per card. sources may be grounded
                                                    or floating.
    Input Configuration:              Floating, galvanically isolated.
    Input Impedance:                   100 megohms at dc. Input may be
                                                    grounded or floating.
    Input Filter:                            2 filter sections, each with 2- pole
                                                    passive RC filters on each channel:
                                                    24 dB/octave terminal slope; -3 dB
                                                    at 4Hz.
    Maximum Input Voltage:
    Differential:                            65V dc or peak ac without damage.
    Common-mode:                      300 V dc or peak ac without damage.
    Common-mode Rejection:    160dB, dc to 60 Hz.
    Channel Sample Rate:          200 samples per second maximum
                                                    to meet all specifications.
    System Sample Rate:            10KHz aggregate system sample rate.
    Gain Steps:                            Isoamp provides four programmable
                                                    gain steps of x1, x8, x64, and x512.
                                                    Postamplifier provides gain steps of
                                                    x1, x2 and gains of x1, x2 and x4.
    Full-Scale Ranges:                 5mV to 10.24V in 12 steps using
                                                    PGA gain steps of x1, x2, and x4.
    Offset Error:                           (35 m V at 23C + 0.5m V/C, RTI)
                                                    or (2.0 mV at 23C + 0.1mV/C, RTO)
                                                    whichever is greater, uncalibrated.
    Gain (Slope) Error:                 (0.1% FS at 23C + 0.002% FS/C), uncalibrated.
    Source Current:                      (1.0 nA at 23C + 0.1 nA/C)
    Noise:                                      (0.5 m V RTI + 1.0 mV RTO)
    Crosstalk:                               Less than 0.006% FS between channels.
    Stability:                                  (0.02% FS + 2.0 m V RTI) for 120 hours
                                                    at constant temperature. Includes effects
                                                    of gain stability, offset stability,
                                                    non-linearity and crosstalk.
    Resolution:                             16 bits. (15bits plus sign)



    Two Channel 16-Bit DAC 470070           Back to 471
    The Two Channel DAC Output card provides two channels of analog output from System 470. Each channel consists of a 16-bit digital-to-analog converter (DAC) scaled to deliver 10.24 V output. Each output can deliver 20 mA of load current with remote sense leads provided to cancel line drops. Dual-rank registers permit simultaneous updating of both channels.


    Output Voltage:  10.24 V full scale.
    Output Current:  20 mA.
    Accuracy:            0.02% of full scale. 
    Stability:              0.005% of FS at constant temperature;
                                 0.001%/oC over 0 to 50oC.
    Resolution:          0.00305% FS/count (1 part in 32,768).  
    Noise:                  Less than 500 m V in 10 KHz bandwidth


    Sixteen Channel 12-Bit DAC 470071           Back to 471
    The 16 Channel DAC Output card provides 16 channels of analog output from System 470. Each channel consists of a 12-bit digital-to-analog converter (DAC) scaled to deliver 10.24 V output. Each output can deliver 20 mA of load current with remote sense leads provided to cancel line drops.


    Output Voltage:   10.24 V full scale.
    Output Current:   20 mA. Accuracy: 0.02% of full scale.
    Stability:              0.005% of FS at constant temperature;
                                 0.001%/oC over 0 to 50oC. 
    Resolution:          0.05% FS/count (1 part in 2,048). 
    Noise:                  Less than 500 m V in 10 KHz bandwidth.



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