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System 472
Function Card
Specs


System 472           Back to System 472
System 472 offers two types of Differential Multiplexer cards, one with a programmable gain preamplifier on each channel, the other with only a multiplexer to select one of sixteen channels.

32 Bit TTL Input - 472010           Back to 472
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.

Specifications:

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
High-Level
Input Current:    20 mA max
Low-Level
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
High-Level
Output Current: 250mA max
Low-Level
Output Current: 40mA max

 

 

16 - Bit Isolated AC/DC Input - 472011         Back to 472
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.

Specifications:

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-472012         Back to 472
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.




Specifications:

Accuracy:
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 - 472013         Back to 472
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.


Specifications:

Inputs:
High Level V in:      3.15Vmin, 5Vmax
Low Level V in:      -1.5Vmin, - 0.9Vmax
Outputs:
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

Two-Channel Frequency or Period Input - 472015       Back to 472
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.

Specifications:

Accuracy:
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--472030         Back to 472
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.

Specifications:

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

Eight-Point Form 'C' Relay Output--472031         Back to 472
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.

Specifications

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 472
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

 

16-Channel Programmable Preamp/Multiplexer           Back to 472
The 472060 is a high accuracy, low bandwidth card capable of accepting full scale signal inputs ranging from 5mV to 10.24V in 12 programmable gain steps. Accuracies to 3V are achievable on the 5mV range. It is equipped with a 3-pole 10Hz passive filter.

The 470059 16-Channel Differential Multiplexer Card accepts full scale analog signals in the range of 2.56V, 5.12V and 10.24V with no filtering.

Specifications: (System 472 with 472060 Installed)

Number of channels:          16 true differential input channels per
                                             card, expandable to 2048 in 8 assemblies.
Input Configuration:           Balanced, differential. Input sources may
                                             be grounded or floating.
Input Impedance:               10 megohms at dc.
Input Filter:                         Passive RC filter on each channel; 3-pole,
                                             low-pass with 18 dB/octave terminal slope;
                                             -3 dB at 10 Hz. 
Maximum Input Voltage:   30V Differential or common
                                              mode. Power on or off.
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.
Ranges:                                5mV to 10.24V in 12 binary steps; fully
                                              programmable for each channel.
Full Scale Accuracy:            (0.02% FS + 2 uV) for 120 hours at
                                              calibration temperature 5C. Includes
                                              errors contributed by gain instability,
                                              offset instability and non-linearity.
Resolution:                           16-Bit, including sign (0.003% FS) 
Noise:                                   1.5V RTI or 1.5mV RTO

Specifications: (System 472 with 470059 installed)

Number of Channels:          16 true differential input channels per
                                              card, expandable to 2048 in 8 assemblies.
Input Configuration:            Balanced, differential. Input sources may
                                              be grounded or floating.
Input Impedance:                10 megohms at dc.
Input Filter:                          470059 has no filter
Maximum Input Voltage:    30 V differential or common mode.
Common Mode Rejection:  80 dB dc to 60 Hz with 350 ohm
                                              source imbalance.
Ranges:                          2.56V, 5.12V and 10.24V fully
                                              programmable for each channel
ADC Resolution:                 16-bits, including sign. 
Accuracy After Cal.:            0.05% at constant temperature;
                                     0.003%/ C after postamplifier calibration.
Dynamic Crosstalk:             74 dB worst case on adjacent channel in scan.
Zero Stability and Noise:     1.25mV RTO, 0.1mV/C.

 

Two Channel 16-Bit DAC 472070          Back to 472
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.

Specifications:

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 472071           Back to 472
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.

Specifications:

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.

16-Channel Isothermal - 472081          Back to 472
The Isothermal Connector provides the means of terminating thermocouple input cables at the rear panel of the System 470. It can be used with any of the following analog input cards.
470050 16 Channel Multiplexer 
470051 16 Channel Multiplexer with Open Source Detection
470056 16 Channel Transformer- Coupled Multiplexer
472060 16 Channel Amplifier/Mux

The Isothermal Connector plugs directly into the input (edge) connector of the analog input card. Thermocouple cables are brought into 15 sets of screw terminals on the connector, corresponding to multiplexer input channels 1 through 15. A temperature transducer in the connector supplies a reference voltage to channel 0 that is proportional to the termination temperature.

The termination temperature and the type of thermocouple on each channel is the information the CPU requires to convert the thermocouple voltage to temperature. Since the conversion is under control of the CPU, thermocouple types can be mixed.

Specifications:

Reference Temperature:                 1 mV/oC (Channel 00) referenced at 0oC
Reference Temperature Accuracy: 0.25oC over the range of 10o to 45oC.
Thermocouple Inputs:                      Channels 01 through 15.
Temperature Gradient:                    0.1oC across terminations

 

 


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