Revisions: IC660BBA020A , IC660BBA020B , IC660BBA020C , IC660BBA020D , IC660BBA020E , IC660BBA020F , IC660BBA020G , IC660BBA020H , IC660BBA020I , IC660BBA020J , IC660BBA020K , IC660BBA020L , IC660BBA020M , IC660BBA020N , IC660BBA020O , IC660BBA020P , IC660BBA020Q , IC660BBA020R , IC660BBA020S , IC660BBA020T , IC660BBA020U , IC660BBA020V , IC660BBA020W , IC660BBA020X , IC660BBA020Y , IC660BBA020Z ,
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Voltage/Current 4 Input/2 Output Analog Input/Output Blocks have four independent input circuits and two independent output circuits. Two block versions are available: 115 VAC Analog I/O Block (IC660BBA100) 24/48 VDC Analog I/O Block (IC660BBA020) They are identical except for the power supply. Features Each circuit on a Voltage/Current Analog I/O Block can accept or provide signals in one of five analog ranges: 0 to 10 volts DC, 10 volts DC to +10 volts DC, 5 volts DC to +5 volts DC, 0 to 5 volts DC, or 4 to 20 mA (1 to 5 volts DC). External resistance can be used to interface these blocks to current loop devices with other signal ranges. The block converts the input and output signal levels to/from digital count values and translates them into engineering units values that relate to the application. The block s internal power supply drives current mode output loads up to 300 ohms each. For loads up to 2K ohms, an external 24 or 48 VDC power supply can be used. For current-loop applications, Current-source Analog blocks may be more suitable. See chapters 11 through 13. Individual inputs can be set up to operate in Alarm Input Mode. In this mode, the input s analog value is not sent to the HHM or the CPU. Instead, the block will report values that indicate whether the input signal exceeds either of its alarm levels. Additional configurable features include: Selectable Input Filter Time up to 1024mS Output powerup defaults Output Hold Last State or default CPU Redundancy Block diagnostics are performed automatically: Input Low Alarm and High Alarm detection Open Wire detection Input Underrange or Overrange Output Underrange or Overrange Compatibility These blocks are compatible with all Genius bus controllers, PCIM and QBIM modules. Any Genius Hand held Monitor can be used. For a Series Six PLC, the CPU must be rev. 105 or later. For a Series Six Plus, rev. 110 or later is required. The programming software must be Logicmaster Six rel. 4.02 or later. For a Series Five PLC, the CPU must be rev. 3.0 or later. The Logicmaster Five programming software must be rel. 2.01 or later. GEK 90486D 2 Chapter 10 Voltage/Current 4 Input/2 Output Analog Blocks 10-3 Block Operation The first four circuits on a Voltage/Current Analog I/O block are inputs. One 12 bit analog to digital (A/D) converter is time shared between the input circuits. The block converts each input signal voltage or current to a digital count value. It then scales the count value to an integer that represents the engineering units for that input. Processor Case Ground Shield Filter a40660 IN COM GND JMP A/D AMP Analog to Digital Converter MUX RTN Power Supply Ground NOTE: Common ground and case ground are shared between two output channels Circuits 5 and 6 are outputs. A 12 bit digital to analog (D/A) converter serves the output circuits. The block scales the engineering units output received from the CPU to a digital count value. It then converts the count value to an output signal voltage or current. 20V 1 a40659 Processor V to I Converter COM GND Case Ground 1 S/H VOUT D/A Power Supply Ground Buffer Amplifier Sample Hold Circuitry 12 bits plus sign D/A converter Common ground and case ground terminals are shared between output channels NOTE: Accuracy is within \" 0.5% maximum, \" .2% typical over the entire span of the reading at 25C. This means accuracy is within 50mV on the 10 volt range, 5mV on the 5 volt range, and 100mA on the 4 to 20 mA range. The blocks automatically calibrate all internal 10 10-4 Genius I/O Discrete and Analog Blocks User s Manual September 1993 GEK-90486D-2 Inputs and Outputs Each engineering units input and output is a 16 bit twos complement number. Appendix B shows reference usage for a Series 90, Series Six, or Series Five PLC. Input Data Format A Voltage/Current 4 Input/2 Output Analog block broadcasts 8 bytes of input data each bus scan. 0 Hand held Monitor I/O Display The Hand held Monitor displays each input or output as a whole integer value. The Monitor Block screen shows the current value of two circuits at a time. REF 97 120I I1: 10838 I2: 11637 > 10 GEK 90486D 2 Chapter 10 Voltage/Current 4 Input/2 Output Analog Blocks 10-5 Circuit Scaling The block automatically scales each input or output to/from a value in engineering units. This whole integer number can represent any type or increment of units meaningful to the application. For example, if the current value of a temperature input was 116.37F, it might be reported as: 116 degrees, or 1163 tenths of degrees, or 11637 hundredths of degrees All circuits can be scaled independently, as explained later in this chapter. Example of Scaling an Analog Circuit A circuit is configured in the 0 to 10 volts DC range. It measures a velocity input. Electronic sensors and mechanical linkage external to the block have determined that an input level of +1.5 volts DC is equal to 20 feet/second ( 6 meters/second), and that +9 volts DC is equal to +180 feet/second (+50 meters/second). Plotting these values on a graph shows that a signal of 5 volts DC corresponds to a speed of 73.3 feet/second. 20 9, 180 73.3, 5 20, 1.5 Because engineering units values are whole integers, this would be rounded to +00073. For better resolution, the circuit is reconfigured to units of hundredths of feet/second. New scaling values are configured which are 100 times the original values. The low engineering units value of 20 is reconfigured as 2000. The high engineering units value +180 is changed to +18000. Now, the 5 volt DC signal represents +07333 (hundredths of feet/second). 10 10-6 Genius I/O Discrete and Analog Blocks User s Manual September 1993 GEK-90486D-2 Diagnostics If a fault occurs, the block reports it to the Hand held Monitor and takes appropriate corrective action. Individual circuits can be configured not to send diagnostic messages to the CPU if a fault occurs. If the CPU requests diagnostic information from the block using Read Diagnostics datagrams, the block returns current diagnostics for all circuits, including any with CPU fault reporting disabled. Open Wire Diagnostic The OPEN WIRE diagnostic detects an open wire at an input terminal. The diagnostic is only available for circuits set to operate from 4 to 20 mA. If the circuit current drops below 2 mA, the block sends an OPEN WIRE message. Nothing is done to alter the actual input data. Input Low Alarm and High Alarm Diagnostics Individual low alarm thresholds and high alarm thresholds can be configured for each input. If an input is over its high alarm limit, the block sends a HIGH ALARM message. If an input is under its low Alarm Threshold, the block sends a LOW ALARM message. The alarm message identifies the input circuit which is in alarm. Only one message is sent upon reaching the limit. Since the input value is supplied as part of the normal input status update, the CPU can determine how much over the limit it is. Input Underrange and Overrange Diagnostics The block sends an UNDERRANGE or OVERRANGE message if: A. The input voltage or current is outside the circuit s configured range. Therefore, when the block converts the signal level to digital counts, the result is lower than 4095 or higher than +4095. To prevent this, the input signal should be clamped appropriately. B. The channel scaling is incorrect. When the block converts the digital counts value to engineering units, the result is lower than 32,767 or higher than +32,767. This should be corrected by adjusting channel scaling. Output Underrange and Overrange Diagnostics The block sends an UNDERRANGE or OVERRANGE message if conversion of the engineering units output it receives from the CPU results in a counts value that corresponds to a signal outside the circuit s configured range. For example, if the output is configured for 0 to +5V and the conversion from engineering units to counts results in a value of 2V at the output, the block sends an UNDERRANGE diagnostic. If an underrange or overrange condition occurs, the block clamps the output to the selected range limit to protect external hardware. 10 GEK 90486D 2 Chapter 10 Voltage/Current 4 Input/2 Output Analog Blocks 10-7 Field Wiring Field devices are wired to terminals 5 32, which accept AWG #22 through AWG #14 wires. Do not overtorque the terminal screws. Power Source Wiring For block power, connect the power source to terminals 6 and 7. For a 24/48 VDC block, connect the source to the DC+ terminal and the return to the DC terminal. For a 115 VAC block, connect the source to the H terminal and neutral to N. For the 115 VAC block (IC660BBA100) only, if Class 1 Division 2 conditions must be met for Factory Mutual, install a 250 volt 1/8 amp slow blow fuse in series with the Hot AC power connector: Wiring for I/O Devices The ground (GND) terminal (5) is for block safety. It is connected internally to the block chassis, and to terminals 12, 20, and 28, which are marked GND. Each pair of signals has one ground terminal and one common terminal, for shield termination if desired. The three common terminals are connected together internally to the source. For a voltage input device, connect the device in series between V+ and the terminal marked IN for that input. Connect V to RTN. For a voltage output device, connect the load to the terminals marked VOUT and COM for that output. If current mode (4 20mA) is used for an input circuit without an external resistor, connect a jumper from the terminal marked JMP to the terminal marked RTN for that circuit. If an input current device operates outside the 4 20mA range, connect a resistor across the voltage inputs. For example, to measure 10mA to 50mA current loop signals, install a 100 ohm resistor. |
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