Revisions: IC660EBA023A , IC660EBA023B , IC660EBA023C , IC660EBA023D , IC660EBA023E , IC660EBA023F , IC660EBA023G , IC660EBA023H , IC660EBA023I , IC660EBA023J , IC660EBA023K , IC660EBA023L , IC660EBA023M , IC660EBA023N , IC660EBA023O , IC660EBA023P , IC660EBA023Q , IC660EBA023R , IC660EBA023S , IC660EBA023T , IC660EBA023U , IC660EBA023V , IC660EBA023W , IC660EBA023X , IC660EBA023Y , IC660EBA023Z ,
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Thermocouple Input Blocks are primarily used to monitor temperature inputs from standard thermocouples. They can also be used to measure low level voltage input signals. Two blocks are available: 115 VAC/125 VDC Thermocouple Block(IC660BBA103) 24/48 VDC Thermocouple Block(IC660BBA023) They are the same except for the power supply. Features A Thermocouple block has six input circuits, in three isolated groups. \\\" 10 V common mode voltage (maximum) allowed between 2 points in a group. Each group has two thermocouple input circuits and two remote cold junction compensation inputs. Group to group isolation is 300 volts. Each input can interface to type J, K, T, E, B, R, S, and N (#14 AWG Nicrosil vs. Nisil) thermocouples. The block provides cold junction compensation for all thermocouple input measurements. Each channel can be configured to use an internal sensor, an external sensor, or a user defined value for cold junction compensation. An external signal from a remote junction can be either a voltage (XJV) or a current (XJI) analog of temperature. The XJV input is scaled for 1.0mV per degree Celsius and the XJI input is scaled for 1.0uA per degree Kelvin. After compensation, the block linearizes each thermocouple input measurement according to the NBS monograph for the type in use. Each input measurement can be adjusted up to \\\" 100.0C or \\\" 100.0F for greatest accuracy. The blocks perform the following diagnostics: Internal fault detection Open Wire detection Overrange and Underrange input indication High and low input alarms An output is provided to drive a Bus Switching Module (version IC660BSM021 only). Compatibility These blocks are compatible with PCIM and QBIM modules. Hand held Monitor IC660HHM501D, version 3.5 (or later) is required. For a Series 90 70 PLC, the CPU must be rel. 2 (IC697CPU731 or 771) or later. The bus controller must be rel. 2 (IC697BEM731) or later. The programming software must be Logicmaster 90 70 rel. 2.02 or later. For a Series Six PLC, the CPU must be rev. 105 or later. For a Series Six Plus PLC, rev. 110 or later is required. The programming software must be Logicmaster 6 rel. 4.02 or later. For a Series Five PLC, the CPU must be rev. 3.0 or later. The Logicmaster 5 programming software must be rel. 2.01 or later. a44491 BSM BSM DC DC XJV XJV TC1 TC1 TC2 TC2 XJI XJI XJV XJV TC3 TC3 TC4 TC4 XJI XJI XJV XJV TC5 TC5 TC6 TC6 XJI XJI Thermocouple Input (24/48 VDC .4A Max) GE Fanuc GENIUS 15 15-2 Genius I/O Discrete and Analog Blocks User s Manual September 1993 GEK-90486D-2 Specifications Block Type: Six thermocouple compatible inputs, three isolated groups of two. Catalog Numbers: 115 VAC/125 VDC Thermocouple Block Terminal Assembly Only Electronics Assembly Only IC660BBA103 IC660TBA103 IC660EBA103 24/48 VDC Thermocouple Block Terminal Assembly Only Electronics Assembly Only IC660BBA023 IC660TBA023 IC660EBA023 Size (Height x width x depth): Weight: LEDs (I/O Block): Heat Dissipation: 8.83 (22.44cm) x 3.50 (8.89cm) x 3.94 (10.00cm) 4 lbs. (1.8 kg) Unit OK, I/O Enabled 9W maximum Block to Block Isolation: Group to Group Isolation: 1500 V for one minute 300 V 115VAC/125 VDC block power: 115 VAC 125 VDC Power supply voltage Power supply dropout time: 93 132 VAC @ 9W 47 63 Hz 1 cycle 105 145 VDC @ 9W 10% max. ripple 10 mS 24/48 VDC block power: Power supply voltage Power supply dropout time 18 56 VDC @ 9W, 10% max. ripple 10mS minimum Input Characteristics: Voltage measurement: Range Resolution Accuracy (at 25C) Bandwidth of input amplifier filter Temperature coefficient 25.0mV to +150mV Less than $ 4 mV Less than $ 10mV error typ, $ 20mV max. 8 Hz $ 2mV/C typical Internal Cold Junction Measurement: Range Offset at 25C Linearity Resolution Temperature coefficient 0 to 60C $ 2 C typ. User adjustable to zero at any temperature. $ 0.15C Less than $ 0.01C $ 0.05 per C External Cold Junction Measurement: Range Scale factors Resolution Accuracy 25.0C to +150.0 C 1.0C per millivolt, 1.0K per microampere Less than $ 0.01 C $ 0.1C Input update time (all channels): 2.0 sec (typ), 3.0 sec (max) Open wire detection response: less than 5.0 seconds Diagnostics: Open Wire, Overrange, Underrange, High Alarm, Low Alarm, Internal Fault Environmental: Operating Temperature Storage Temperature Humidity Vibration: 0C to +60C (+32F to +140F) 40C to +100 C ( 40F to +212F) 5% to 95% (non condensing) 5 10 Hz 0.2 (5.08mm) displacement, 10 200 Hz at 1G 15 GEK-90486D-2 Chapter 15 Thermocouple 6 Input Blocks 15-3 Block Operation A Thermocouple Input Block has three isolated pairs of inputs. Transformers isolate power and optical couplers provide signal isolation. For each pair of inputs: 1. After filtering, each signal input is sequentially switched into a common amplifier whose output is applied to a voltage to frequency converter. The output signal frequency of the VFC is applied to a frequency counter via an optical coupler. The output frequency is counted for a 400 millisecond gate time, which is a common multiple of all the common line frequency periods. This provides considerable rejection of line frequency pickups. 2. The multiplexer intersperses other inputs between the two main thermocouple input times. The other inputs come from the cold junction sensors and from internal references. The cold junction inputs are measured and stored for later compensation of the normal thermocouple input measurement errors. 3. To detect and correct for any gain or offset drift in the amplifier or VFC, the block takes new readings of factory calibrated internal reference levels during operation. These new measurements are compared to reference values stored by the block. 4. The processor converts the cold junction temperature value to a voltage as specified by the NBS monograph for the thermocouple type in use. This voltage is then added to the thermocouple measurement before converting to thermal units. Since there may be some small differences between the cold junction temperature measurement and the actual cold junction temperature, an offset adjustment can be entered using a Hand held Monitor. These offsets are due to variances in the terminal strip assembly and the correction factors are therefore stored in the Terminal Assembly EEPROM. 15 15-4 Genius I/O Discrete and Analog Blocks User s Manual September 1993 GEK-90486D-2 Block Measurement Accuracy The overall accuracy of the block in a given application depends on both: 1. Accurate measurement of the thermocouple millivolt signal. 2. Accurate compensation of the cold junction connections. The block can measure the input millivolt signal to an accuracy of \\\" 10mV (typical) or \\\" 20mV (maximum). Depending on the thermocouple type used and the temperatures being measured, measurement accuracy in C or F can be determined. The output from a thermocouple varies in a non linear manner as the temperature being measured changes. Furthermore, each thermocouple type has a unique characteristic. The following table may be used as a guide to estimate accuracy in units of degrees. It lists optimal accuracy for each thermocouple type, without allowing for conditions that might be encountered in the application, or for the accuracy of the specific thermocouple being used. For a more accurate estimate, consult the NBS monograph published for the thermocouple type used in the application, referencing the temperature range to be measured. Thermocouple Type Average Sensitivity: mV/C Optimal Accuracy in C J 52.6 0.19 K 38.8 0.26 T 40.5 0.25 E 67.9 0.15 B 7.6 1.32 R 12.0 0.84 S 10.6 0.95 N 38.5 0.26 Cold junction compensation can be performed internally by the block itself, or remotely. The block has a cold junction sensor which is set at the factory to compensate the cold junction to within \\\" 2C typically. If a more accurate setting is required, this compensation can be adjusted using a Hand held Monitor, after the block is installed (see page 15-14). 15 GEK-90486D-2 Chapter 15 Thermocouple 6 Input Blocks 15-5 Input Data Format Each bus scan, a Thermocouple block broadcasts 12 bytes of input data. Each input consists of 2 bytes of data in the configured units (C, F, mV, or counts). Appendix B shows reference usage for a Series 90, Series Six, or Series Five PLC. Byte # Description 0 Input channel 1, bits 0 7 1 Input channel 1, bits 8 15 2 Input channel 2, bits 0 7 3 Input channel 2, bits 8 15 4 Input channel 3, bits 0 7 5 Input channel 3, bits 8 15 6 Input channel 4, bits 0 7 7 Input channel 4, bits 8 15 8 Input channel 5, bits 0 7 9 Input channel 5, bits 8 15 10 Input channel 6, bits 0 7 11 Input channel 6, bits 8 15 Hand held Monitor Input Display The Hand held Monitor displays the values in the configured units. The following example shows the Monitor Block screen with configured units of tenths of degrees C. REF 601 624 I I1: 20.2C I2: 50.0C > 15 15-6 Genius I/O Discrete and Analog Blocks User s Manual September 1993 GEK-90486D-2 Diagnostics Circuit diagnostics for Thermocouple Input Blocks are listed below. These diagnostics are automatically performed by the block for any active circuit. Active circuits can be configured not to send diagnostic messages to the CPU if a fault occurs. However, such circuits still respond to faults and report them to the Hand held Monitor. If a circuit is configured as inactive , it will not detect faults or report diagnostics. If the CPU requests diagnostic information from the block using a Read Diagnostic datagram, the block returns current diagnostics for all active circuits, including any with CPU fault reporting disabled. It will not return diagnostics from inactive circuits. Internal Fault An internal fault occurs if one or more of the internal references is faulty. While this fault is present, the block reports a value of zero for each channel using the faulty reference(s). The block s Electronics Assembly should be replaced. Open Wire The block reports an Open Wire diagnostic if there is a missing or faulty connection to the thermocouple input, XJV input, or XJI input for the channel. Overrange/Underrange This diagnostic is reported only if engineering units of Celsius or Fahrenheit are selected. It indicates either that: 1. The input temperature exceeds the expected range for the thermocouple type in use. The expected range for each thermocouple type, derived from the corresponding NBS monograph, is: |
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