Model AA14-4F010 Four Channel High Isoltation Thermocouple Conditioner
is a high-isolation, four-channel conditioner, accepting real-world temperature signals from Types E, J, K, N, R, S, and T Thermocouples. Based on NIST polynomials, linear output is produced over each thermocouple’s stated operating range, and within the rated accuracy limits—without the need for additional output processing. PLEASE NOTE: WHILE ALL FOUR CHANNELS OF A GIVEN AA14-4F010 CARD MUST BE DEDICATED TO THE SAME TC TYPE, INDIVIDUAL CARDS DEDICATED TO DIFFERENT TC TYPES MAY BE MIXED AS DESIRED WITHIN THE TOTAL DATA ACQUISITION SYSTEM. IT IS ALSO REQUIRED THAT THE AA14-4F010’S CHANNEL NO. 1 BE USED.
This conditioner features true galvanic isolation with pulse-width modulation, allowing sensor-to-chassis or sensor-to-sensor common-mode voltages as high as 1500 V (rms) to be accommodated. Internal reference-junction compensation is automatically selected by thermocouple choice. No external cold junction is required (although the user may supply his own Controlled Ambient Temperature Zone for reference- junction purposes, if desired). A conventional Daytronic four-channel isothermal connector assembly (No. 60323 is supplied with each Model AA14-4F010, with screw terminals for direct connection of TC leads (which cannot be soldered), and with a precision thermistor for measurement of the reference junction temperature. The same connector may be used with any TC type. In the event of a broken thermocouple wire or other “open TC” condition, the AA14- 4F010 will automatically report an indeterminate off-scale reading for the TC channel in question, with positive or negative polarity selectable on a per-channel basis.
Each AA14-4F010 input channel employs an active low-pass filter with a fixed cutoff frequency of 10 Hz. A nominal ±5-V ANALOG OUTPUT is produced by each active AA14-4F010 input channel, for purposes of real-time signal monitoring. Each of these “Auxiliary Outputs” is available on a corresponding mainframe wire-wrap pin. Each output may be individually set, if desired, to represent the prefiltered value of the corresponding input. “Absolute” calibration lets you quickly set up each TC-based data channel simply by entering appropriate “type” and “range” information. During operation, appropriate reference-junction compensation, real-time digital linearization, and engineering-unit scaling are automatically applied for each type of thermocouple used. A second, two-point “zero and span” calibration technique is provided, however, for applications where it is desirable to force multiple TC readings to the same exactly known temperature.