Product(s) : DAS-TC, DAS-TC/B
Question : What are my upgrade options for the ISA bus DAS-TC/B board?
Keithley offers a number of solutions for measurement of temperature from thermocouple sensors or low level voltage signals.
Still in the plug-in board type of solution, any of the KPCI boards that offer high gain capabilities can also measure temperature from thermocouples. One distinction will be that these more general purpose board products will not perform the voltage to temperature conversions. This would have to be done in the controlling software with an add-in module such as the T/C Library. Another important distinction is that these general purpose board products will not offer channel isolation.
Another cost effective solution that maintains channel isolation and exceeds the scanning speed of DAS-TC/B would be one of the Integra Series mainframes and switch card.
While reading rates of Instrument based products are typically slower than plug-in board products, the integrating A/D converters of instruments gives a much greater immunity to noise than plug-in board products. This greater noise immunity eliminates the need for signal averaging which is a common technique required when using plug-in board based systems. The effective sampling rates, especially for temperature monitoring applications, are quite comparable when considering that each single measurement from an instrument will be usable data.
The Model 2700 offers both GPIB and RS-232 interfaces standard. The 2701 offers both TCP/IP and RS-232 standard. Both of these mainframes can host up to two switching modules. The 7700, 7706, 7708 or 7710 switching modules all offer automatic CJC. The 2700 with one 7700 gives 20 measurement channels at competitive prices to the 16 channel DAS-TC/B. The Integra Series based solution will also perform the voltage to temperature conversion and transmit the measurements in the requested units.
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