Hi ALL, I need to control the temperature of a furnace. The Thermocouple ouputs are available as RS-485. What Hardware and system configuration should I prefer?

[Gurdas Singh]

I need to automate the control of a gas carburising furnace. The available signals are Thermocouple K-Type (4 nos., one each from the three zones and one from the geometrical center of the furnace) and Oxygen Analyser. That makes it a total of 5 signals, all available in RS-485 format, which I need to acquire (10 samples/second) and then initiate a control action as per the rule base. Reliability is a major issue and the system has to work in harsh conditions.
What hardware would suit my purpose? I would prefer NI hardware which can be programmed via VB or VC++. LabVIEW may be considered as the last option.

Apart from using the thermocouple/Oxygen analyser signals for controlling it is also desired to store them on a PC for analyses and visualisation (via graphs etc etc)
My need is URGENT and would appreciate any help. Thanx in advance
Gurdas

[harry 265]

There are several suppliers of RS-485 interface cards most of which have drivers for Win32 OSs you could use with VB/VC++. Implementing the code should not present any problems.In addition to what NI might have we have had success using dual port and quad port RS-422 interface cards made by Measurement Computing and ICS Advent. These products also support 485.