Eurotherm's INSTANT ACCURACY Technology is a new design which is described as US Patent # 5,484,206. This technique is also refered to as INSTANT ACCURACY™, a trademark of Eurotherm. This technology can now be licensed to be used in other applications areas which do not compete with Eurotherm or any Eurotherm product.
INSTANT ACCURACY can be used to improve any temperature sensing (at a distance) where it is not possible to locate the sensor precisely at the point of interest, where thermal impedances are stable but actual heat flow is not. With this technology, sensors may be enhanced and/or simplified:
- On insulated thermocouples the 'stem effect' can be eliminated completely resulting in neglible error and a much reduced response time.
- A sensor which mounts outside of a vessel wall and yet indicates the inside temperature with no 'stem effect'.
- Acquire the temperature through the wall of a container which cannot be perfectly lagged or is even being heated though the wall itself from the outside.
This technology provides a way of accurately acquiring the temperature of a point of interest which is not easily accessible. Previous solutions to the problem focused on minimizing thermal impedance, or minimizing the heat flow, and then accepting the residual error which is sometimes accounted for by a fixed offset adjustment. This invention accepts there will be a temperature difference due to variable heat flow, measures the heat flow and corrects for it thus eliminating the error under all conditions. Sensor manufacturers may be especially interested in a particular form of the invention which is a composite sensor whose electrical behavior is that of a single phantom sensor at the extrapolated position. The dimensions, and therefore the intrinsic time constant, of the composite sensor are smaller than that of the support structure. Composite sensor arrangements are relevant to thermocouple, RTD and semiconductor sensors. The technology is used in Eurotherm's latest generation of temperature controllers (Series 2000™) for eliminating the warmup time and error associated with Cold Junction Temperature sensing for thermocouple inputs. We are now interested in licensing out for use in non competing business areas such as sensors.