Mettler-toledo Ag

Mettler-toledo International Trading (shanghai) Co., Ltd.

Mettler-toledo Instruments (shanghai) Co. Ltd

Fengjin Wang

Changlin Wang

Jürgen Ammann

Xiaokai Wang

Min Xu

Hong Iris Zhu

Cong Wang

Jun Xia

An optical structure has a cavity () with an opening provided at one end and a first through hole or first gap () provided at the end opposite the opening. The cavity is further provided internally with a beam splitter or a dichroic mirror (). A first LED () emits light into the cavity through the first through hole or the first gap, which passes directly passing through the beam splitter or dichroic mirror and exits from the opening of the cavity A second LED () emits light into the cavity through a second through hole or second gap () in a side of the cavity, which is reflected by the beam splitter or dichroic mirror. It is then fused with the light emitted by the first LED. The light emitted by the respective LEDs have an identical optical path length to the beam splitter or the dichroic mirror.

Optical structure

Exemplary embodiments of the present invention are directed to methods and devices for detecting open-circuit and short-circuit failure in an electromagnetic (inductive) measurement of the conductivity of liquids and on the sensor and cable wiring. An electromagnetic measurement of the conductivity of a liquid is performed by immersing a sensor into the liquid, wherein the sensor includes at least 2 toroidal cores, one of them carrying an excitation coil and the other carrying an induction coil. When an AC excitation voltage is applied to the excitation coil, an induced current or voltage can be measured in the induction coil which is proportional to the conductivity of the measured liquid.

Method and device for detecting failures in inductive conductivity measurements of a fluid medium

Exemplary embodiments of the present invention include methods and devices for the electromagnetic (inductive) measurement of the conductivity of liquids by immersing a sensor into the liquid, wherein the sensor includes at least 2 toroidal cores, one of said cores carrying an excitation coil and the other core carrying an induction coil. Exemplary methods include converting the induced current at the induction coil into an alternating square-wave voltage, followed by rectification. A sample-hold circuit may be employed to avoid the transition time of the alternating square-wave current conversion. The demodulated DC voltage is proportional to the conductivity of the measured liquid.

Method and device for inductive conductivity measurements of a fluid medium

Exemplary embodiments of the invention include an input circuit for electromagnetic (inductive) measurements of the conductivity of liquids. The input circuit and the induction coil are directly coupled, and the arrangement includes a current-voltage converting circuit which accomplishes the transformation from current to voltage in the induction coil, and ensures the terminal voltage to be zero. Also there is an anti-saturation circuit which is composed of an integrating circuit and a voltage dividing circuit and serves to prevent saturation in the operational amplifier which is used for the current-voltage transformation. The circuit further includes features for the detection of an open-circuit failure of the sensor coil or cable.

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Shanghai, China

Fengjin Wang