Technical Background

Microwave is an electromagnetic wave with a frequency range of 300MHz to 300GHz, in the late 1960s, it was rapidly developed as a new type of heat source. Microwave is widely used in medical treatment, chemical research, food processing, material heat treatment and other industries due to its rapid and even heating of objects. However, due to the existence of strong electromagnetic field, temperature measurement is still a technical problem in microwave field .Under strong electromagnetic field, when using the conventional temperature sensor (e.g., thermocouple, heat resistance, etc.) to perform temperature measurement, metal made temperature measuring probe and wire will produce induced current under high frequency electromagnetic field, due to skin effect and eddy current effect, theirs’ temperature will be increased, which causes serious interference to temperature measurement, and errors on indicating values or failing on stable temperature measurement. It also brings great harm to microwave equipment.

Fiber optic temperature measurement was developed in 1970s, a new temperature measuring technology, compared with the traditional temperature sensor, fiber optic temperature sensor has some unique advantages, such as resistance to electromagnetic interference, high pressure resistance, corrosion resistance, stable and reliable, high precision, explosion-proof, flame-proof, small size, light weight, etc., which provides an effective way for microwave field temperature measurement. Fiber optic temperature sensing technology is mature now, has achieved large-scale industrial production and application, the cost falls rapidly, it has obvious advantages in the microwave environment temperature measurement, can be expected that the technology will be rapidly promoted in the industrial microwave temperature measurement application in a short time.

Product Description

Name	Performance	Picture
One channel temperature measuring system	Reading temperature Range: -30 - 300℃ Resolution:0.1℃ Temperature accuracy: ±1℃ Sensing cable length:< 10m    Sensing cable diameter:2.3mm Input power: DC 24V Communication port：485 /RS-232Modbus (protocol / RdLight Logger software) Analog output:4-20mA or 0-5V Power consumption:1W
Six channels temperature measuring system	Reading temperature range: -30 - 300℃ Resolution:0.1℃ Temperature accuracy: ±1℃ Sensing cable length:< 10m    Sensing cable diameter:0.45mm Input power: 220V Communication port：485/RS-232Modbus (protocol / RdLight Logger software) Analog output:4-20mA or 0-5V Power consumption:1W

Application Case

Herch company’s fluorescence fiber temperature sensor has been widely used in microwave wood drying, microwave food processing, microwave tea water-removing, microwave digestion and coal desulfurization and other industrial microwave fields, and has received much favorable comments from the users.