Lower Threshold Delay; Setting The Emissivity Ratio (Two-Colour Mode); Emissivity Of Materials (One-Colour Mode) - Siemens 7MC3052-1AB68 Operating Instructions Manual

Two-colour pyrometer, 7mc3052-series

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6.14 Lower threshold delay

The output impulse can be lengthened to make sure the output impulse is correctly

identified, e.g. by a downstream control system.

Lower threshold delay: [d2] → [d2 . d r] = 0...10.0 sec.

The difference between measured temperature and true temperature can be

compensated by changing the emissivity ratio. Make this adjustment for selective

interferences or when the emissivity for wavelength 1 and wavelength 2 will be

different because of the material that is being measured.

• Emissivity ratio [q] → [q. E SP] = 80 - 120 %

The pyrometer has a quick adjustment feature to set the emissivity

ratio. In process value mode, the value can be set directly with the keys

▲or ▼. It is not necessary to access the menu. When simultaneously

pressing the MODE key, the display shows the current measuring tem-

perature while the emissivity coefficient continues to be adjusted in the

background. This is an easy way to determine the emissivity when the

object temperature is known. The changed values are directly adopted.

The pyrometer reacts to the thermal energy (infrared radiation) emitted by an

object. The ability to radiate heat depends on the type of material and its surface

properties. A description of the calculation of emissivity is in Chapter 17/ Page 38.

The ability of a body to emit infrared radiation is expressed by a material constant

called emissivity coefficient or just emissivity. This coefficient lies between 0 and

100 %. A body with ideal radiation (black body) has a coefficient of 100 %. At the

same temperature, bodies with real radiation emit a lower radiation. Therefore, the

emissivity coefficient is < 100%. For this reason, adjust the emissivity coefficient

of the target object on the pyrometer to be able to determine the exact tempera-

ture. With the configured lower emissivity coefficient, the pyrometer automatically

compensates for the lower radiation.

• Emissivity: [S] → [S . E PS] = 10...110%

Operating instructions

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