PCE roughness tester / roughness meter PCE-RT 1200

The roughness meter is used to determine the surface roughness. The compact roughness meter is a handheld measuring device for mobile use. Due to the power supply via a powerful battery, it can be used directly on site. The roughness meter is used in the laboratory, in production and generally wherever the roughness of surfaces is to be determined. The measured values are displayed on the clear and very concise OLED display directly on the measuring device.

In addition, the roughness meter has a memory option for up to 20 measured values, which can be read out later via the micro USB interface. The measuring software, which is included in the scope of delivery like a USB cable, can also be used for this purpose. The internal battery is also charged via the micro-USB interface. The aforementioned measurement software is particularly suitable when series of measurements are pending. The data is then transferred to the software accordingly and can be evaluated directly on the screen. The roughness meter has a protective cap for the sensor, which protects it from external influences and can be easily screwed onto the device. A calibration plate with roughness standard is also part of the standard equipment and serves to check the correctness of the measurement results.

In roughness measurement, different technologies and surface roughness measuring devices are used to determine roughness. Roughly speaking, a distinction is made between contact and non-contact methods. Within these two distinctions, different approaches to determining surface roughness parameters are used in practice. For example, a tactile surface roughness measuring device can be operated with a single-skid probe system, a double-skid probe system or also with a reference plane probe system. The PCE-RT1200 roughness tester uses the contact stylus method according to ISO 3274. This is a tactile method in which the stylus tip (diamond) of the roughness tester is drawn horizontally over the surface of a workpiece at a uniform speed. The horizontal displacement of the probe tip simultaneously leads to a vertical deflection of the same. This displacement is detected by an inductive displacement measurement in the roughness meter and corresponds to the surface profile of the workpiece.

The surface roughness measuring device thus senses the surface profile, detects deviations in the shape and calculates roughness parameters and profiles from this. It follows that an important parameter in the determination of roughness parameters is the probe tip itself. Depending on the selected tip angle and probe tip radius of the diamond, the roughness meter can map the surface profile more or less accurately. If the angle and radius are large, the diamond tip will only detect the coarser pits, scores and grooves; the more acute the angle and the smaller the radius, the deeper the diamond can penetrate into the profile irregularities and produce an exact image of the surface profile. Here, however, it is also important to weigh things up when selecting a suitable measuring device. A roughness gauge with a pointed diamond and a small radius is significantly more susceptible to wear and brittle fracture than a roughness gauge with a blunter geometry.

For regular use in surface inspection, the roughness meter from PCE Instruments, with a tip angle of 90° and a tip radius of 5 µm, represents a very good compromise between robust, low-wear durability and precise roughness parameter determination according to accuracy class 2. Calibration according to DIN ISO 5436 is therefore possible for the surface roughness measuring instrument without any problems. Rz = averaged roughness depth The averaged roughness depth Rz is the arithmetic mean of the greatest individual roughness depths of several adjacent individual measuring sections. Ra = arithmetic mean roughness Ra is the generally accepted and internationally applied roughness parameter. It is the arithmetic mean of the absolute values of the profile deviations within the reference section. The measured numerical value Ra is always smaller than the Rz value determined on the same roughness profile.