PTL Hermann GmbH is a specialist in the field of level measurement technology - Level switches

PTL Hermann GmbH is a specialist in the field of level measurement technology, specialising in the development and production of vibrating limit switches. The devices of this company are designed to detect liquid levels in all kinds of vessels and silos. All products are developed and manufactured in-house and sold through distributors worldwide, who have decades of experience in level measurement technology and ensure the highest quality solutions for their customers.

The company's products are manufactured on the basis of its own innovative and patented technology, known as "Einstabtechnik". All development and production activities are carried out in Germany, ensuring the high quality and reliability of the products. In addition, their production process follows the high quality standards of DIN EN ISO 9001:2015 and all products are CE certified. To ensure the safety of their products in specific environments, they are also certified for dust and gas explosion protection under ATEX Directive 2014/34/EU.

Liquid Open Light
PTL Hermann GmbH develops and manufactures vibratory level switches for detecting the presence of powdered or granular solids stored in various silos, hoppers and containers.Principle of operation: the vibration system is forced to vibrate at its resonance frequency by means of a piezoelectric crystal actuator. If fill material (bulk solids) covers the vibrating blade of the probe, its vibration is damped, which is sensed by the electronic circuitry and the output switch; when the blade is exposed due to a drop in level, the instrument restarts vibration and the output switches back.

Product Features
High sensitivity: can detect bulk materials with a minimum density of 20g/litre
Suitable for large bulk materials: up to 40mm particle size
Robust design: patented reinforced diaphragm withstands high vertical and lateral forces
No false switching: The vibration system of the LevelSwitch is designed so that only one rod is in contact with the medium to be inspected, thus avoiding bridging, which is a typical cause of false switching in sgn.Schwinggabeln.
No false switching due to deposits or cavity formation on the vibrating rods: the unique diamond-shaped cross-section allows bulk material to flow out easily.
High-quality materials: the probes are entirely made of stainless steel and the evaluation electronics are housed in a die-cast aluminium enclosure (IP66 / 67).
ATEX certification: the product is also ATEX certified for use in explosion hazardous areas caused by combustible dusts or gases.

Technical data
Installation length: approx. 170 mm
Mounting position: any
Handling connection: Thread 1-1/2" EN10226 (DIN2999) or NPT
Power supply: Wide range electronics 20-250V AC/DC with 2-pole relay output; 24V-DC with transistor output; NPN or PNP depending on wiring; 20...30V-DC with transistor output; 20...30V-DC with transistor output. . 30V-DC with 8/16mA current output; power supply and evaluation, e.g. via separate evaluation unit CV2000AE
Approvals: Explosion-proof for dust: ATEX II 1/2D for zones 20/21
Gas explosion protection: ATEX II 1G Ex ia IIB T4 for zone 0
Power supply and evaluation is carried out by means of the corresponding operating device CV2000AE [Exi].