Control panel is electrical control for Decanter Centrifuge. Different decanter centrifuge has different kinds of control panel. Flame Ex-proof small control panel is used for fixed speed centrifuge; A bigger PLC positive pressurized control panel is used for variable frequency drive centrifuge. GN can offer different type of decanter centrifuge as below:
High standard & variable speed centrifuge: GNLW363BG-VFD
High standard & Fixed speed centrifuge: GNLW363BG
Economic standard & variable speed centrifuge: GNLW363BD-VFD
Economic standard & Fixed speed centrifuge: GNLW363BD
PLC VFD control panel VS conventional VFD control panel for Variable Speed Centrifuge
Dimension: PLC VFD control panel: 800x500x1200mm; conventional VFD control panel: 800x500x2000mm; The former one is more compact and easy for transportation.
Operation: conventional VFD control panel is manually operation with some buttons. The PLC control panel is touch screen operation, with more detailed information.
Positive EX-proof cabinet for variable speed centrifuge
Equipment is pressurized to a positive pressure relative to the surrounding atmosphere with air or an inert gas, thus the surrounding ignitable atmosphere cannot come in contact with energized parts of the apparatus. The overpressure is monitored, maintained and controlled.
Strictly according to IEC standard, Flameproof (EX d) cannot be used for VFD panel. As the transducer will continually generator heat during working, flameproof is sealed and isolated with environment, it is not good at cooling. It is not stable under higher temperature, the heat cannot cool down fast, so the panel may keep incessant stop.
China use the same EX standard as IEC. But most Chinese company still make flameproof for VFD panel. For our company GN Solids Control, we only use flameproof for fixed speed panel.
Flameproof Ex-proof cabinet for fixed speed centrifuge
Equipment construction is such that it can withstand an internal explosion and provide relief of the external pressure via flamegap(s) such as the labyrinth created by threaded fittings or machined flanges. The escaping (hot) gases must sufficiently cool down along the escape path that by the time they reach the outside of the enclosure not to be a source of ignition of the outside, potentially ignitable surroundings. Equipment has flameproof gaps (max 0.006″ (150 um) propane/ethylene, 0.004″ (100 um) acetylene/hydrogen)
Advantages of positive pressured control panel
The inside pressure of the panel is higher than outside environment. In this case, the possible explosion gas cannot enter into the panel.
The VFD panel we give you is made by German company Bartec. During that time, a customer order centrifuges with Atex certificate, it is North America standard, Chinese company cannot do, so we order panels from German company Bartec. And also use the same design panel for you for save time. It is customized design deferent with our common design, so our machinery engineer not familiar with it.
Pressurized panel with air-condition (AC) is a bit bigger in size, but it can cool the panel more easy and for a large temperature scope than vortex tube.