Using VLT AQUA Drive in submersible pump application The system consists of a submersible pump controlled by a Danfoss VLT AQUA Drive and a pressure transmitter.The transmitter gives a 4-20 mA feedback signal to the VLT AQUA Drive, which keeps a constant pressure by controlling the speed of the pump. To design a drive for a submersible pump application, there are a few important issues to take into consideration.TopTherefore the drive used must be chosen according to motor current. 1The motor is a so called “Can motor” with a stainless steel can between the rotor and stator. There is a larger and a more magnetic resistant air-gap than on a norma l motor hence a weaker field which results in the motors being designed with a higher rated current than a norm motor with similar rated power.2The pump contains thrust bearings which will be damaged when running below minimum speed which normally will be 30 Hz.
Ceramic (Porcelain and Glass) Insulators
Fantastic porcelain insulators collection (41st Annual Mid Ohio Insulator Show )Materials Porcelain is the most frequently used material for insulators. Insulators are made of wet, processed porcelain. The fundamental materials used are a mixture of feldspar (35%), china clay (28%), flint (25%), ball clay (10%), and talc (2%).The ingredients are mixed with water. The resulting mixture has the consistency of putty or paste and is pressed into a mold to form a shell of the desired shape.The alternative method is formation by extrusion bars that are machined into the desired shape. The shells are dried and dipped into a glaze material.
Definition: Waste [Maintenance Tip]
Any activity that consumes resources and produces no added value to the product or service a customer receives. There are seven types of manufacturing waste: 1. Production over immediate demand2. Excess work in progress and finished goods inventories3. Scrap, repairs and rejects4.
Monitor for Normal Air Consumption [Maintenance Tip]
This is an easy implementation of condition monitoring that can save you tons of money and labor. Install an air consumption meter with an analog output in a work cell or on a particular machine and connect the output to a programmable logic controller (PLC). Monitor for normal air consumption. Set an alarm level just above normal consumption and send the output to a human machine interface (HMI) when the normal consumption is exceeded. The….
Learn the Secrets of Your Equipment [Maintenance Tip]
From the RCM2 world, how many protective devices do you have? Of those, how many are you maintaining? Examples of protective devices are a High High Level Switch in an acid tank or an Emergency Stop on a Conveyor. The failure of protective devices is typically not evident to the Operator under normal operating conditions. Therefore, the failure of the protective device is a hidden failure. Consider the acid tank as an example. When the….
