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API to SG Calculator
The American Petroleum Institute established API gravity as a measure of the density of petroleum liquids relative to water. The greater the API, the less dense the liquid. Our float switch product line lists the specific gravity (SG) which the …
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Float Switch Handling and Care
Float Switch Handling & Care   Handle With Care Avoid dropping float. Could effect sensor           Do Not Dip/Submerge Float Cables In Any Fluid May cause insulation issues       Mounting Tip: Vibration may cause …
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Normal Positions of Float Switches
Normal Positions of Float Switches   A glass reed switch is hermetically sealed inside the stem from the liquid environment. “Normal” float position means the fitting and wires are on top and the float is resting at the bottom of …
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Sinking VS Sourcing Digital Outputs
Sinking VS Sourcing Digital Outputs A sinking digital (input/output) provides a grounded connection to the load, whereas a sourcing digital(input/output) provides a voltage source to the load. Figure 1: Sinking digital output is connected to a sourcing digital input. In …
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4-20 mA PLC Calculator
4-20 mA PLC Calculator To connect our float switches to a PLC for 4-20mA output, wire the switch with two resistors as show below. Consult your PLC’s datasheet for input resistance (impedance) on analog input pins*. Type this and your …
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Material Selection and Chemical Resistance Information
Material Selection and Chemical Resistance Information Choosing the correct switch materials can often mean the difference between years of dependable service and equipment failure. Materials that work well in oils or petroleum products may not be the best for common …
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Thread Sealing and Engagement
Thread Sealing and Engagement In order to create a properly sealed environment, care must be taken to properly thread and seal your float switch. Here are a few words of advice to assist you. Always be sure to consider the …
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Pump Level Control
Pump Level Control Controlling your fluid level with a pump or valve can easily be achieved by combining your SMD Fluid Controls product with a Double Pole Double Throw (DPDT) relay. By using two single point float level switches or …
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Magnetic Reed Switch Technology and Protection
Magnetic Reed Switch Technology and Protection Magnetic reed switch technology has been a proven technology for more than 50 years to dependably and safely sense a wide range of liquids and positioning. The internal switches are hermetically sealed and capable …
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Specific Gravity
Specific Gravity Resource Specific Gravity (SG) is the ratio of the object’s density to that of water. Since water has a specific gravity of 1 at sea level, liquids and substances with a specific gravity lower than 1 will float …
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