Multi-Level Sensors

Quality, Reliability, Simplicity of Operation… Direct Level Magnetic Sensors Custom Built To your Exact Specifications

When you must provide a complete cycle, or function to a process, rather than a simple contact, a multi-level sensor is your simplest and most cost effective solution. Essentially it is a probe with multiple magnetic sensors housed inside, with switch logic and dimensions to suit a specific job, such as automatically refilling a day-tank with fuel. Many such jobs can be critical, and it is easy to add redundant levels for control backup, or independent alarm contacts. A low-level alarm for a day-tank with power totally isolated from the control contacts would be a good example. Before you begin, you should gather information on temperature, pressure, and the liquid’s characteristics. Is it still or turbulent? What is the viscosity? Is particulate present? You also need to know what the “load” for the sensor will be. Is there an existing fitting that can be used, or does one need to be installed?

How to specify the perfect multi-level sensor for your system

1. From the Mounting Type charts on the next page, select a PIN ID code letter (i.e. G).
2. From the chart below select an appropriate Sensor Material (i.e. 2 for SS)
3. From the chart below select a Stem Diameter allowed for the fitting and float size of your tank (i.e. 2 for Standard 1/2″ Size).
4. Decide the Number of Levels needed (i.e. 6).
5. Float selection comes next. (In our example, since we have selected Standard Size, we pick from the choices in the Standard Float Series.) Floats come “packaged” with reeds: types SPST, SPDT, 10-100VA; Normally Open or Normally Closed contacts. (i.e. A2-8 means a 15W reed Normally Closed, 8″ down from mount. CAUTION: Floats are designed to fit through female fittings of a stated size, not pipe of that size! (i.e. 2″ SS floats will fit through a 2″ NPT half-coupling, but not through a 2″ NPT Pipe Nipple.) Also, if a sensor is to be mounted up-side down on the bottom of a tank, be sure to reverse the PIN’s float identifying series to obtain the desired electrical condition in the dry state.
6. For Length Overall, refer to the Limitations Chart below, which indicates minimum and maximum dimension limits for a sensor.
7. Wiring Identifiers: From the chart below pick the letter representing the wiring you prefer. However, a very complex sensor may only be available with “common” wiring.
8. Float Retainers: Specify “grip-ring” retainers for lightweight or miniature floats or static, nonturbulent applications. They provide good service in fuel or lubricant use. Collar type retainers should be specified for stainless floats; turbulence in tanks, portable or transportable applications and water based fluids.
9. Strain Reliefs: Mechanical for standard duty. Epoxy potted for tamper resistance, and some protection against light condensation or moisture. Cord Grips in conjunction with cable provide liquid-tight capability from outside as well as inside the tank (immersible).
10. Junction Boxes: Nema 4X provides protection from dirt, dust, bodily contact and water-tightness as in washdown situations. Nema 7-9 are for hazardous areas as defined by electrical codes. Both may contain terminal strips standard, and can be ordered with small control relays.

Sensor Dimensional Limitations

Specification Codes for your Custom Pin (Product Identification Number)

Mounting Types

Float Types – Standard Series

Float Types – Miniature Series