• Filter Selection Guide Sheet - 184KB PDF
• Single Phase Filters - 3MB PDF
• Power Entry Modules - 2.5MB PDF
• Three-Phase Filters - 823KB PDF
• DC Filters - 1.25MB PDF
• Technical Considerations - 926KB PDF

Radio frequency interference (RFI) is unwanted noise generated by a wide variety of electronic and electrical devices. Governments of most industrial countries, including the United States, Canada and many European nations, have enacted guidelines on emitted RFI. Most notable are FCC docket 20780 in the United States and VDE (Verband Deutscher Electrotechniker) 0871 and 0875 in Germany. Computing devices, industrial controls, medial instrumentation, electronic games, and other electronic devices that generate unwanted radio frequency energy greater than 10 kHz must comply with these governmental and safety agency requirements.

The product design concepts, controlled assembly and testing processes at Curtis Industries ensure the highest quality RFI power line filters to help systems manufacturers meet governmental emissions and safety requirements. Computer-controlled production test equipment assures Curtis Industries customers that all electrical parameters are met on each filter shipped.

Terminal Blocks and Relay Sockets - Curtis Industries electronic terminal blocks and relay sockets are manufactured to exceed all required specifications. Curtis Industries terminal blocks reach industry defining upper and lower limits in Center to Center spacing as well as the industry upper and lower ranges for wire (AWG).

The only limit to the number of terminals available in Curtis Industries electrical terminal blocks is your job specification. Curtis Industry terminal blocks are available as surface mount, PC mount, panel mount and feed through styles with a wide variety of top and bottom terminals available.

Curtis terminal block voltages and current (Amps) vary to suit applications. Curtis Industries terminal block are all CSA certified and meet underwriters Laboratories standards for recognition. Housings of Phenolic, polyphenylene and thermoplastic-polyester are stable to extreme temperatures exceeding industry standards.

See Curtis Industries 9000 Series Terminal Blocks Catalog.

Curtis Industries relay sockets utilize the follow features and many more, view the entire catalog for complete details.

Permanent-numbered terminals for easy identification - Thermoplastic sockets with closed-back design which eliminates panel insulation, and resist breakage - Nickel-plated screw-type terminals on break-resistant barrier-type terminal block for fast, easy connection. - Screw-type terminals on other models with captivated wire clamps to eliminate lugging - Compact, printed circuit design - Glass epoxy G-10 printed circuit boards - Relay sockets can be spaced out in track for convenient insertion of marking strips, for relay identification - High-quality sockets for maximum relay retention and electrical conductivity.

Liquid Level Controls - Operating on the principle of conductivity (the ability of a liquid to conduct electricity), Curtis Industries Liquid Level controls sense and control the level of almost any fluid or moist solid. These units are available with fixed or adjustable setpoints to control levels in fluids having an external circuit resistance up to 3,000,000 ohms.

In operation, two or more submerged liquid level probes pass a minute electrical current through the liquid to be controlled. This current, typically 500 microamperes, is introduced to a solid-state resistance-sending amplifier which provides sufficient gate signal to trigger a silicon-controlled rectifier (SCR). The firing threshold is accurate to within 2% of operating differential and is adjustable by means of a potentiometer. The output of the SCR is used to operate the plug-in control relay. When anticipated loads exceed that of the standard relay, an auxiliary contactor is utilized.

Control Models ELS, LCS/LHS, LCF and RSA are designed for forward mode operation. They interpret a decrease of external circuit resistance from setpoint as an “ON” signal. Model LCR is designed for reverse mode operation. It energizes when external circuit resistance increases above setpoint. Model DLC is intended primarily for pump and heater level/lockout applications. See the appropriate catalog sections for specific application information.

When selecting a liquid level control, several factors must be taken into consideration. Questions arise as to what mode of operation is required, what is the resistivity range of the fluid to be controlled, is a fixed or variable setpoint called for, are special functions required such as a pump or heater lockout, etc. Use the connection diagrams in the Curtis Industries Liquid Levels Control Catalog to select the ideal control for your specific application.

European Style Terminal Blocks -