Month: January 2021

January 25, 2021

CPI 12v Switches For Demanding Applications

One of the most common applications for CPI switches is when they are configured as in 12v systems as safety switches, interlock switches or manually activated as when they are mounted on steering wheels of work trucks, fork lifts, even motorcycles and mountain bikes.

12v switches are commonly called for in many industrial vehicle designs for everything from horns and alarms, to outrigger proximity detectors in fire engines and backhoe-loaders. The 12V bus is standard for most power supplies and all CPI switches are rated from 5v to 28v so 12v dc operation is perfectly in our sweet spot. Furthermore these switches are fully industrial IP68 rated.

CPI Waterproof Switches are among the most durable 12v switches you will find in the world. They are truly waterproof unlike many marine switches which are simply splashproof.  Our switches are fully sealed and fully submersible, sealed in either Santoprene or Neoprene, including where the leads attach. These options also allow for extended temperature ranges including cold operation down to -40F without contact sticking.

Vehicle Applications for CPI 12V Waterproof Switches

Designers select our 12V switches because their applications are usually outdoor or because they anticipate a harsh duty operational environment. Our 12V switches are rated for over 50,000 cycles (depending on amperage being switched), and are all but impervious to extreme vibration or extended operating temperatures. Here’s a few examples of our most popular 12v Switch variations.

CPI Waterproof On/Off Switches

K1005 shown with optional E1057 bracket for surface mounting.

A great example of our 12v waterproof switch line includes this K1005 rocker switch. This is a maintained contact, on/off type switch, typically available with a neoprene cover. The switch has positive tactile actuation and is available in 2 wire and two conductor cable.

This 12v switch, and all CPI 12v Switches, can be placed in a variety of mounting brackets. These brackets can allow for fixed mounting on a dashboard, pipe mounting, or flexible mounting using a hook mount for flexible operator positioning.

Custom mounting options are available from the factory.

CPI Waterproof 12v Rocker Switches

Pipe mount Pendant Switch

A great example of our 12v Rocker Switch in action is our K1007 SPST Maintained Rocker Switch. With our standard Neoprene seal this switch operates from -60F to 180F without issue and can be specified with current capability up to 15A or electromechanical endurance up to 5 million cycles.  And don’t forget that like all our waterproof switches, the K100X series of Waterproof rocker switches is truly waterproof:  not splash-proof or water resistant.

Pictured here, is our pipe mounting option.


CPI 12v Switches – Waterproof Durability

When designers don’t want to take a chance on field failures, or switch failure in critical safety applications, they often end up at CPI’s doorstep.

Call our engineering team today to discuss your application.

Originally posted: https://www.cpi-nj.com/blog/cpi-12v-switches-for-demanding-applications/

January 11, 2021

CPI Plugstat Thermal Switches – Getting There Slowly

For engineers looking to solve demanding temperature switching applications, robust, standalone thermal switches are surprisingly hard to come by. A quick google search yields hundreds of parts in a confused presentation of thermals, with every shape and size represented, sold everywhere from Alibaba to Amazon. But for the endurance focused designer, there might as well be 0 results.

Sometimes Slow is Good…

In the world of thermal switches, bimetallic switches generally belong to one of two categories:

  1. Snap Action Switches – As the name implies this group of switches has a quick make/break switching action, ideal when there is a fairly large differential between the opening and closing temperatures of activation.
  2. Slow make/break or “Creep Action” devices – These are excellent in temperature control or high limit control applications. They are designed for a narrow temperature differential between opening and closing temperatures where slower cycling characteristics provide some immunity from chattering in precision thermal sensing. This is the CPI Plugstat thermal switch line.

Accurate, and Durable Standalone Thermal Detection and Switching

The primary difference between CPI’s Plugstat Thermal Switches and others is their high endurance design. The PlugStat Series of close tolerance, bimetal thermal switches serve as a robust and accurate temperature control switch at temperature ratings from 17C (0F) to 343C (650F).  This slow make and break thermal switch, open-on-rise device is hermetically sealed, with 1/2-20UNF-3A  thread mounting or other custom mountings available.

Electrically, our switch handles up to 2A at 28V off the shelf, but custom values are possible. No matter what variation you get, the quality of this thermal is in keeping with the quality of the parts that make it.

  • Stainless Steel type 304
  • Stainless Steel type 321
  • Inconel Alloy 600
  • Stycast type 2651
  • Platinum Contacts

Hey, it was Good Enough for NASA…

Despite NASA’s stringent material and electrical requirements for the International Space Station, CPI’s off-the-shelf Plugstat model M1102 met their need for a reliable, space deployable, thermal safety switch solution. In this application, CPI’s switch was used to sense the temperature of a highly specialized liquid to prevent it from turning into a toxic gas during heating. Additionally CPI provided all applicable CoC’s, Material Test Reports, and Chemical Analysis’ required to meet NASA’s stringent quality control. The application is fascinating and can be read about here.

CPI Plugstat switches have been used on tanks and planes both military and commercial for oil overtempt, and hydraulic fluid temperature sensing where designers wanted a reliable, long lasting, standalone thermal sensor in places not so easy to service.  These kinds of applications are really made for the CPI M-series Plugstat switches.

Also available in hermetically glass sealed version.

Contact CPI Thermal engineers today to discuss your application or visit https://cpi-nj.com

Originally posted: https://www.cpi-nj.com/blog/cpi-plugstat-thermal-switches-getting-there-slowly/