Relay Fundamentals

Open an HVAC control panel, and you’re likely to find at least one relay mounted inside. Sometimes you find lots of relays! Even though relay technology has been around since the 1800s, there is still a need for relays in control panels. What components make up a relay? How are relays typically shown in wiring diagrams? What functions can a relay perform? Stay tuned for some answers… What Components Make Up A Relay? A relay is constructed from the following components: Electromagnet (coil of wire with … [Continue reading]

Using a Multimeter Series – Resistance Measuring Basics

“Resistance is futile, Buwhahaha” exclaimed the villain, rubbing his hands together in glee as our hero struggled to free himself from the ropes that bound him. Yep, we’ve all seen those Grade B movies.  Maybe in that situation resistance is futile, but in the world of electronics and HVAC controls resistance (electrical resistance) is very useful! Designing selected values of resistance into the appropriate points of circuits lets us control the voltages and currents so the circuits perform as desired.  The … [Continue reading]

Using a Multimeter Series – Current Measuring Basics

If you are involved in installing or troubleshooting HVAC systems, sooner or later you will be taking electrical current measurements. This tutorial will discuss the basics of how to take those current measurements. Current is measured in units of amperes, usually abbreviated to simply “amps.” When working with small currents (less than 1 amp) it may be more convenient to describe current in “milliamps,” typically abbreviated as “mA.” When you see the term “milliamp” or “mA” this means 1/1000 of an ampere. … [Continue reading]

Using a Multimeter Series – Voltmeter Basics

If you live in the world of HVAC design/installation, sooner or later you’re going to need to take measurements on a circuit using a voltmeter (even if it’s “not your job,” we all know how that goes). So we thought it would be a good idea to put together some basic instructions on using a voltmeter. Even if you’ve been using a voltmeter for years, there might be some tidbit of information here that you hadn’t thought about before. :-) Voltmeter or Multimeter? These days you’d be hard pressed to find a test … [Continue reading]

Kele’s UL Panel Shop: Your Source for Meeting Code

Did you know that when you assemble power supplies, controllers, relays, transmitters, and all that other stuff into an enclosure for your control panel, there’s a rule in the NEC that requires your panel to be listed and labeled as an industrial control panel? Article 409 of the NEC is devoted to the installation of industrial control panels, which are defined as an assembly of two or more components consisting of: Power circuit components only, such as motor controllers, overload relays, fused disconnect … [Continue reading]

Kele Customers Have Spoken and the Water Detector Family Has Grown

Selling a service is selling the intangible. You know, as a consumer, if you are getting great service from a business. You can feel it, but sometimes it’s hard to actually define. Many times, listening to a demand, a complaint, or a request is all that’s needed to provide great service. In product management circles, Voice of the Customer (VoC) is one of the most important drivers in product development. If we LISTEN really well, the solution has already been provided for us. If a customer says, “I wish you had a … [Continue reading]