Control Panel U blog

Summary: Circuit breakers are sized according to rules established by codes and standards. For common applications, a 250% x motor FLA maximum size limitation is used.  However, this is different when drives are used, or when special circuit protection types are used. Introduction Circuit breakers are commonly used in circuit protection of motor circuits.  Size it wrong and you could end up with nuisance tripping, or even worse insufficient circuit protection. Sizing a circuit breaker for a motor load isn't overly complicated but there are some rules to follow, and a few things to check.  This article simplifies how circuit breakers are sized for motor loads in the US. What can go wrong? Do you ever wonder why a breaker isn't sized to match the motor full load amp (FLA) rating?  What would happen? Likely your circuit breaker would trip when the motor is turned on.  Electric motors have a higher current at start up.  This is sometimes referred to as inrush ....

Summary: You may be new to industrial controls and automation, but don't let that diminish you participation and ability to be confident.  By setting the right expectations and building a technical resource network, you have all you need to speak confidently about industrial controls. Introduction Are you a recent graduate about to start a new job? Or possibly you are changing industries and are new to industrial automation.  It can be very intimidating venturing into a new space where we don't have experience.  We have all been there. A lack of confidence shows up in your actions.  Humans seem to subconsciously detect when others lack confidence, which may result in some doubt in your response.  Confidence has a big impact on whether or not we perceive someone as trustworthy or an authority. You don't have to enter into a new job or a new industry as an expert before you can talk with others.  The good news is that you can speak confidently, despite h...

Which contactor is better - IEC, NEMA or Definite Purpose? Summary: The choice of contactor type depends most on who is making the decision, and what they value the most.  NEMA = ROBUST, Definite Purpose = "budget friendly", and IEC = versatile. There are reasons for three different types of contactors, and there are reasons one makes more sense than the other... depending on who you ask. What makes each type unique? NEMA - This type is the "tank" of the contactor world.  It is big, has large contacts that makes it capable of handling even severe applications.  NEMA devices are also easy to maintain - repair it and put it back into service.  I used to work in tech support for a market leader of NEMA motor control, and it was not unusual to hear of NEMA units operating for 40 years. Definite Purpose - As the name implies, this type has an intended use, and performs in that use well.  It has an attractive price point, but don't expect too much more of it though. D...

Summary: Sustainability is an objective that more and more companies desire to achieve, but it is not always easy to implement. The good news is that there is a simple substitution that can be made in control panels that will reduce CO2 emissions over the life of the equipment or machinery. What is the Secret? 🤯 The technology that enables this achievement is the electronic control coil on the contactor. Traditional contactors use a coil bobbin to generate a magnetic field when energized, which pulls the contacts together and completes the circuit to the electric motor. This does the job but requires continuous energy consumption while the contactor is operating. Contactors with electronic coils consume less energy. A circuit board more efficiently manages the magnetization and hold-in consumption. For example, a common 9 amp contactor with an electronic coil may consume 1.4 VA in the hold-in state, whereas a 9 amp contactor with a traditional bobbin would coil may consume 8 VA in...