Why use an E300 overload relay? 

GERRIE ROCKWELL AUTOMATION GROUP - Industrial Components - Sept 2020

By Joe Daley 

e300 build

What is an overload you ask?

An overload relay is a device that exclusively protects motors from overload conditions. Inductive motors are the workhorse of any industry, and anything moving in an industrial plant is driven by a motor of some kind. These types of motors are what we call ‘dumb devices’. Once powered on, all they want to do is run at the speed they are rated for and will go to any length to do so, even if that means its own self destruction.

For example, a motor driving a conveyor rated to carry a 10lb object may suddenly have a 50lb object placed on it. The motor then draws more current, causing it to heat up and eventually fail; hence why overload relays are required for both motor protection and by the Canadian Electrical Code.

When we look at today’s overloads there are many to choose from; there is bi-metallic, electronic and even smart electronic relays.

But what advantages do a smart overload relay really provide?

In today’s industry, machine uptime and production are vital to any operation. Every time a motor stops due to an overload, the questions is asked, “Why did that relay trip”? Now, if you only have a basic overload relay, diagnosing or troubleshooting a potential problem is quite challenging.

Smart overload relays offer diagnostic functionality where voltage, current, power consumption, and power factor can be monitored. The E300 relay goes even further to offer trip snapshot diagnostics, where it will take a picture of several monitoring parameters in the event of a trip. Examining the snapshot parameters can be of great help in answering that ever so vital question, “Why?”, and in a very short period too.

Smart overload relays offer ethernet IP communication for ease of integration into a control system. The data that is produced from the overload can be stored and made into meaningful reports which can later be examined.

Now your overload relay, which traditionally was a reactive device, has become a proactive device. As the smart overload allows you to monitor the current and power draw of the motor it’s protecting, the slight current draw increase could be a sign to schedule maintenance. Additionally, it can also monitor the number of hours the motor has been running for.

In today’s ever evolving industry, the importance of machine uptime is more critical than ever. And what were considered simple machines aren’t so simple anymore as the demand for more and more intelligence comes built in. These devices can even monitor themselves and send alarms to a control center when problems arise.

If you would like more information on the E300 Overload relay, please contact your local Gerrie Electric Branch. We’d be happy to help.

And remember “Every Process Starts with a Push Button”.

Let's chat again soon.

Joe image

About The Author

Joe Daley is our Industrial Control Product Manager and with over 20 years in the industry he is our encyclopedia of knowledge with Industrial Component applications.

Passionately Helping Customers Be More Successful By Delivering Exceptional Experiences