Today's 'My Automation Education' is going to focus on a little piece of knowledge I learned this week while Altech was in our office. We're going to talk about circuit protection; the very basic beginnings of it. Why is circuit protection necessary? There are not tiny raiders coming to pillage your circuits while you are sleeping. Instead, the basic goal of circuit protection is to detect a fault condition and immediately cut electrical flow. Examples of these fault conditions would be overloads and short circuits. There are two basic types of circuit protection: fuses and circuit breakers. According to wikipedia: Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation. Circuit breakers are made in varying sizes, from small devices that protect an individual household appliance up to large switchgear designed to protect high voltage circuits feeding an entire city. Today we will focus on circuit breakers.
One very popular line sold at Marshall Wolf Automation is from Altech. They offer three solutions to myriad circuit protection needs. Lets break down their offerings:
UR Series - UL1077 Recognized Supplementary Protectors
This line provides only overload protection. They are available in both 277V AC and 480Y/277 V AC voltage ratings. They come in 1, 2, or 3 pole and offer 0.5-60 amps in B, C, and D trip curves.
V-EA Series - UL508 Listed Manual Motor Controllers
This line provides overload protection, as well as switching and disconnect functions. This allows you to use them as a motor disconnect so you can safely work on a single segment of your line without having to shut off your entire main breaker. They are available in 277V AC, 480Y/277 V AC, 42V DC, 80V DC, 24V DC, and 60V DC voltage ratings. They are offered in a variety of amperages from 0.3-60amps (1, 2, or 3 pole depending on voltage rating) and come in 6 (B, C, D, E, G, and Z) trip curves. They are an excellent option for applications where UL1077 is not enough and UL489 is just over kill.
UL (AC), DL (DC) Series - UL489 Miniature Molded Case Circuit Breakers
This line offers the overload protection, switching and disconnect functions, of the UL508 but also adds short circuit protection. They are available in 240V AC, 277V AC and 480Y/277V AC voltage ratings in ranges of 0.3-63 amps in 1, 2, or 3 poles for 4 (B, C, D, and Z) trip curves.
The potential down time from unprotected circuits is not worth the relatively low cost of installing them. Call and speak with our technical department to find the correct fit for your application, or check out our website to see for yourself. Marshall Wolf Automation should be the #1 choice as your industrial automation distributor.