Select the Right Varistors for Overvoltage Circuit Protection | Circuit Breaker Parts

The varistor’s absorption of the transient energy during a surge event produces localized heating within the component, which eventually leads to its degradation. If left unprotected, the degradation of a varistor can increase heating and thermal runaway. As such, a growing number of varistor-based surge-protection devices offer a built-in thermal disconnect function. It provides added protection from catastrophic failures and fire hazards, even under extreme circumstances of varistor end-of-life or sustained overvoltage.

the scariest thing I have ever seen/been around was in a fuel terminal at an oil refinery. I couldn’t figure out why we had printers, plotters, Apple II’s and monitors dropping like flies.

Centered to the right of the lens in the photo above is the lens release button, while the depth-of-field preview button is positioned snugly at the bottom left corner of the lens mount. A small plastic panel in the handgrip conceals the infrared remote control sensor at top, and the self-timer lamp beneath. Directly beneath the shutter button and power switch is the control dial, used to make adjustments to exposure and variables and menu options.

“To get 120 watts at 12 volts requires thick wires that can handle 10 amps, whereas at 120V, tiny 1A wires will do”.

I’m always a little torn over really small camera bodies, as it can be uncomfortable to twist my longer-than-average fingers around a small handgrip. That said, I really didn’t find the smallish grip on the Sony A55 too objectionable. The design of the front grip naturally encourages my middle and third fingers to curve downward, my pinkie to fold underneath the body, and to carry the weight of the camera on my middle finger, between the second and third knuckle. My customary two-handed SLR grip, with one hand on the lens’ zoom ring made for a comfortable and secure hold.

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CARRIER TAG: A data tag showing a 50-amp max breaker with a 31.4 minimum ampacity, which still allows a No. 10 circuit with a 75°C wire and termination rating.

Take a look at the Lennox air conditioning condensing unit tag on Page 19. Notice that the MCA is 28.6 amps and the maximum fuse or circuit breaker is 50 amps. This means it is allowable to install this unit on a circuit breaker rated at 50 amps and a conductor rated at 28.6 amps, according to the NEC’s NFPA 70.

Nah, they’re just creating the latest OpenSource platform as Arduino LCC, Arduino iso, Arduino Inc and Arduino & Co. fight over which is the real Shady.

Not to be argumentative, but please show me a case in which a H/O policy denied coverage for a fire loss because the homeowner used a non-UL listed device. H/O policies are contracts, strictly regulated by each state’s insurance department. The vast majority of H/O policies are “All Risk” based, meaning that you are covered for everything unless there is a specific exclusion for it. I have read many times on this forum and others about H/O policies not covering such claims, please show me ONE that actually is true. There may be one out there, but I have never seen it.

I use a variety of a/c and dc fostek ssrs. I have yet to have a problem, but i use them in circuits where 50% of their rated current is the absolute maximum they will ever see.

I can’t remember the exact numbers, but before the change, UK mains voltage was acceptable between something like 210V and 270V, depending on grid load. EU mains had a similar range. All they did, was tighten up the range. So now it’s nominally 230V, with 240V being within acceptable range. Which is good because the voltage stayed exactly the same. They just trimmed the range at the top end to be within the EU standards.