2014年6月29日 · I would say if it is marked 120 -277, that it is 120 through 277. If it is marked 120 / 277 it is either one or the other. That is how motors and other equipment is marked. For instance a motor marked 200-230/460 can be run on 200 through 230 …

2009年8月21日 · For example a ballast that uses 29.8 watts on 277 volts, and 30.1 watts on 120 volts, would be described as "30 watts" on either voltage. If the building has 277/480 volt service with 120 volts being obtained from a transformer, then working lighting at 277 volts will avoid the losses of a few % in the transformer in addition.

2022年7月21日 · So you could put in a 100 watt 230 volt lamp on 120 volts and get similar light output to a 25 watt lamp but may never need to change the lamp in the lifetime of the installation in some cases. Then there is mogul base lamps commonly available in 120, 240 and 277 volts, or at least once was.

2007年1月9日 · 120 / 240 single phase 120 / 208 three phase 120 / 240 three phase 277 / 480 three phase In my list, the first number (in blue) is the voltage from hot to neutral. The second number (red) is the voltage from hot - to - hot on the different phases. Some loads use all three phases, and no neutral. Some use a hot and a neutral, it depends on the load.

2009年11月12日 · The amperage chart on the ballast only indicated amperage draws at 120v or 277v not the other two. Generally all outdoor lighting (HID or Otherwise) is wired 120,277,208,240 or 480 etc. but most indoor lighting I have ever wired was 120 or 277v not 208 or 240.

2016年11月16日 · It does matter. 120-277V probably means that 220 or 208V is okay. If it said, 120 or 277V it would probably mean that 220 is NOT okay. But why risk a probably? Personally, I like to err on the side of safety.

2009年2月16日 · Also it is probable that the building has a 277/480 volt service with 120/208 or 120/240 being obtained from a transformer, in which case running the lighting at 277 volts will avoid transformer losses of a few % in addition. In total a saving of about 5% might be achieved, not worth the trouble for few lamps, but worthwhile for 1,000.

2021年1月29日 · 120 or 277v Fixture Calc. Thread starter Alwayslearningelec; Start date Jan 29, 2021; ... (74/120 or 74/ ...

2023年6月13日 · Let's say I have 277v site lights with 30 amp overcurrent protection and I want to install a 120v receptacle off of the 277v circuit. The receptacle is for cameras on the light poles. There will be one camera per light pole.

2006年12月27日 · Is there any rules of thumb that dictate whether you use a 480/277V vs. 208/120V three phase power system? Obviously the type of construction (industrial, commerical, office, residential) and the equipment installed would dictate which power system you choose. If theres no direct need for...