480 or 240 3 phase for new service - Eng-Tips
2004年1月21日 · I think the choice really boils down to cost of materials and availability of equipment at the selected voltage. 240 3-phase is rare for new systems, but was very common in the U.S. 50+ years ago. 480 has become nearly standard practice in the U.S. for larger commercial and some industrial facilities that don't justify higher voltage. 208 is ...
480 v. 277 V clarification? - Electric power & transmission ... - Eng …
2003年6月9日 · Voltages are designated as something like 277Y/480, 3 phase or 120Y/208 V 3 phase. If your looking at a lighting panel (like what is in your house), it is usually single phase 120/240 V. Some ways to detect 3 phase - the higher voltage will be the lower voltage times SQRT 3 and 3 phase is usually on a motor control center or switch.
480V 3-Phase circuit supplying three single phase-phase loads 2
2024年10月31日 · I have a 3-phase (3 pole wye connected) 480V circuit breaker that I need to supply three 200kVA single phase 480V identical loads (A-B, C-A, B-C). Only two legs are used for load. As we know, in a balanced 3 phase system, the current across all three phases is kVA / 480V / sqrt(3). This means it would be 600kVA / 480V / sqrt(3) = 722A.
how to run a 480 Volt 3 phase motor on 240 volt single phase …
2023年7月6日 · If 1/2 rated sped is enough, use a VFD rated for 240 Volt single phase input. If you need full speed, use a VFD rated for 240 Volt or 480 Volt single phase input and a 240v/480V transformer. If the transformer is on the input, it will be a single phase transformer. If the transformer is on the VFD output it will be a three phase transformer.
Converting 480 three phase to 240 single phase and possible
2013年6月10日 · One way of deriving single phase from three phase often used on smaller generator sets is the zig-zag connection. (Not to be confused with the zig-zag grounding transformer. This would give true, 120-240 Volts with no phase shift between the 120 Volt legs. The down side: Your power factors for a resistive load on the three primary phases will be:
480v 3 phase - Canada - Issues - Eng-Tips
2006年3月16日 · The big 3 phase 480v things are a fan motor and controls, a duct heater and thyristor, and a large peristaltic pump and controls. We also have a 240v HVAC system in the control container. We have put 8 weeks of time in to the preliminary design which has to be submitted on Friday, all based on the 480v supply.
three phase vs. single phase light load calculations.
2004年4月30日 · The distance is 250' from the 480 3 phase panelboard to the first tower, then 500' more to the last tower. At each tower base, is a backboard with a 60 amp 3 pole 480 v fusible disconnect tapped from the (3) 2/0 copper wire that is run from the main panelboard to the first tower and then on to the 2nd tower.
Colour codes USA 3 phase - Eng-Tips
2003年7月1日 · On a 4-wire, delta-connected system where the midpoint of one phase winding is grounded to supply lighting and similar loads, the conductor or busbar having the higher phase voltage to ground shall be durably and permanently marked by an outer finish that is orange in color or by other effective means. 424.35 Marking of Heating Cables.
100 Hp 480 volt 3 phase pump motor - Eng-Tips
2006年7月12日 · RE: 100 Hp 480 volt 3 phase pump motor jraef (Electrical) 15 Jul 06 00:25 If I wewre to guess (and I am as I type), I'd say this was a 2 transformer open delta system (a.k.a. "V-Phase), very common for remote aggricultural pump systems where the utility didn't want to run all 3 wires a long distance for one load.
Connecting a 3-phase 480 V Delta Motor w. a 3-Phase 480Y
2003年5月29日 · These are rare and it is unfeasible for us to stock, so we decided to provide them with a 3-phase 480Y/277V connection. Has anyone experienced any problems with connecting a 3-phase 480 volt delta motor w. a 3-phase 480Y/277V xfmr? The motor has a soft start and a breaker to protect from motor faults (phase imbalance).