JacksonburgFarmer
Senior Member
- Location
- Butler County Ohio
One of our bigger customers has 2 open delta 3 phase 240V services to their facility. (Grain elevator)
Has anyone ever seen what could posibly cause a Open delta 3phase service to have balanced voltages. (A to ground 118V ,B to ground 205v, C to ground 118v. A to B 235v, A to C 240V, B to C 233V), and have amperages NO WHERE NEAR BALANCED.....A single load, a three phase 230V motor 50hp running w/ idle load A 54amps, B 52amps, C 17 amps..... Yes C phase at 17 amps. It is not only this motor, every motor in the facility that is 3 phase does the same exact thing. Readings taken in MDP 4 feet from CT cabinet. Local POCO says that this "can happen" with open deltas. This has been this way since the service was put in in 1987. I have been working in this facility for 3 years. Up untill now there was no concern from customer. Now they want to put in some soft start controllers....the low c phase amperage causes the controller to drop out due to suspected phase loss......Any ideas???
Has anyone ever seen what could posibly cause a Open delta 3phase service to have balanced voltages. (A to ground 118V ,B to ground 205v, C to ground 118v. A to B 235v, A to C 240V, B to C 233V), and have amperages NO WHERE NEAR BALANCED.....A single load, a three phase 230V motor 50hp running w/ idle load A 54amps, B 52amps, C 17 amps..... Yes C phase at 17 amps. It is not only this motor, every motor in the facility that is 3 phase does the same exact thing. Readings taken in MDP 4 feet from CT cabinet. Local POCO says that this "can happen" with open deltas. This has been this way since the service was put in in 1987. I have been working in this facility for 3 years. Up untill now there was no concern from customer. Now they want to put in some soft start controllers....the low c phase amperage causes the controller to drop out due to suspected phase loss......Any ideas???