Group 4 is two 120 Volt out of phase windings in open delta. Group 3 is two 120 Volt out of phase windings in open delta. The in-phase winding still produces rated current.Ĭonsider also that for use at the lower voltage, the windings may be broken into four groups. The rated current of a winding does not change.

When a manufacturer shows both a three phase rating and a single phase rating, the single phase rating is always 2/3 of the three phase rating. In the out of phase windings, 50 KVA at 50% PF = 25 kW. For a load of 100 kW the in-phase winding will supply 50 kW and each of the out of phase windings will supply 25 kW for a total of 100 kW. For a 100 KVA load, the load on each winding will be 50 KVA. Thus the in phase winding will share the current equally with the two out of phase windings.Įach winding has equal voltage and equal current so each winding has equal KVA. If you do a vector sum of the voltage drops of the two windings you will find that it is equal to the voltage drop of the inphase winding. The current will be leading at 50% PF in one winding and lagging at 50% PF in the other winding. Assign an arbitrary load load and impedance. Jimmy Carter RE: 12 wire generator wired for single phase operation JohnMcNutt (Industrial) 11 Feb 18 06:35Ĭonsider the out of phase windings taken alone as an open delta. You will have three wire single phase power from L1 to Neutral to L2. For the lower voltage connections this will be two leads.Ĥ> Reconnect the remaining wires to the neutral terminal.ĥ> The wire or wires removed from the neutral terminal and which have continuity to L2 are now connected to 元 and insulated. I prefer the Zig-Zag connection because of the ease of conversion even without wire markers.ġ> Arbitrarily label the outgoing leads as L1, L2, 元.ģ> Find continuity from L2 to the neutral. Typically from 80% to 120% of KVA capacity.ĭon't confuse the Zig-Zag grounding transformer with the Zig-Zag generator conversion. KW capacity is 150% of the original capacity. KVA capacity after conversion is 2/3rds of the original capacity. Then the Double Delta became more common.

Operation zigzag