phase sequence

You can not hook the gen sets or multiple gen sets into parallel operation to be coupled in substation bus bars unless you meet the criteria.

1. Must be the same phase sequence.

2. Must be the same voltages.

3. Must be the same frequency.

Aren't you aware of the Dark Lamp method or the Bright Lamp method? If the phase sequence is different it would indicate in any of the above methods.

The most safe method is Dark lamp or Bright lamp method as mentioned by electricalexpert65.

Other PLC methods can be used for the perfect generators, of which in the factory performance and no doubt of their communication with each other. And therefore paralleling can be achieved automatically without any person to help.

If you are in doubt with your generators, you must first use the old and safe method to approve if they are O.K and suitable for automatically paralleling.

thxxxx..... kindly tell me the procedure??

This is the dark lamp connection. lamps are connected across the same phase side of the common busbar. (R to R, S to S and T to T

Lamps will be on an off successively and later When the both lamps go dark, it is considered that two side of each lamp group is in the same phase and same angle.

Then you can make both switches on, providing the lamps stay off at least 3 seconds.

In the event the generators, to be paralleled, are more than two, then it is a good way to synchronize each generator directly to the common busbar. In this case one sides of each lamp group must be connected to the busbar, and the other side to the generator to be synchronized.

Bright lamp connection is almost the same, except the lamps are connected on different phases.

Well it seems dark lamp method anold fashoin way i did it many times meaning having the lamps of equal wattage put on the same impressed voltage gives the same brightness. Nowadays we are using PLC then.

I can suggest more practical way,if you can isolate bus section and put only one generator on it and start any one motor if it rotate in same direction as with other generator phase sequence is OK