Auto Synchronising, Auto Load Sharing and AMF Panel
The panel illustrates the arrangements of an auto synchronise, auto load sharing and AMF requirement. Generally relays such as easy Gen 3200(Built by wood words) or TE808 (Built by cspc) are used. The photo shows the unit in service. Standard PLC Controls also could be used in place of relays.
Such relays are used on individual generator panel and additional relay arrangements supplemented. These relays have Controlsled 1 to 10V DC injections on the governor Controls and AVR Controls to rise or low the speeds of governor during start up as well as load shares however use of a quardratune CT for sync Balance is mandatory for synchronisation.

For the generator Controls motorised ACB/MCCB contactor is used on the phases only, contactors are used braking the neutral separately. This is in view of retaining only one neutral in the system to avoid circulating current. Some of the bigger stations use of a manual switches on the neutral also within practice.

These are the PLC based relays and also can be Controlsled by BMS.

The AMF arrangements used in this start the generator when public electric supply fails and puts it back on the same supply as it resumes without affecting any of the system and not bring DG supply on to user bus when public supply is available.

It also provide sufficient time (say 5 min) for cooling of DG system by keep running the general when public supply is also available but without switching on load to generate . Any number of generators of any capacity can be synchronized using these relays. Auto tripping of generators on emergency is also instituted. This is without time delays.

While we use such relays for auto purpose, during failure of such system manual synchronisation with manual governor and AVR Controlss become mandatory. Here again we use the dark lamp synchronisation together with double voltmeter, double frequency meter, synchroscope with transformers and check synchronisation relay we also use motorised potentiometers provide for the o -10V injection for governor and AVR for adjustment. Here load sharing is again purely manual use of RPR for manual purposes is must.

Generally these relays provide overload and general E/F protection as well as RPR. Backup breakers provide S/C protection. Hence external PRP and REF are recommended.

In all these cases where automation is used closing the breakers manually from the PB provided on the EB is strictly prohibited. Since breakers even though protected by u/v will close momentarily Parellis the two and hence the pre caution.

Purely manual operation of the generator when total relay fails is done only from the generator point.