Suitability of a Switchgear

There is a 3.3kV switchgear of the following details:

a. Double Incomer,3.3kV,2000A,228MVA,1Sec consisting of 26 Outgoing panels/Loads.

b. Full load Ammeter reading of 3.3kv incomers of existing switch board :(CT ratio is 1750/1A)

I/C-I-----Ammeter Reading: 695Amps, I/C-II----Ammeter Reading:28.36Amps, Bus coupler B/C-----OFF )

c. K-Factor of 2 nos identical Incomer (I/C) Transformers is : 4 2. T/R Rating: 10MVA, Primary/Secondary : (524.9/1668.6 Amps) , Vector Group : Dyn11 5.O/C setting : (Plug setting k=1.75). Name plate details: delta/star,11/3.48kV,10MVA,Dyn11,Z=8.35%,I/c cable size:2x(3cX400sqmm),NGR=2.54 ohms,750A,10Sec.

There is a proposal to add 4 motors of range of 150kW and 2 nos motors of range 260kW to the switch gear ( loads equally distributed on both incomers) . At present there is a exising highload on the incomer-I of the Switch board of 3.3MW capacity gas compressor motor presently being started by auto transformer starter.The name plate details are (kW Rating:3300,Working Current: 600A,Full Load Current: 661A,Stator Voltage:3300,Duty:Continious,Speed: 1490 Rpm) and also an additional load of 2.2 MW is being added in Incomer-II ( by the user/ other than myself).

The remaining loads (FLCs) in the swithgear are as below ( Suffix A refers to I/c-1 and B refers to I/C-2) & remaining panels are spares :

Note: Motor B is standby to motor A.

1. 04-PM-51A & B (60A)

2. 04-KM-02 (48A)

3. 46-PM-03C & D(35A)

4. 46-PM-02A & B(95A)

5. 42-PM-17A & B (54A)

6 .42-PM-17A & B(54A)

7. 42-PM-02A & B 169A)

8. 42-PM-01A & B (164A)

Question: 1. Shall the switchgear be suitable/adequate to cater for the new loads ?? (4 motors of range of 150kW and 2 nos motors of range 260kW)

2. Is the Starting & full load torque requirement for gas compressor driven by auto start 3.3 MW motor really required to arrive at this calculation??

3. Sparing the new loads, Is the switchgear suitable for the inclusion of 2.2 MW load??

Pratap