technical clarification_d & d _ bhadra.doc

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Technical Clarifications

Andritz Ref.No. BHEP/V-0230/HIP/SR-PM/TN/0070 dated 27.06.2012BHEP/V-0230/HIP/SR-PM/TN/0076 dated 21.07.2012

Date 05.08.2012 Sheet No. 1 of 6

Customer M/s KARNATAKA POWER CORPORATION LIMITEDCustomer ref. LOT/BHADRA/RBU/R&M/1112

Project BHADRA Project Code V-0230

Assembly D & DPanels

Drawing No. E4 V-0230 511/51201/02

S No. Customer ObservationAndritz Hydro Clarification

1. Drawing No. E4 V-0230 512 02 Control Philosophy of D & D

a)To provide Remote indications(ON & OFF) of pumps with alarm at control room for safeoperation/monitoring of the system

b)Thermal overload & phase failure relays shall be provided for drainage & dewateringpumps (Clause No. 3.47.03)

c)

To provide :-HRC fuses to AC circuit.Panel Heaters with thermostat control.10% spare terminal block for future use.

d)

2. Drawing No. E4 V-0230 512 01 D & D drawing

a)To provide backup HRC fuses in addition to MPCBs for individual motors to isolate duringrepair/maintenance

b)

Requirements:-When water level is below F1, all pumps will be off.At F2, pump1 will be in service.At F3, pump1 & 2 will be in service.At F4 pump1, 2& 3 will be in service.At F5, all pumps will be in service.


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Drawing No. E4 V-0230 511/51201/02

c)

As per working of Timers, the timer contacts NO & NC shown in Rev-0 may please beretained.

d)


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Drawing No. E4 V-0230 511/51201/02

S No. Customer Observation Andritz Hydro Clarification

c)

The current rating of 3 pole power contactors provided is equal to the rated current of thecorresponding motors. The power contactors of higher current rating considering 10%overload 5% tolerance shall be provided. At present, 2 Nos. of recently commissioned50HP submersible pumps installed at power house are carrying/taking continuous loadcurrent of 85Amps. As per the manufacturer specifications, the rated full load current is82Amps at 415Volts and 0.85 PF. Hence ratings of all the Power Contactors (Star-Delta) forall the Motors/submersible Pumps may be changed to 100Amps in order to havestandardization and stock of minimum spares.

Agreed. Revised documents shall be providedto you.

d)Sht. No. 3:In the legend, description for V, A, VSS, ACK PB & ASS may be indicated


e) Sht. No. 5:Refer grid reference A5, under the heading WIRING- Internal wiring will be done by Ringtype and Pin type lugs shall be replaced by Internal wiring will be done by Ring type andFlat type lugs.


f) Sht. No. 6:1) The ammeter & voltmeter shall be provided with communication

facilities/transducer

2) Ammeter shall be provided for each pump.

1) According to contract, no communicationfacilities will be provided.

2) Agreed. Single phase current measurementprovision will be provided.

g) Sht. No. 8:HRC fuses for backup protection shall be provided for all pumps.

We have already provided two protections. OneMCCB in main incomer and MPCB for individualmotors, so there is no need of HRC fuses.


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Drawing No. E4 V-0230 511/51201/02

h)

Sht. No. 13, 14:1) Details of Pump selection switch (SW1) shall be provided.

2) Details of Timers - T1 & T2 shall be provided.

3) At grid reference G3, it is observed that the NO contact of timer is to be replacedby NC contact. The same may be reviewed and implemented.

4) At grid reference G5, it is observed that the NC contact of timer is to be replacedby NO contact. The same may be reviewed and implemented

1) Kindly clarify, In manual mode how many

pumps will be ON at a time. If only one pumpwill be ON then Kaycee / Vaishno make 4position with OFF switch will be provided.

Formore than one pump, no switch will beprovided.

2) We will provide Star/Delta timer of EAPLmake. Model : A1DS

Contact Detail: 2NO 15,18 & 25,28

3) As per the working of timer, this contact willbe

NO only.4) Agreed. Revised documents shall beprovided

to you.

i)

Sht. No. 15, 16:1) Details of Timers- T3 & T4 shall be provided.2) At grid reference G3, it is observed that the NO contact of timer is to be replaced

by NC contact. The same may be reviewed and implemented.

3) At grid reference G5, it is observed that the NC contact of timer is to be replacedby NO contact. The same may be reviewed and implemented.

1) We will provide Star/Delta timer of EAPLmake. Model : A1DS

Contact Detail: 2NO 15,18 & 25,282) As per the working of timer, this contact willbe

NO only.3) Agreed. Revised documents shall beprovided

to you.

j)Sht. No. 20:

1) TBs provided for AC circuits shall be matched for the cable sizes of the respectivemotors. Details of TBs provided shall be furnished.

Stud type Elmex make TBsFor 6 to 35 sq. mm cable CBT M6S1For 2.5 to 6 sq. mm cable CAT M4


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Drawing No. E4 V-0230 511/51201/02

S No Customer Observation Andritz Hydro Clarification

3. Drawing No. E4 V-0230 511 01 Top cover drain system drawing

a) Sht. No. 5:Refer grid reference A5, under the heading WIRING- Internal wiring will be done by Ringtype and Pin type lugs shall be replaced by Internal wiring will be done by Ring type andFlat type lugs.


b) Sht. No. 7:1) HRC fuses for backup protection shall be provided for the drainage pump.

2) Details and specifications of 1KW Drainage pump shall be provided.

3) Please note that, existing 110V DC Top Cover Drainage Pumps are of compound DC

type, using rheostat in series (smooth starter circuit) and with No Volt Relay forField Failure protection. All these control equipments/protections may please beincorporated in the scheme drawings, if the same type or existing DC Motors areused.

1) We have already provided two protections.One MCB for main incomer and one MCB formotor, so there is no need of HRC fuses.

2) Specification of 0.75KW motor has beenattached.

3) For 0.75KW motor, DOL starter will be

provided.There is no need of resistor for starting ofsuch

small rating motor.

c) Sht. No. 8:1) In grid reference D4, SW Auto manual selector switch shall be indicated properly.2) Ammeter shall be provided for the Top cover drainage pump motor.

1) Agreed2) AgreedRevised document will be provided to you.


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Drawing No. E4 V-0230 511/51201/02

d) Sht. No. 9 & 10:1) Alarm and indications for the maximum water Level may also be provided at

Control Room.1) Provision has already been provided in the

panel.Wiring from cubicle to control room is incustomer scope.

technical clarification_d & d _ bhadra.doc

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