Medios y materiales para la enseñanza-aprendizaje de las carreras de fondo

DEWA Metering /control room

Party’s HV switchgear

DEWA point of supply/responsibility.

Party’s Switchgear shall be suitable for termination of 3X240 /300sq.mm

XLPE/PVC/SWA/PE Aluminium/Cu cable with heat shrinkable type cable terminations.

Termination at party’s switchgear incomer has to be done by party and terminations at DEWA RMU will be done by DEWA.

Paage 1 of 2

(DEWA Meter/Control room)

1. Size of the Control/Metering room (DEWA RMU room) shall be approximately 5.4 x 5.4 mtrs.(29.16 sqm) for regular type RMU room made of block work and RCC slab. This is for 2 Nos. 11KV feeders

2. For additional feeder (3^rd) additional space required approx 10 sqm( i.e. for each additional panel 10 sq mtr is required). Please note that the area of the

Control/Metering, shall be decided only after approving the 11kV feeder arrangement (HV SLD)

3. Control/Metering room clear height shall be 3.65 mtrs. Or 12’ .

4. Control/Metering room door clear height should be 2.75 mtrs or 9’ and clear width of 2.44 mtrs or 8’.

5. Control/Metering room must have cross ventilation (2 sides) with aluminum louvers / doors

6. 95cm of clear depth from finished floor level (FFL) to be provided for trench and for cable entry to the Control/Metering room.

7. FFL of the Control/Metering room should be higher (15cm to 30cm) with respect to adjacent ground level (on the other side of substation door).

8. Party’s Switchgear shall be suitable for termination of 3X240 sq.mm

XLPE/PVC/SWA/PE Aluminium/Cu cable with heat shrinkable type cable terminations.

Termination at party’s switchgear incomer has to be done by party and terminations at DEWA RMU will be done by DEWA.

Note :

Sikka / road should have a minimum clear width of 6.1m. However if the proposed substation space is less than 12m away from the main road then the sikka should have minimum clear width of 3.05m.

Guide Lines for Protection Requirement for Private Substations

1. The designer shall provide all the necessary protection to ensure that a private substation will not have any negative impact on the DEWA system.

2. Suitable protection and interlocking shall be provided.

3. There should be sufficient discrimination between DEWA protection and that of the private substation so that the protection at private substation operates earlier to the DEWA protection during fault.

4. In substations with multiple switchboards, the interlock shall be extended to all the switchboards.

5. The drawings shall use ANSI standard codes for depicting protection relay functions as well as contain a legend.

6. The incomer protection relays shall comply with IEC 60255 and be supported by type test and guaranteed routine manufacture’s works test certificates. Only certificates confirming that the relay has passed the type tests needs to be submitted to DEWA.

7. The incomer should have over current and earth fault protection and these should be clearly shown on the drawing.

8. The over current relay shall operate correctly for fault currents up to 25 kA.

9. Under voltage protection shall be provided as per S8 of the DEWA Regulations for Electrical Installations.

10. Details on the relay and current transformer shall be mentioned on the drawing. Only the test certificate needs to be submitted to DEWA

11. The instrument transformers shall comply with IEC 60044 and be supported by type test certificates and guaranteed routine manufacture’s works test certificates. Only certificates confirming that the current transformers have passed the type tests needs to be submitted to DEWA

12. The incomer current transformer shall be dimensioned so that the protection scheme will operate effectively for a fault current of 25 kA.

13. Mechanical and electrical interlocks shall be provided so that the incomers cannot be paralleled. Both mechanical and electrical interlocks shall be shown on the drawings.

14. Power factor correction capacitors shall be provided as required by S8 of the DEWA Regulations for Electrical Installations.

15. Motor starting currents shall be shown on the drawings. Starting currents shall be in accordance with S4.6.10 of the DEWA regulations for Electrical Installations 1997.

16. Reverse power protection shall be provided to ensure that in-feeds to faults within the DEWA 11-22 kV network are cleared within 3 seconds.

17.The developer should submit the completed checklist with the single line diagram.

Sample operation philosophy (Interlocking arrangement)

Sl.No. Condition IC-1 Bus coupler IC-2

1 Normal I O I

2 Loss of Incomer-1 O I I

3 Loss of Incomer-2 I I O

Legend: I = close, O = open, IC= Party’s incomer breaker

PART-I (Space open to sky)

1. Size of the RMU foundation shall be 6.1 X 6.1 mtrs.(37.21 sqm) with FGRP Kiosk (to be supplied by DEWA). This is for 2 Nos. 11KV feeders.

2. For additional feeder additional space required same as above.

3. The height of the boundary wall (3 sides) around the RMU foundation substation shall be not more than 7’-0”.

4. RMU space should be directly located on DM Road / Sikka

PART-II (Building room)

9. RMU room should be directly located on DM Road / Sikka

10. Size of the RMU room shall be approximately 5.4 x 5.4 mtrs.(29.16 sqm) for regular type RMU room made of block work and RCC slab. This is for 2 Nos. 11KV feeders

11. For additional feeder (3^rd) additional space required approx 3.3 sqm( i.e. total 6.9 X 5.4 mtrs.).

4. For additional feeder(4^th) additional space is required approx 8 sqm(i.e. 7.5 X 5.4 Mtrs).

5. RMU room clear height shall be 12’ (for regular type RMU room made of block work and RCC slab).

6. RMU room door clear height should be 9’ and clear width of 8’.

7. RMU room must have cross ventilation (2 sides) with aluminum louvers / doors

8. 3’-2” of clear depth from finished floor level (FFL) to be provided for trench and for cable entry to the RMU room.

9. FFL of the RMU room should be higher (6” to 12”) with respect to adjacent ground level (on the other side of substation door).

Note : If RMU space/room is located on sikka, sikka should have a minimum clear width of 3.05 m as long as proposed substation is not more than 12m away from the main road. Otherwise, the sikka should have minimum clear width of 6.1m.