1. Prototype Development of Automated Ring Main Unit System
TNB Distribution Presentation Meeting

2. Project Background

3. RMUs Presently Used What is an RMU? Who operates it?
Are there safety concerns?

4. RMU Operation
Opening/closing of the load break switch or earthing switch:
Key/lever
Pushed to overcome spring force
Turn 90˚ at ~20 N.m (clockwise or counter-clockwise depending on usage)
Who operates it?
Are there safety concerns?
Can it function remotely?

5. Project Objectives
To design a motorized retrofit for automatic operation of (F&G*) Ring Main Unit (RMU) as per technical specifications provided by TNB Distribution.

6. Customer Requirements??

7. Deliverables
A prototype RMU Motorization Unit for operation of manually operated F&G* Ring Main Units.

8. Project Impact
The proposed system would be able to switch the RMU breakers in a safe manner via remote control.
Reduce downtime via remote operation and enhance the safety of TNB’s personnel by eliminating the need for manual operation of the RMU.

9. Project Methodology Stages of prototype development:
Torque and dimension measurements
Study of Actuation Mechanism
Grip frame design and material selection
Sensors & Alignment
Power & Controls
Testing & Trials

10. RMU Automation Operational Block Diagram
Auto/Remote
Manual push
relays &
Indicators
Local/Manual CW
Local/Manual
CCW M1
Power Supply Unit
Motor Driver w max current limit M2
28VDC 10A
CW/CCW
control signal M3
Microcontroller
Load switch limit switch
SCADA

11. Components List Power supply unit Grip Frame
Motor Mounting Rails Assembly
Programmable Logic Controller
Motor Driver/controller
Auto/Manual Cam Selector Switch
Push Power Relays
Limit/position Sensors
Geared DC Motors
Miscellaneous

12. Features
Light-weight (require only one person for mounting & installation)
Simple gripping and holding mechanism
Ready for remote and local operation
Completely detachable motor unit for manual operation
Continuous Breaker load switch status indicator
Motor over-current protection
Response time of < 5 seconds
Motor interlock operation

13. Estimated Costing* per 2+1 RMU (3 motor set)
Mechanical works (motor mounting and grip frame) – ~ RM1300
Geared motors – 3 x RM700
Controller – RM400
Motor driver – RM700
Sensors and electronics components – RM400
Power Supply Unit – RM900 (for prototype only)
TOTAL COST – ~RM5000 (without PSU)
* For large quantities of order

14. Initial survey and testing in ILSAS
Load breaker switch sizing
Initial motor selection

15. Continuation of motor selection
Motor mount and torque testing

16. Testing torque capability
DC Motor on mount

17. A closer look at the
Motor Mounting Rail Assembly

18. Further testing on actual F&G RMU

19. Procurement of Test Bed RMU

20. Installation of Mount on Grip Frame

21. Motor mount installed on grip frame on an F&G RMU

22. Rear view of gripping clamp

23. F&G ZZTT and ZZT RMUs in UNITEN
ZZT F&G RMU
ZZTT F&G RMU

24. Grip Frame

25. Detachable Motor Mounting Rail Assembly

26. Motor Selection and Testing – ILSAS
30VDC Circuit Breaker Motor

27. Gearbox Failure – Specified Torque 25N-m

28. Switching Key Failure

29. Testing on RMUs in UNITEN

30. Motor Mounting Rail Assembly
Play Video

31. Motor Mounting Rail Assembly
Play Video

32. Questions & Discussions
Thank you.
Questions & Discussions

33. Timeline Month 1 Month 2 Month 3 Month 4 Actuation Mechanism Assy
Fabrication and assy
Test and Trials
Cross Slide Traversing Assy
Design and Procurement
Fabrication
Actuation and Cross slide integration
Sensors & Alignment
Selection
Procurement
Integration
Power & Controls System
Selection and Procurement
Programming
Networking and Communication
PDSB

34. Uniten Procurement Procedures
2. Prepare Tech. Spec.
1. Fill PR Form
Requestor
Officer-in-Charge approves requirements
availability of budget
Finance verifies
Approval of PR
Approving Authority (PR) :
≤ RM 5K - Dean
≤ RM 100 K - TNC
> RM 100 K - NC
Quotation / Tender
Call for
Endorsement by
Dean / HOS
Evaluation with
Approval / Award
≤ RM 1 K - Dean
≤ RM 5 K - College Tender Committee
≤ RM 10 K - NC
≤ RM 500 K - TNC(P) Tender Committee
Create PO
≤RM 5 K : Procurement Manager
≤ RM 100 K : TNC(P)
> RM 100 K : NC
Supplier delivers
product / provide
service
Quotation
Value: ≤ RM 100 K
Float period: days
Min. : 3 companies
Tender
Value: > RM 100 K
Float period: days
Min. : 5 companies