RMU Standard Operating Procedure (RMU SOP)

Purpose 

The objective of this procedure statement is to explain the work sequences and procedures that will be used to ensure the proper & safe operation of the RMU and Transformer.

Scope of Work

Ensure safe operation of RMU & Transformer.

Responsibility

1. Project Manager
2. Electrical Engineer
3. Safety Engineer

Reference 

1. Project specifications & approved drawings.
2. Project Quality Plan.
3. Health, safety, & environment manual.

Equipment Required

1. Ensure all personnel have proper PPE (Personal Protective Equipment).
2. Electrical Safety Shoes
3. Flame-Resistant Clothing
4. Safety Glasses or Goggles
5. Insulated Tools

Precaution

Ensure that the RMU & the space surrounding it are free of any impediments for inspection.

Procedure

Visual Inspection

• Visually check the RMU in search for any indications of damage, leakage, or conditions that are not typical.
• Analyze the RMU for any unnecessary objects which may be present.

Switching Operation

• It is important to adhere to the switching sequence that is specified in the operation handbook.
• When working with switches, make sure you use insulated tools.
• Before starting any work, make sure that proper isolation has been arranged.

Earthing

• Before starting any type of maintenance or switching procedures, make sure that the RMU has been properly earthed.
• Determine whether or not the earthing system is operating appropriately.

Normal Voltage	Medium Voltage	Low Voltage	Light Current
5 Ω	2 Ω	2 Ω	0.5 Ω

Communication

• Ensure that there is free and open communication with all of the personnel participating in the operation.
• When it comes to coordination, make use of the existing communication protocols.

Operation Steps of RMU

Turn On

• In the direction indicated by the arrow, turn the earthing switch so that it is disconnected.
• It is clear from the second panel that earthing switch is not connected.
• Place the handle on the panel of the circuit breaker & rotate it in the direction of the arrow, which indicates the direction of the energy storage.
• The final step is to finish the process of closing the ring main unit by pushing the green close button located in upper right corner of the screen.

Turn Off

• The first step is to disconnect low-voltage (LV) main circuit breaker. 
• The next step is to click the red stop button that is located in the upper right corner of the circuit breaker. 
• It has been determined that the circuit breaker has been disconnected, & the panel indicator of circuit breaker room has displayed the disconnected state. 
• The next step is to press the handle into the earthing switch room after inserting it. 
• The action of disconnecting ring network cabinet is finished when the arrow rotates in the direction of closing, which indicates that the earthing switch has been closed. 
• The panel also indicates that the earthing switch has been closed.

Power Transmission Procedure

• Verify that the primary load switch on the transformer’s output is off before turning it on.
• Remove the “No Switching On” warning sign and open earthing knife lock.
• To open earthing knife, turn counterclockwise.
• Verify that the earthing indication is in the “floating” or off position.
• The earthing knife lock should be locked.
• Unlock the load knife.
• To close the switch, turn it clockwise.
• Verify the three indication lights’ condition.
• Lock the load knife lock.

Power Failure Operating Procedure

• The transformer’s output total load switch needs to be unplugged before the transformer is turned off.
• Check the three indication lights’ condition.
• Unlock the load knife.
• Manually press the red “OFF” stop button until the switch sounds.
• Verify that all three of the indicator lights are white and not flickering.
• Lock the load knife lock.
• Open the earthing knife lock.
• Close the earthing knife by rotating it clockwise.
• Hang up a warning sign that reads “No Switching On” and make sure the earthing indicator is in earthing state.
• Lock the earthing knife lock.

Emergency Procedure

• In the case that any unusual conditions arise, you should be conversant with the emergency shutdown procedures.
• Every member of the staff should be informed of the protocols for responding to emergencies.

Post Operation Inspection

• Once the process has been finished, it is necessary to perform a visual inspection to ensure that all of the switches are in the appropriate position.
• Ensure that all of the precautionary measures have been carried out in the appropriate manner.

Documentation

• Please make sure to document all of the pertinent information pertaining to the operation, particularly any deviations from standard operating procedure.
• Ensure that records are kept for future use and for the purposes of auditing.

Training

• Make sure that all of the staff who are involved in the RMU operations have received sufficient training and are capable.
• Refresher training courses should be offered on a regular basis in order to emphasize safe operating procedures.

Closure

• Protect the RMU & the area immediately surrounding it.
• Make sure that all of the tools & equipment are stored in the appropriate manner.
• Complete any paperwork or reporting that may otherwise be required.