Electrical Inspection Explained
Electrical Inspection Explained
Everything you have ever needed to know about electrical inspections…
Electrical Inspection Explained
The scope of work involved in the electrical testing and inspection of a medium voltage installation by a visiting engineer can be listed and explained as follows:
It is generally recommended that at least two separate electrical inspections are carried out every month, by a competent party, as per the Electricity Regulations (1994).
The visiting engineer must measure to ensure the incoming voltage from TNB is within the permissible range (+5% & -10%), for each installation. If in doubt, he can seek the help from registered testers, to apply prudent testing and measurement.
He or she must also check to ensure all switchgear; transformers, cables etc. are in good condition for a safe working environment. This is a visual check, and dependent on the engineers past experience, in similar installations, to detect any abnormal conditions.
If in doubt, he can recommend that the client engage the services of a registered electrical testing company to come to site to carry out the Electrical Testing for all Switchgears, including Inspection for signs of arcing and Inspection for high moisture.
The visiting engineer may request the latest electricity bill so that he (or she) can compute the power factor, and also compare the TNB kWh meter and consumer meter to ensure the consumer is being billed correctly every month.
For the capacitor bank, he must check for faulty capacitors and or contactors, to ensure the power factor is maintained above 0.84. This will prevent any penalty charge from being imposed by the Power Company for low power factor. For Power Transformers, the visiting engineer can carry out the visual Inspection of HV and LV bushings for signs of cracks or other defects.
The engineer can take the physical temperature readings of the transformer windings, to monitor that it is within permissible range. He can also check for oil leaks at any joints of the transformer as well as ask the owner to engage a licensed company to do the testing and measurement of the insulation resistance of cables.
For Protection Relays, the visiting engineer will remind the client for the inspection and test of these protection relays every 2 years, as required by law. During such relay testing and recalibration, we will advise that the tester also check for good discrimination settings.
For the connection of the Earthing System, it is important to conduct tests and measurements, for the verification of results for earth, continuity, impedance and physical checking of earthing copper rods.
For the DC Charger and cells, it is important to ensure the battery is in good condition as well as the ensure DC Supply within permissible range for relay auxiliary supply and shunt trip coil.
In general for the Medium Voltage room, the visiting engineer will have to ensure that there is proper ventilation, that the room must be kept dry, as well as free from miscellaneous items. This room cannot be used as a store, and must be free from any pests and vermin that may access the live switchgear.
A final check is made of all the remaining safety requirements e.g. fire extinguishers, adequate normal and emergency lighting, rubber mats in front of panels, main entrance door to be locked to prevent unauthorized entry, as well as the overall cleanliness.
The visiting engineer will also provide an Inspection Report, called a ‘Borang I’, within 2 weeks of the Inspection.
This Borang ‘I’ is a declaration that the installation is fit to continue operations, and MUST be signed by a competent person, as stipulated by the Electricity Regulations (1994).
Send Us a Message
Electrical Inspection Explained
The scope of work involved in the electrical testing and inspection of a medium voltage installation by a visiting engineer can be listed and explained as follows:
It is generally recommended that at least two separate electrical inspections are carried out every month, by a competent party, as per the Electricity Regulations (1994).
The visiting engineer must measure to ensure the incoming voltage from TNB is within the permissible range (+5% & -10%), for each installation. If in doubt, he can seek the help from registered testers, to apply prudent testing and measurement.
He or she must also check to ensure all switchgear; transformers, cables etc. are in good condition for a safe working environment. This is a visual check, and dependent on the engineers past experience, in similar installations, to detect any abnormal conditions.
If in doubt, he can recommend that the client engage the services of a registered electrical testing company to come to site to carry out the Electrical Testing for all Switchgears, including Inspection for signs of arcing and Inspection for high moisture.
The visiting engineer may request the latest electricity bill so that he (or she) can compute the power factor, and also compare the TNB kWh meter and consumer meter to ensure the consumer is being billed correctly every month.
For the capacitor bank, he must check for faulty capacitors and or contactors, to ensure the power factor is maintained above 0.84. This will prevent any penalty charge from being imposed by the Power Company for low power factor. For Power Transformers, the visiting engineer can carry out the visual Inspection of HV and LV bushings for signs of cracks or other defects.
The engineer can take the physical temperature readings of the transformer windings, to monitor that it is within permissible range. He can also check for oil leaks at any joints of the transformer as well as ask the owner to engage a licensed company to do the testing and measurement of the insulation resistance of cables.
For Protection Relays, the visiting engineer will remind the client for the inspection and test of these protection relays every 2 years, as required by law. During such relay testing and recalibration, we will advise that the tester also check for good discrimination settings.
For the connection of the Earthing System, it is important to conduct tests and measurements, for the verification of results for earth, continuity, impedance and physical checking of earthing copper rods.
For the DC Charger and cells, it is important to ensure the battery is in good condition as well as the ensure DC Supply within permissible range for relay auxiliary supply and shunt trip coil.
In general for the Medium Voltage room, the visiting engineer will have to ensure that there is proper ventilation, that the room must be kept dry, as well as free from miscellaneous items. This room cannot be used as a store, and must be free from any pests and vermin that may access the live switchgear.
A final check is made of all the remaining safety requirements e.g. fire extinguishers, adequate normal and emergency lighting, rubber mats in front of panels, main entrance door to be locked to prevent unauthorized entry, as well as the overall cleanliness.
The visiting engineer will also provide an Inspection Report, called a ‘Borang I’, within 2 weeks of the Inspection.
This Borang ‘I’ is a declaration that the installation is fit to continue operations, and MUST be signed by a competent person, as stipulated by the Electricity Regulations (1994).
Send Us a Message
Electrical Inspection Explained
The scope of work involved in the electrical testing and inspection of a medium voltage installation by a visiting engineer can be listed and explained as follows:
It is generally recommended that at least two separate electrical inspections are carried out every month, by a competent party, as per the Electricity Regulations (1994).
The visiting engineer must measure to ensure the incoming voltage from TNB is within the permissible range (+5% & -10%), for each installation. If in doubt, he can seek the help from registered testers, to apply prudent testing and measurement.
He or she must also check to ensure all switchgear; transformers, cables etc. are in good condition for a safe working environment. This is a visual check, and dependent on the engineers past experience, in similar installations, to detect any abnormal conditions.
If in doubt, he can recommend that the client engage the services of a registered electrical testing company to come to site to carry out the Electrical Testing for all Switchgears, including Inspection for signs of arcing and Inspection for high moisture.
The visiting engineer may request the latest electricity bill so that he (or she) can compute the power factor, and also compare the TNB kWh meter and consumer meter to ensure the consumer is being billed correctly every month.
For the capacitor bank, he must check for faulty capacitors and or contactors, to ensure the power factor is maintained above 0.84. This will prevent any penalty charge from being imposed by the Power Company for low power factor. For Power Transformers, the visiting engineer can carry out the visual Inspection of HV and LV bushings for signs of cracks or other defects.
The engineer can take the physical temperature readings of the transformer windings, to monitor that it is within permissible range. He can also check for oil leaks at any joints of the transformer as well as ask the owner to engage a licensed company to do the testing and measurement of the insulation resistance of cables.
For Protection Relays, the visiting engineer will remind the client for the inspection and test of these protection relays every 2 years, as required by law. During such relay testing and recalibration, we will advise that the tester also check for good discrimination settings.
For the connection of the Earthing System, it is important to conduct tests and measurements, for the verification of results for earth, continuity, impedance and physical checking of earthing copper rods.
For the DC Charger and cells, it is important to ensure the battery is in good condition as well as the ensure DC Supply within permissible range for relay auxiliary supply and shunt trip coil.
In general for the Medium Voltage room, the visiting engineer will have to ensure that there is proper ventilation, that the room must be kept dry, as well as free from miscellaneous items. This room cannot be used as a store, and must be free from any pests and vermin that may access the live switchgear.
A final check is made of all the remaining safety requirements e.g. fire extinguishers, adequate normal and emergency lighting, rubber mats in front of panels, main entrance door to be locked to prevent unauthorized entry, as well as the overall cleanliness.
The visiting engineer will also provide an Inspection Report, called a ‘Borang I’, within 2 weeks of the Inspection.
This Borang ‘I’ is a declaration that the installation is fit to continue operations, and MUST be signed by a competent person, as stipulated by the Electricity Regulations (1994).