Scribd
Upload
9 views1 page

MUBASHIR

The document compares Neutral Earthing Transformers (NET) and Neutral Grounding Resistors (NGR) in electrical systems. NET provides a ground path for ungrounded systems, preventing neutral floating and ensuring safety during faults, while NGR limits fault current and protects star-connected generators or transformers by converting excess voltage into heat. Both play crucial roles in maintaining system integrity and safety in electrical installations.

Uploaded by

abdul sami
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
9 views1 page

MUBASHIR

The document compares Neutral Earthing Transformers (NET) and Neutral Grounding Resistors (NGR) in electrical systems. NET provides a ground path for ungrounded systems, preventing neutral floating and ensuring safety during faults, while NGR limits fault current and protects star-connected generators or transformers by converting excess voltage into heat. Both play crucial roles in maintaining system integrity and safety in electrical installations.

Uploaded by

abdul sami
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
You are on page 1/ 1

Report Submitted by M.

Mubashir Khanzada

Difference b/w NET (Neutral Earthing Transformer) and


NGR (Neutral Grounding Resistor)

Neutral Earthing Transformer:


Transformers are an essential part of any electrical system. it is important to ensure the safety of the
equipment and the people using it, one important aspect is earthing the transformer neutral. NET is used to
provide a ground path to ungrounded or impedance-grounded electrical systems. It is typically connected
between the neutral point of a power system and ground.

Importance:
Grounding the transformer neutral is essential for a number of reasons. Firstly, it provides a safe path for
the current to flow in case of a fault.
1. It prevents the system from Neutral Floating condition (Neutral point isn’t at zero Potential)
2. Ground Fault Detection
3. If the power system is in delta configuration, we will use NET to provide earthing to entire power
system by connecting neutral point of star configuration with ground or it’s used where system is in
Y configuration, but it’s not earthed.
4. To provide single phase from delta connected system by taking neutral and phase wire
5. If the neutral is not grounded, it can lead to insulation breakdown, resulting in damage to the
transformer. This can be costly to repair or replace and can cause disruption to the electrical
system.
6. If the neutral is not grounded, there is a risk of overvoltage, which can damage equipment and lead
to the malfunctioning of the system. In addition, protection devices such as fuses and circuit
breakers may not operate properly, leading to damage to equipment and a safety hazard to people.
Type of grounding
i. Solidly
ii. Current limiting device (resistor)

Neutral grounding resistor:


NGR are used in electrical power system to protect the star connected generator or transformer. NGR is
constructed by inserting resistance bank b/w neutral and ground. If any faults occur in it passes through
resistance bank from neutral terminal of star then voltage will be dropped and convert in form of heat by
passing through it.

Importance:
1. Limits the fault current
2. Measure fault current by NCT
3. in case of arc fault, we can limit magnitude of current with NGT
value of resistance depends on fault current rating and type of System

You might also like