Since 1983, Acutran Transformers  has been design and manufacturing neutral grounding in either individual transformer components or in a complete neutral grounding system.

What is a Neutral Grounding Transformer (aka Earthing Transformer)?

A neutral grounding transformer (NGT) or earthing transformer is a single phase transformer used with a neutral grounding resistor to provide high resistance grounding by connect between the Wye Connection of a power generator and the ground.

For continuous time ratings, the Neutral Grounding transformer must be designed to withstanding the rated current for an indefinite period of time; therefore, the KVA rating of the grounding transformer is equal to the rated line-to-neutral voltage times the desired neutral current.   For a short-time rating, the KVA rating of a grounding transformer will be smaller because the unit is designed to carry its rated current for a limited time.

A standard application is normally designed to limit the line-to-ground fault current to below 15 amps for generators rated up to 14,400 volts.  Acutran NGTs will provide a high resistance neutral during a fault condition, while allowing the system to operate as an ungrounded system during normal operating conditions.

Acutran can design a custom neutral grounding system for your particular needs if a standard unit is not sufficient.  Typically all NGT systems share a common enclosure with separation between he NGT and resistor.