NJREC 123 kV wall bushings carry a conductor through a grounded wall or partition while insulating it from the structure. This air-to-air product is intended for 110 kV or 115 kV nominal power systems and has an equipment highest voltage (Um) of 123 kV in the IEC 60137:2017 series. The maximum rated current shown for this voltage class is 4000 A.
| Parameter | Unit | IEC 60137:2017 123 kV |
|---|---|---|
| Highest voltage for equipment Um | kV | 123 |
| Rated frequency | Hz | 50/60 |
| Dry power frequency withstand voltage, 1 minute | kV | 230 |
| Lightning impulse withstand voltage (BIL) | kV | 550 |
| Switching impulse withstand voltage (SIL) | kV | – |
| Maximum rated current | A | 4000 |
| Temperature range | °C | Down to −60 °C and up to +55 °C available on request |
A 123 kV wall bushing can carry a high-voltage conductor through a substation control-room partition or the wall of a GIS building. Depending on the site layout, it can connect indoor-to-indoor, indoor-to-outdoor or outdoor-to-outdoor air-side circuits.
Where the main transformer's high-voltage outgoing conductor crosses a fire wall to an air-insulated switchyard, a wall bushing provides insulation at the wall opening. An FCRG1-LZ configuration with an integrated current transformer (CT) may be specified for this arrangement when the project requires it.
The same air-to-air wall passage can serve 110 kV areas in power plant step-up stations, renewable-energy collector stations, captive substations and large industrial facilities. The final housing and mounting arrangement depend on which sides are exposed outdoors.
NJREC offers a 123 kV IEC wall bushing option for air-to-air wall passages, with voltage-specific current and insulation ratings. The selected configuration can be reviewed against the wall thickness, mounting flange, conductor terminals and installation environment.
For a replacement, NJREC can compare the original unit's dimensional drawing and connection details with the proposed bushing to check fit and electrical compatibility. This wall-through product does not replace an FBRG transformer tank bushing, which crosses the transformer tank boundary.
The IEC equipment highest voltage (Um) is 123 kV, suitable for a 110 kV or 115 kV nominal system. The maximum rated current shown in the 123 kV column is 4000 A.
The 1-minute dry power frequency withstand voltage is 230 kV, and the lightning impulse withstand voltage (BIL) is 550 kV.
Yes, when the high-voltage conductor crosses the fire wall with air on both sides. A configuration with an integrated CT can be considered where the project requires current measurement; it is separate from the transformer tank bushing.
No. A 132 kV nominal system normally requires the corresponding 145 kV equipment highest voltage class, with different insulation requirements.
Check the opening size, wall thickness, flange, terminals and conductor projection on both sides. An existing dimensional drawing helps NJREC review interchangeability.
