Lovato RTB035 is a Type B toroidal current transformer with a 35 mm internal diameter designed for residual-current sensing with compatible Lovato Type B earth leakage relays.
£215.65
The Lovato RTB035 is a Type B toroidal current transformer designed for use with compatible Lovato earth leakage relays. It provides residual-current sensing for electrical protection systems where Type B detection characteristics are required, making it an important component in earth leakage monitoring and protection applications.
Featuring a 35 mm internal diameter, the RTB035 allows the conductors of the monitored circuit to pass through the toroidal opening. The phases and neutral, when present, are routed through the transformer so that residual current can be detected by the connected compatible earth leakage relay, while the protective earth conductor must remain outside the toroid.
The RTB035 supports Type B residual operation and is suitable for systems requiring a 30 mA earth leakage relay threshold when used with compatible Lovato Type B relay equipment. Its compact dimensions, 322 g weight and conformity with IEC/EN/BS 60947-2 make it a practical sensing component for professional industrial and commercial electrical protection systems.
A toroidal current transformer used with an earth leakage relay monitors the vector sum of the currents flowing through the conductors passing through its aperture. Under normal operating conditions these currents balance; when leakage to earth occurs, an imbalance is detected by the toroid and transmitted to the associated earth leakage relay for evaluation and protective action.
For correct operation of the RTB035, the conductors of the circuit being monitored must pass through the toroidal transformer, including all phases and the neutral conductor when present. The protective earth conductor must not pass through the toroid. Lovato also recommends keeping the toroid-to-relay connection away from power cables and minimising the connection distance to reduce susceptibility to electromagnetic interference.
| Manufacturer | Lovato Electric |
|---|---|
| Series | RTB |
| Model | RTB035 |
| Product type | Toroidal current transformer |
| Application | Earth leakage relay systems |
| Residual operation characteristic | Type B |
| Toroidal transformer diameter | 35 mm (1.38 in) |
| Suitable residual-current threshold | 30 mA with compatible relay equipment |
| Overall dimension A | 100 mm |
| Overall dimension B | 110 mm |
| Dimension C | 60 mm |
| Internal diameter D | 35 mm |
| Dimension E | 47 mm |
| Dimension F | 70 mm |
| Dimension G | 63 mm |
| Dimension H | 50 mm |
| Conformity | IEC/EN/BS 60947-2 |
| ETIM 8.0 classification | EC002048 – Current transformer |
| Weight | 322 g |
| Quantity per package | 1 |
| Package dimensions | 113 × 72 × 120 mm |
| EAN | 8013975323847 |
| HS code | 85043121 |
The RTB035 is a Type B toroidal current transformer designed for residual-current sensing when used with compatible Lovato earth leakage relay systems.
The Lovato RTB035 has an internal toroidal diameter of 35 mm (1.38 in).
No. The RTB035 is the external toroidal current transformer that senses residual current and is intended to operate with a compatible Type B earth leakage relay.
Yes. Lovato specifies the RTB035 as suitable for a 30 mA threshold when used with compatible Type B earth leakage relay equipment.
All live conductors belonging to the monitored circuit should pass through the toroid, including the phases and neutral when present. The protective earth conductor must not pass through the transformer.
The RTB035 is specifically designed for Type B residual-current operation when used as part of a compatible Lovato Type B earth leakage protection system.
The Lovato RTB035 is specified as conforming to IEC/EN/BS 60947-2.
Lovato Electric earth leakage monitoring components provide practical solutions for industrial and commercial electrical installations where dependable residual-current detection, compatibility with dedicated protection relays and straightforward integration into electrical protection systems are required.
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