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RTC3864 - Voltage Regulator – RB340 by Land Rover, LucasElectrical Part Land Rover Range Rover Series

RTC3864 - Voltage Regulator – RB340

- €137,40
€137,40
€137,40 - €137,40
€137,40
Genuine Part
Genuine: Original manufacturer part. This product is the original part designed and produced by the vehicle manufacturer.
Voltage Regulator for the dynamo charging circuit – the Lucas RB340 control box.

Wired between the C40 dynamo and the battery, the control box regulates the dynamo's output to match electrical load and battery state of charge. It houses the electromechanical regulator and cut-out contacts that prevent overcharging and stop the battery discharging back through the dynamo when the engine is stopped or turning slowly.
Vehicle Model Land Rover Series 1
Land Rover Series 2 and 3
Fitment Notes Fitment data limited — derived from web research, verify if uncertain
SERIES I/II/IIA — dynamo electrical system, Lucas RB340 (NCB133) voltage regulator for C40 dynamo generator
Alternative Codes
RTC3864

In stock 1 unit
1 · Gouda 0 · Drachten
Express delivery available

When will my order arrive?
  • Order before 15:00 (Mon–Fri): same-day dispatch for in-stock items.
  • UPS Express (order before 14:00): dispatched today, delivered tomorrow where available.
  • Netherlands / Belgium / Germany: 2–4 working days.
  • Other EU countries + UK: 4–8 working days.
  • Outside EU/UK: delivery times vary — contact us for an estimate.

Items may ship from multiple warehouses at no extra cost.

Job kits containing this part

This part is included in 0 job kit(s) below. Pick the kit that matches your vehicle and job, then add what you need.

Frequently asked questions

What is the RTC3864 voltage regulator and what does it do?
The RTC3864 is the Lucas RB340 control box for the dynamo charging circuit. Wired between the C40 dynamo and the battery, it regulates the dynamo's output to match electrical load and battery charge, and its cut-out contacts stop the battery discharging back through the dynamo at rest. Fits Land Rover Series 1, 2 and 3.
Does this regulator work with a dynamo or an alternator?
This regulator works with a dynamo, specifically the Lucas C40 dynamo, not an alternator. The RB340 control box suits the original dynamo charging system on the Land Rover Series 1, 2 and 3. Vehicles converted to an alternator use a different setup and won't need this control box.
Where is the RB340 control box mounted and is it a DIY fit?
The RB340 control box is typically mounted on the bulkhead or inner wing in the engine bay on Land Rover Series models. It usually fits at home with basic hand tools by transferring the wiring to the labelled terminals. Note the terminal positions before disconnecting so the new unit is wired correctly.