Regulators for Generators

Regulators for DC alternators

These regulators are available for original applications and restorations as mechanical regulators with built-in reverse current relay. They are all protected against vibrations byrubber mounts. Therefore, a ground cable is necessary for all mechanical regulators to function properly. Model-specific mounts are also available for original applications.

Maintenance-free regulators rely on electronic components. Instead of reverse current relays, diodes are installed. Electronic regulators - made by Cycle Electric, USA and Samwel, NL - are available for mounting directly on the end of the alternator or for separate mounting in a suitable location. For older engine cases up to 1957 that still have the aluminum socket for the reverse current relay, there are relay style regulators that fit on this socket. On these engine cases, these regulators allow conversion from three-carbon to two-carbon alternator while providing an answer to the question "Where to put the regulator?". Electronic regulators are largely vibration resistant, and the ground goes through the housing. Therefore, care must be taken to ensure good grounding when mounting. Poor ground connection will lead to component failure.

Can regulators be repaired?

Theoretically, yes. In practice, however, regulators are replaced if they are defective. The repair costs can easily exceed the cost of a new part. Repairs are therefore only worthwhile for unobtainable original parts.

How do defects in regulators show up?

In practice, one will suspect a defect at the regulator,

• if the voltage at the battery does not rise above the idle voltage of the battery when the engine is running, or
• if the voltage rises far above 15 V (for 12 V systems) or 7.5 V (for 6 V systems) when the engine is running.

Often you only notice these faults when driving, when the engine starts to stutter or the headlight bulb constantly fails at higher speed. Regular checks every few weeks in your local garage are therefore adviced.

An acid battery that constantly needs to be topped up with distilled water, or a maintenance-free battery that does not keep the voltage for more than a few days, must be checked for defects. To be sure that the regulator is not the real cause of the problems, it must also be checked.