One of the largest destroyer of alternators in the marine world is when a cable comes loose, a fuse blows or an engine is electrically switched ‘off’ when the engine is running, all these things cause an alternator to be disconnected from the battery while running, this, in turn, causes a massive spike in the alternator which, in turn, can easily destroy the alternator regulator and any other advanced regulators in use, the resulting bills can easily run into the hundreds of pounds.  To avoid this, this simple device protects your alternator from that spike offering a simple safe emergency route for that spike to be discharged giving full protection to the alternator’s regulator with no back feed up the device. This unit is simple and easy to fit with no intrusion on the standard system. The unit does not carry the main current so only light wiring is required. This unit works in conjunction with any alternator or splitting device suitable for 12 or 24V alternators:   


Sterling Power

Manufacturer Part Number



H90 x W90 x D60mm




2 Years


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