Remote Voltage Sensing

1957 Chevrolet Belair

Remote voltage sensing is a must for good electrical system performance. It lets the voltage regulator make adjustments to the electrical system in order to maintain a system voltage of 14 volts. Remote Voltage Sensing is not a new idea. In fact many factory original systems have been using it for years. Even with the 10DN alternator and external voltage regulators back in the 1960s. The alternator voltage regulators constantly monitor the voltage level of the system. For most temperatures and conditions, the textbook battery voltage level when topping off a fully charged battery is about 14.2 volts with a 12-volt system.

The voltage regulator will adjust alternator output to maintain 14.2 volts at the battery under normal operating conditions. Therefore, most electrical system parts, lights, ignition, and accessories are designed for best performance when operating at about 14 volts. To deliver power to various parts of the electrical system, some of the wires will be long in length. Most often, the dash area with switches and fuse box is far from the alternator. And under the hood, the battery may be at the opposite side from alternator mounting, which will also require a long wire. Long lengths of wire will result in a voltage drop.

The key to good performance is to let the voltage regulator make adjustments to the voltage level sensed at the battery. Then other parts of the system will follow the voltage level maintained at the Battery. This is Remote Voltage Sensing. See diagram below of a typical 3 wire alternator with Remote Voltage Sensing! Tip: Never remove the connection at the battery when your car is running. You will do serious damage to your cars electrical system, as the alternator voltage regulator senses no battery voltage.

Remote Voltage Sensing - Delco SI diagram

1957 Chevrolet Convertible