Electric Fan Voltage Drop

Grab a volt meter and measure the voltage at the alternator.

Electric fan voltage drop. It is recommended that the voltage drop should be less than 5 under the fully loaded condition. Might help you a lot with the voltages your are seeing. The voltage drop test is a dynamic test intended for use mainly with high current draw systems such as the starting system charging system or items such as a heater fan electric fuel pump or. Voltage would start off at 14 0 and drop down to 12 5 with both fans on entropy fans are big power hogs and everything else on.

You may double the fan belt or use a serpentine belt so it won t slip. When electric fan installs don t perform as expected the problems are often traceable to under wiring and or poor splices and grounds. If does not drop then run a heavyer gauge wire between the alternator and junction terminal. I have never had any problem with the battery going dead or any long term charging issues.

Basic voltage drop law v drop ir. I switched to a 170 amp holley alternator along with a new drive setup on my ls and added a 4 awg feed wire. Put a diode in series at the alternator on the excite trigger wire. When the air is on and the auxiliary electric fan kicks in my voltage drops from 14 2 down to about 12 5 13.

The actual voltage drop can vary depend on the condition of the wire the conduit being used the temperature the connector the frequency etc. What the diode does is drops the voltage by about.