Extruder Fan Question

Hi everyone. I'm new here. I've searched the site trying to find an answer to my question and was not able to find anything. I have connected my extruder fan (the one that should always be ON when the extruder is heating) to the fan header as shown in the url shown below marked as "extruder Fan" I have another fan that blows on the object being printed to cool it which I have wired to D9. I control that fan's speed and such manually in Repetier host. The problem i'm having is that the extruder fan is ALWAYS on no matter if the extruder is on or not. I'm using Marlin 1.1.x and I assume that I need to set one of the following setting in the advanced tab but I can't figure out what PIN I should reference for that Extruder fan header. Any help would be great! Thanks!

#define E0_AUTO_FAN_PIN -1
#define E1_AUTO_FAN_PIN -1
#define E2_AUTO_FAN_PIN -1
#define E3_AUTO_FAN_PIN -1
#define E4_AUTO_FAN_PIN -1
#define EXTRUDER_AUTO_FAN_TEMPERATURE 50
#define EXTRUDER_AUTO_FAN_SPEED 255 // == full speed

Extruder Fan Header

You cant find it because it doesn't exist

The two pin connector is 12v and gnd. It is always on when power is on.

A standard ramps doesn't have enough mosfets for a controlled extruder fan.

You need to add another mosfet and connect it to the ramps on a free pin (one that can do PWM) most use D11 (on the servo plugs)

Google ramps fan extender...

Edited 2 time(s). Last edit at 08/24/2017 09:36PM by Dust.

There's nothing wrong with leaving the extruder fan on - what harm can it do?

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Waitaki 3D Printer

Its noisy, and better off turned off when not in use to reduce wear and tear and noise

But no, no harm per say.