Adding two fans to a RAMPS 1.4 board Laser.

Current setup: RAMPS 1.4, Firmware 1.1.8, Full Graphics Display
Adding hard ware RRD Fan Extender

This extender works by using the 12V pins for power supply and plugging into the servo connector on the RAMPS board.



Pins 1 &2 are the 12V input from the RAMPS board.
Pins 3 & 4 12V fan connection
Pins 5 & 6 12V fan connection

I believe I can use FAN1_PIN and FAN2_PIN for this.

In the "pins_RAMPS.h' file I added the following to:

#if ENABLED(IS_REAMPS_EF
#define FAN_PIN RAMPS_D9_pIN
#define HEATER_BED_PIN REAMPS_D8_PIN
// I added:
#define FAN1_PIN 6
#define FAN2_PIN 11

Then I used M106 P1 128
M106 P2 128
to turn on the fans.

This setup only works for #define FAN1_PIN.
FAN2_PIN dose not work with M106P2 S128 or M42 P11 S128
So I'm guessing that for some reason I don't know about I can't use #define FAN2_PIN definition? Or what should the M106 or M42 command look like?
Any help would be appreciated.
Thank you

Edited 2 time(s). Last edit at 10/29/2018 08:09AM by kd6hq.

check you fan extender is actually wired to D6 and D11

I've seen variants still called the same thing but using other combinations of servo pins so any combination D11,D6,D5,D4

Also you wouldn't be able to use M42 on pin FAN2_PIN, If you look in pins.h there is a list of SENSITIVE_PINS (ie pins that you can't change with M42) and FAN2_PIN is listed.

so try //#define FAN2_PIN 11 and retry M42 P11 S128

Edited 2 time(s). Last edit at 11/10/2018 09:18AM by Dust.

Thank you Dust

It's working now.

However I will note that it is either full on or off.
Using M42 P11 S255 will turn it on but M42 P11 S254 will not.
For me that's fine, I using the fan to control air flow over heat sinks so full on is ok even thought I prefer 75%. Just seems to make things last longer but it is only a fan.

As far as pin 6 & 11 goes, they are the correct ones. This is one of the original boards before the clones came out. M106 XX S0-255 use to work on both fans but this was for older versions (1.1 or so) for the firmware. Somewhere along the line things changed.

Anyway thanks again.