@deckingman thanks for your reply, unfortunately the file doesn't exist.

why is it that when i turn the printer off then on again, the settings have been saved but the endstop doesnt work and the z axis moves up when homing z, my endstop switch is at the bottom.

@phaedrux the max rated current on the 2 extra extruders are 2amp, the original creality steppers are cr-10 42-34 and i couldn't find current ratings for it. when i move the axis it was easier to move it down,

Thanks Phaedrux, looks like those changes worked.
now i just have to connect the duex5 and hopefully start printing again.

thanks again for all your help.

damn, no idea what happened but it is having the same problem again

i finally fixed it by making these changes.

; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool on Thu Sep 27 2018 22:38:13 GMT+1000 (Australian Eastern Standard Time)
;G91 ; relative positioning
;G1 Z5 F6000 S2 ; lift Z relative to current position
;G1 S1 Z-455 F1800 ; move Z down until the endstop is triggered
;G92 Z0 ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
;G91 ; relative positioning
;G1 S2 Z5 F100 ; lift Z relative to current position
;G90 ; absolute positioning

G91 ; relative mode
G1 S1 Z250 F300 ; move Z towards the switch until it triggers
G1 Z-5 F100 S2 ; move Z back 5mm
G1 S1 Z10 F100 ; move Z slowly towards the switch until it triggers
G90 ; back to absolute mode

currently i only have the duet connected, ill be connecting the duex5 once i get this working.

thanks for getting back to me so quick,
no probe
ive had a quick read of the link before but there must be something im missing.
here are the settings i have:

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool on Thu Sep 27 2018 22:38:13 GMT+1000 (Australian Eastern Standard Time)
G91 ; relative positioning
G1 Z5 F6000 S2 ; lift Z relative to current position
G1 S1 X-455 Y455 F1800 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 X5 Y-5 F6000 ; go back a few mm
G1 S1 X-455 Y455 F360 ; move slowly to X and Y axis endstops once more (second pass)
G1 S1 Z-455 F1800 ; move Z down stopping at the endstop
G90 ; absolute positioning
G92 Z0 ; set Z to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
G91 ; relative positioning
G1 S2 Z5 F100 ; lift Z relative to current position
G90 ; absolute positioning

; homex.g
; called to home the X axis
;
; generated by RepRapFirmware Configuration Tool on Thu Sep 27 2018 22:38:13 GMT+1000 (Australian Eastern Standard Time)
G91 ; relative positioning
G1 Z5 F6000 S2 ; lift Z relative to current position
G1 S1 X-455 F1800 ; move quickly to X axis endstop and stop there (first pass)
G1 X5 F6000 ; go back a few mm
G1 S1 X-455 F360 ; move slowly to X axis endstop once more (second pass)
G1 Z-5 F6000 S2 ; lower Z again
G90 ; absolute positioning

; homey.g
; called to home the Y axis
;
; generated by RepRapFirmware Configuration Tool on Thu Sep 27 2018 22:38:13 GMT+1000 (Australian Eastern Standard Time)
G91 ; relative positioning
G1 Z5 F6000 S2 ; lift Z relative to current position
G1 S1 Y455 F1800 ; move quickly to Y axis endstop and stop there (first pass)
G1 Y-5 F6000 ; go back a few mm
G1 S1 Y455 F360 ; move slowly to Y axis endstop once more (second pass)
G1 Z-5 F6000 S2 ; lower Z again
G90 ; absolute positioning

; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool on Thu Sep 27 2018 22:38:13 GMT+1000 (Australian Eastern Standard Time)
G91 ; relative positioning
G1 Z5 F6000 S2 ; lift Z relative to current position
G1 S1 Z-455 F1800 ; move Z down until the endstop is triggered
G92 Z0 ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
G91 ; relative positioning
G1 S2 Z5 F100 ; lift Z relative to current position
G90 ; absolute positioning

been trying to upgrade my cr-10s with Duet 2 WIFI + Duet 5, i got most of it working(eventually) except for the Z endstop.
i've got both drive 2 plugs populated(2 z steppers) and z endstop plugged where it should be, when i try and home the z axis, the endstop is hit but the stepper keeps going until i switch the printer off.
the endstops LEDs are lit when they are not pressed(guessing active high), when i try home the z axis, it makes a funny sound for few seconds then drops past the switch. this is my config.g, please can someone help? ive been working on this upgrade for over a week. GRRRR

General preferences
G90 ; Send absolute coordinates...
M83 ; ...but relative extruder moves

; Network
M550 PMy printer ; Set machine name
M552 S1 ; Enable network
M587 S"*" P"" ; Configure access point. You can delete this line once connected
M586 P0 S1 ; Enable HTTP
M586 P1 S0 ; Disable FTP
M586 P2 S0 ; Disable Telnet

; Drives
M569 P0 S0 ; Drive 0 goes backwards
M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S0 ; Drive 2 goes forwards
M569 P3 S0 ; Drive 3 goes forwards
M569 P4 S1 ; Drive 4 goes forwards
M569 P5 S1 ; Drive 5 goes forwards
M350 X16 Y16 Z16 E16:16:16 I1 ; Configure microstepping with interpolation
M92 X80 Y80 Z4000 E420:420:420 ; Set steps per mm
M566 X900 Y900 Z12 E72000:72000:72000 ; Set maximum instantaneous speed changes (mm/min)
M203 X1200000 Y1200000 Z1200000 E216000:216000:216000 ; Set maximum speeds (mm/min)
M201 X3000 Y3000 Z3000 E1000:1000:1000 ; Set accelerations (mm/s^2)
M906 X1000 Y1000 Z1500 E1000:1000:1000 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

; Axis Limits
M208 X0 Y0 Z0 S1 ; Set axis minima
M208 X450 Y450 Z450 S0 ; Set axis maxima

; Endstops
M574 X1 Y2 Z1 S1 ; Set active high endstops

; Z-Probe
M558 P5 H5 F120 T6000 ; Set Z probe type to switch and the dive height + speeds
G31 P500 X0 Y0 Z2.5 ; Set Z probe trigger value, offset and trigger height
M557 X15:435 Y15:435 S20 ; Define mesh grid

; Heaters
M307 H0 B0 S1.00 ; Disable bang-bang mode for the bed heater and set PWM limit
M305 P0 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 0
M143 H0 S120 ; Set temperature limit for heater 0 to 120C
M305 P1 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 1
M143 H1 S280 ; Set temperature limit for heater 1 to 280C

; Fans
M106 P0 S0.3 I0 F500 H-1 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off
M106 P1 S1 I0 F500 H1 T45 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on
M106 P2 S1 I0 F500 H1 T45 ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned on

; Tools
M563 P0 D0 H1 ; Define tool 0
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C
M563 P1 D1 H ; Define tool 1
G10 P1 X0 Y0 Z0 ; Set tool 1 axis offsets
G10 P1 R0 S0 ; Set initial tool 1 active and standby temperatures to 0C
M563 P2 D2 H ; Define tool 2
G10 P2 X0 Y0 Z0 ; Set tool 2 axis offsets
G10 P2 R0 S0 ; Set initial tool 2 active and standby temperatures to 0C

; Automatic power saving
M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000" ; Set voltage thresholds and actions to run on power loss

; Custom settings are not configured

; Miscellaneous
T0 ; Select first tool

Thank you