DIY RAMPS PROBLEM HEATER BED PRONTERFACE

HI

I'm developing my own printer, I'm connecting thermistors 100kohm and mosfets. But when I start to heat the heater, also appears in pronterface I'm warming the bed.
heat = 50 °C and bed = off but temperature graph bed different of off

i´m ussing ARDUINO and RAMPS schematic with marlin firmware

Why?


thanks

Edited 1 time(s). Last edit at 09/04/2014 01:55AM by YIBRIL LAGAIEL.

Writing all upper case is considered to be shouting. I don't like people shouting at me.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

At a guess d8 and d9 are shorted together somewhere (or what ever pins your using)

remove the hot ends and heated bed

Stick a multimeter into D9 and turn on the hot end, do you read 12v?
now check D8 is it also 12v?

If so you probably have a short between d8 and d9 somewhere...

unplug your ramps (while it all off) and check Resistance between the d8 and d9 ramps pins that plug into the mega connector, there shouldn’t be any connection
See pins labelled 8 and 9, top row, end of first connector on the left (image)
If the ramps look ok, check the same pin connectors on the mega

Could also be at the mosfet end. if your making your own board. Don't connect the back of the mosfets together electrically on the heat sink.

Edited 3 time(s). Last edit at 09/05/2014 06:33AM by Dust.