RAMPS 1.4 heated bed issues

Ok, so I've been running one of our H-1's with a ramps setup off and on for a while now. Putting on my heated bed now. Problem I'm having is, I now have no fan control, and I can set bed temp, and turn it on, but cannot shut it off? Seems like it waits a few seconds after turning it on, then the LED comes on and I have 12v on D8, but I cannot shut it off?

// ############# Heated bed configuration ########################

/** \brief Switches fast between config for heated bed and non heated bed. Default setting is autodetect
assuming only 2 heater outputs are available. */
//#if HEATER_1_PIN>-1 && NUM_EXTRUDER==1
//#define HAVE_HEATED_BED true
//#else
//#define HAVE_HEATED_BED false
//#endif
#define HAVE_HEATED_BED true // Override autodetected value

#if HAVE_HEATED_BED==true
// Select type of your heated bed. It's the same as for EXT0_TEMPSENSOR_TYPE
// set to 0 if you don't have a heated bed
#define HEATED_BED_SENSOR_TYPE 99
/** Index of analog sensor to read temperature of heated bed.
THIS IS NOT A PIN NUMBER - IT'S A REFERENCE TO A TABLE WITH PIN NUMBERS!!!
Look at ANALOG_INPUT_CHANNELS for the position
or to add the Arduino pin id there. */
#define HEATED_BED_SENSOR_PIN 1
/** \brief Pin to enable heater for bed. */
#define HEATED_BED_HEATER_PIN HEATER_1_PIN
// How often the temperature of the heated bed is set (msec)
#define HEATED_BED_SET_INTERVAL 5000
//#else
//#define HEATED_BED_SENSOR_TYPE 0
//#define HEATED_BED_SENSOR_PIN -1
//#define HEATED_BED_HEATER_PIN -1
//#endif

Edited 1 time(s). Last edit at 05/30/2012 01:16PM by johnoly99.

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John "Oly"
SeeMeCNC.com

Setting the temperature to zero?

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Hey traum, yep, tried sending manually M140 S0 as well as clicking heater off icon. Nothing turns it off once its on. It only comes on when a m140 call is sent, but it will not go off unless i reset the board?

Try using the fan PWM output for the heated bed, you'll have to change pins.h.
If that works it's likely an issue with the RAMPS or Arduino boards, it's going to be hard to nail down without replacements.

Ill pop it on another MEGA and see if it changes, then ill know its in the ramps or mega board. What though i wonder would cause yhe mosfet to latch on and not off?

My best guess is the issue is with the PWM generator, that it's just switching high and not pulsing.

Quote

yep, tried sending manually M140 S0 as well as clicking heater off icon. Nothing turns it off once its on.

You have a funny firmware there

I see no reason why it should be a hardware problem. Pins can be dead (by mistreating them badly), but then they don't turn on either.

Wether PWM works or not can be seen on the LED near the MOSFET (in the hope there is such an LED). Lower PWM values make the LED less bright.

But then, you set the temperature, not the PWM value directly. Is it possible your firmware ignores temperature changes until the previoulsy commanded one is reached?

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Thanks traumflug, and yes, it's a bit goofy as I don't use endstops, and my pins are all re routed from when I was trying some other stuff. But, alas I've fixed it, sort of. I had to define a seperate thermistor table for the heated bed to match my thermistor, then I started getting better temp readings. The sort of in my statement is, Once it reaches the programmed temp, it will shut off, and on with both Gcode sends and the power button. What's weird is that it only does this after it hits the set temp for the first time the boards powered up. Kinda dangerous if you're just setting something up no? I mean, it works after it reaches temp, but wont turn off until it hits whatever temp is first sent to it, even if you manually send a lower temp. I'm sure there's a fix in the firware for that, and I'll be waiting. Until then, at least it works now, and we'll see what others say?

There is an issue in repetier where it insists on completing commands in its internal queue. EStop and Kill Job just stop it sending more commands. There have been several times I's wished the EStop had worked.
If it's an M190 in the queue your stuck waiting for the bed to reach temperature, or pressing the reset button.
If your sending the Set temperature and wait command (M190?) it will insist on reaching the initially set temperature, you should be able to send the set temperature but don't wait command (M140) as many times as you like, I commonly push the Heat On button on the print panel then change the temperature.