# hotbed not hot

Posted by swilson100
 hotbed not hot August 02, 2013 03:39PM Registered: 10 years ago Posts: 8
I updated the marlin due to the z axis movement(solved)but now the hotbed does not heat.
The thermistor and bed work as I connected the bed to a 12v separate supply and it heated and the thermistor gave the temperature in Pronterface.The hot end works fine.
using sanguinololu reprap pro
I must has messed up the firmware some where any ideas.

===========================================================================
//=============================Thermal Settings ============================
//===========================================================================

// Set this if you want to define the constants in the thermistor circuit
// and work out temperatures algebraically - added by AB.

// See [en.wikipedia.org]

// BETA is the B value
// RS is the value of the series resistor in ohms
// R_INF is R0.exp(-BETA/T0), where R0 is the thermistor resistance at T0 (T0 is in kelvin)
// Normally T0 is 298.15K (25 C). If you write that expression in brackets in the #define the compiler
// should compute it for you (i.e. it won't need to be calculated at run time).

// If the A->D converter has a range of 0..1023 and the measured voltage is V (between 0 and 1023)
// then the thermistor resistance, R = V.RS/(1023 - V)
// and the temperature, T = BETA/ln(R/R_INF)
// To get degrees celsius (instead of kelvin) add -273.15 to T

// This DOES assume that all extruders use the same thermistor type.

#define ABS_ZERO -273.15

// RS 198-961
#define E_BETA 3974.0
#define E_RS SERIAL_R
#define E_NTC 100000.0
#define E_R_INF ( E_NTC*exp(-E_BETA/298.15) )

#ifdef REPRAPPRO_MENDEL

//// RS 484-0149; EPCOS B57550G103J standard 100k All Mendels and Thermistors shipped before 1/4/13
#define BED_BETA 3480.0
#define BED_RS SERIAL_R
#define BED_NTC 100000.0
#define BED_R_INF ( BED_NTC*exp(-BED_BETA/298.15) )

// Rapid 61-0446 ; Semitec 103GT-2 All Mendels and Thermistors shipped after 1/4/13
#define BED_BETA 4126.0
#define BED_RS SERIAL_R
#define BED_NTC 10000.0
#define BED_R_INF ( BED_NTC*exp(-BED_BETA/298.15) )

#endif

//#ifdef REPRAPPRO_HUXLEY
// VISHAY BC COMPONENTS - NTCS0603E3104FXT
//#define BED_BETA 4100.0
//#define BED_RS SERIAL_R
//#define BED_NTC 100000.0
//#define BED_R_INF ( BED_NTC*exp(-BED_BETA/298.15) )
//#endif

#define BED_USES_THERMISTOR
#define HEATER_0_USES_THERMISTOR
#define HEATER_1_USES_THERMISTOR
#//#define HEATER_2_USES_THERMISTOR

// Actual temperature must be close to target for this long before M109 returns success
#define TEMP_RESIDENCY_TIME 5 // (seconds)
#define TEMP_HYSTERESIS 5 // (C°) range of +/- temperatures considered "close" to the target one
#define TEMP_WINDOW 2 // (degC) Window around target to start the recidency timer x degC early.

// The minimal temperature defines the temperature below which the heater will not be enabled It is used
// to check that the wiring to the thermistor is not broken.
// Otherwise this would lead to the heater being powered on all the time.
#define HEATER_0_MINTEMP 1
#ifdef REPRAPPRO_MULTIMATERIALS
#define HEATER_1_MINTEMP 1
#define HEATER_2_MINTEMP 1
#endif
#define BED_MINTEMP 1

// When temperature exceeds max temp, your heater will be switched off.
// This feature exists to protect your hotend from overheating accidentally, but *NOT* from thermistor short/failure!
// You should use MINTEMP for thermistor short/failure protection.
#define HEATER_0_MAXTEMP 270
#ifdef REPRAPPRO_MULTIMATERIALS
#define HEATER_1_MAXTEMP 270
#define HEATER_2_MAXTEMP 270
#endif
#define BED_MAXTEMP 120

// PID settings:
// Comment the following line to disable PID and enable bang-bang.
#define PIDTEMP
#define PID_MAX 255 // limits current to nozzle; 255=full current
#define FULL_PID_BAND 150 // Full power is applied when pid_error[e] > FULL_PID_BAND
#ifdef PIDTEMP
//#define PID_DEBUG // Sends debug data to the serial port.
#define PID_INTEGRAL_DRIVE_MAX 125 //limit for the integral term
#define K1 0.95 //smoothing factor withing the PID
#define PID_dT 0.122 //sampling period of the PID

// RepRapPro Huxley + Mendel
#define DEFAULT_Kp 30.459
#define DEFAULT_Ki 3.078
#define DEFAULT_Kd 75.357

#endif // PIDTEMP

#ifndef DEVELOPING
//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
//can be software-disabled for whatever purposes by
#define PREVENT_DANGEROUS_EXTRUDE
#define EXTRUDE_MINTEMP 170
#define EXTRUDE_MAXLENGTH (200) //prevent extrusion of very large distances.
#else
#define BOGUS_TEMPERATURE_FAILSAFE_OVERRIDE
#endif[/size]
 Re: hotbed not hot August 03, 2013 12:22AM Registered: 13 years ago Posts: 1,797
what is your setup what printer is this for.

also why do you have 2 thermisters for extruder

#define HEATER_1_USES_THERMISTOR

should be commented out. it may be possible that the pins has this thermister set for the same pins as the bed. can you also list your pins.h file?
 Re: hotbed not hot August 03, 2013 05:15AM Registered: 10 years ago Posts: 8
thanks i'll try that this is the first time i've modified Marlin
 Re: hotbed not hot August 03, 2013 05:24AM Registered: 10 years ago Posts: 8
RepRapPro Mono Mendel/Sanguinololu 1.3a
 Re: hotbed not hot August 05, 2013 07:16AM Registered: 10 years ago Posts: 8
That didn't work so i've just wired the bed to the 12v supply/it heats up very quickly but you have to monitor the temp and switch it off and on manually
thanks anyway
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