<p>It does work, but you need to reset EEPROM memory once updating the firmware, if you had it enabled, so the values are transferred into the EEPROM and subsequently used.</p>

<p>To reset  EEPROM, send the following command in your 3d printer terminal.</p>

<p><code>M502</code></p>

<p>Then, save the firmware default settings</p>

<p><code>M500</code></p>

CC BY-SA 4.0
2019-11-22T01:55:04.513Z
2019-11-22T22:24:48.160Z
2019-11-22T22:24:48.160Z
K Mmmm
<p>Is anyone using hysteresis with their chamber in Marlin?</p>

<p>I have read bang-bang with hysteresis is possible when using a bed heater. I would like to do that for chamber heating. I have some lamps that can't keep flicking on and off so rapidly around a setpoint - this causes the bulb to die out faster and the noise is annoying.</p>

<p>Steps to Reproduce:</p>

<ol>
<li>Start with fresh Marlin Firmware bugfix 2.0</li>
<li>Enable chamber temperature in Configuration.h (<code>TEMP_CHAMBER_PIN 1</code>)</li>
<li>Set chamber hysteresis value to 2 in Confgiuration_adv.h (<code>#define TEMP_CHAMBER_HYSTERESIS     2</code>). Enable <code>#define CHAMBER_LIMIT_SWITCHING</code> in Configuration_adv.h. Decide on pin to use for your heater, if necessary</li>
</ol>

<p>Expected behavior: I would like, when I set my chamber to 30&nbsp;&deg;C, the chamber lamps to come on until 32&nbsp;&deg;C, and to stay off until 28&nbsp;&deg;C.</p>

<p>Actual behavior: chamber heater lamps flick on and off at 30&nbsp;&deg;C (29.9 - on, 30.1 - off).</p>

<marlin><heat-management><chamber>
Chamber heating using hysteresis in Marlin
K Mmmm
# Chamber heating using hysteresis in Marlin

(Asked by: username_0 on 2019-11-22)

Is anyone using hysteresis with their chamber in Marlin?

I have read bang-bang with hysteresis is possible when using a bed heater. I would like to do that for chamber heating. I have some lamps that can't keep flicking on and off so rapidly around a setpoint - this causes the bulb to die out faster and the noise is annoying.

Steps to Reproduce:

1. Start with fresh Marlin Firmware bugfix 2.0
2. Enable chamber temperature in Configuration.h (`TEMP_CHAMBER_PIN 1`)
3. Set chamber hysteresis value to 2 in Confgiuration\_adv.h (`#define TEMP_CHAMBER_HYSTERESIS 2`). Enable `#define CHAMBER_LIMIT_SWITCHING` in Configuration\_adv.h. Decide on pin to use for your heater, if necessary

Expected behavior: I would like, when I set my chamber to 30 °C, the chamber lamps to come on until 32 °C, and to stay off until 28 °C.

Actual behavior: chamber heater lamps flick on and off at 30 °C (29.9 - on, 30.1 - off).

**Tags:** marlin, heat-management, chamber


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## 1 answers

### Answer by username_0 on 2019-11-22. Score: 3 | Accepted answer

It does work, but you need to reset EEPROM memory once updating the firmware, if you had it enabled, so the values are transferred into the EEPROM and subsequently used.

To reset EEPROM, send the following command in your 3d printer terminal.

`M502`

Then, save the firmware default settings

`M500`


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