Sabbath mode

Sabbath mode, also known as Shabbos mode (Ashkenazi pronunciation) or Shabbat mode, is a feature in many modern home appliances, including ovens and refrigerators, which is intended to allow the appliances to be used (subject to various constraints) by Shabbat-observant Jews on the Shabbat and Jewish holidays. The mode usually overrides the usual, everyday operation of the electrical appliance and makes the operation of the appliance comply with the rules of Halakha (Jewish law).

Halakha forbids Jews from doing creative work on the Shabbat. Observant Jews interpret this to include various activities including making a fire, preparing food, or even closing a switch or pressing an electronic button. A range of technology solutions have been created for those who need to use electronic (or electronic-controlled) devices on the Shabbat, including a special "sabbath mode" for otherwise standard appliances.

While according to Halakha, raw food may not be cooked on the Shabbat, food that was already cooked beforehand may be kept warm until mealtime. On some holidays, food may be cooked, but turning the heat on is prohibited. In the past, the problem could be solved simply by lighting a stove or oven before the day began, and using its heat over the course of the day. In recent decades, however, appliance manufacturers have instituted a fire prevention safety feature that automatically shuts off the heat after a number of hours. This renders the appliance useless for those who observe these religious laws.

When an oven is in Shabbat mode, the standard six- or twelve-hour automatic shutoff is overridden, and all lights and displays (for example, a light that might go on when the door is opened) are disabled.

In more recently designed ovens, Shabbat mode will often feature the ability to adjust the temperature of the oven without any feedback to the operator of the oven. According to the prevailing Orthodox opinion and the minority Conservative view, this is not relevant to the Shabbat, but is useful on some holidays, when adjusting the heat is allowed, but changing a digital readout on the control panel is not.

With some Shabbat mode ovens that are controlled using a keypad to set the temperature, there is a random delay triggered after a button is pressed before the temperature change takes place.

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Wikipedia