Last week we discussed the use of automatic electrical appliances on Shabbat, and concluded that before Shabbat begins it is permitted to program a timer to turn on and off the lights on Shabbat .
The same principle would apply to a sprinkler system. It is permitted to program it in a way that it will be automatically activated on Shabbat. Again, it is forbidden for a 'person' to perform a melakha (any activity forbidden by Tora on Shabbat is called melakha), but when that melakha is done by itself, there is no prohibition.
Same principle would apply to a Shabbat automatic elevator. I can use it on Shabbat because I'm not activating it on Shabbat.
To clarify this principle of 'activation', let me compare it with a few more complicated cases.
1. A microphone. Even when a microphone is turned on from before Shabbat, there is a principle of activation by the speaker who 'activates' the conversion process: sound (acoustical waves )> electrical waves >amplified sound. Not good for Shabbat!
2. 'Motion activated lights', do not belong into the same category of lights turned on and off by a timer. Because, while the timer will turn on the lights activated by its internal clock or by an electrical optical eye (there is no human 'activation' of any sort) the motion lights will be activated by 'me', by my motion. Not good for Shabbat!
Candle Lighting in NY: 4:22 PMShabbat Ends in NY: 5:29
WATCH AND LEARN: 'Burning Bridges', by Charlie Harary.
Rabbi Yosef Bitton. YMJC | 130 Steamboat Rd. | Great Neck | NY | 11024