Are you certain these switches are normally closed ? The picture of the light circuit indicates they are normally open, without magnet.

You are correct. Almost all of the reed switches on Amazon universally have the NO/NC descriptions backwards. Even the guy who responded to you about his RV steps was mistaken as his application would require a normally closed switch (ie. door opening and removing the magnet would allow the current to flow). I think the big misunderstanding is these vendors (and some people) think the "normal" position is with a magnet adjacent the reed switch. It is not.

Brand	Gebildet
Model Number	DE453
Product Dimensions	14 x 11 x 1.1 cm; 50 g
Color	ブラック-なし
Power Source	バッテリー式
Voltage	100 Volts
Wattage	10 W
Are Batteries Included	No
Item Weight	50 g

Gebildet 3個 埋め込み式有線セキュリティウィンドウゲート 接触センサー アラーム 磁気リードスイッチ ブラック 磁気ドアセンサー 通常開く磁気スイッチ

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Gebildet 3個埋め込み式有線セキュリティウィンドウゲート接触センサーアラーム磁気リードスイッチブラック磁気ドアセンサー通常開く磁気スイッチ