このサンプルのフローでは、シミュレーターからの情報を閾値で判断してアクションへ繋げます。

Watson IoTレシピのシミュレータを使用します。
温度を取得し、閾値で判断します。
同じイベントを複数回検知するのを防ぐため、前回の発生から10秒以内であれば無視します。
イベントが検知されたらメールで通知します。

#センサータグからの値を閾値で判断するフロー

Node-REDのフローをコピーする方法を参照して、下記のフローをコピペします。

シミュレーターからの値を判断

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温湿度計シミュレーターを用意しますおよび温湿度計シミュレーターをフローに繋いでみるを参照して温湿度シミュレーターを用意し、デバイスIDを冒頭の青い「IBM IoT」ノードの「デバイスID」欄に指定します。
薄い緑色の「email」ノードにメール宛て先とメール発信のためのユーザーID+アプリパスワードを指定します。このメール発信にGmailを使用する場合にはユーザーID＋アプリパスワードはGmailヘルプ - アプリパスワードから取得します。
二カ所のオレンジ色の「htmlを返す」ノードを開き、<form method="get" action="http://<このIoTアプリの名前>.mybluemix.net/test10">のアプリ名部分を更新します。
ブラウザの新しいタブを開き、<IoTアプリ名>.bluemix.net/test7へアクセスすると下記のような画面が表示されます。