Bluetooth環境センサーRS-BTEVS1からデータをNode-REDで可視化 の記事と類似した内容です。
使用機器
Bluetoothワットチェッカー RS-BTWATTCH2（ラトックシステム株式会社）
繋いだコンセントのON/OFF切り替えや、電圧・電流・電力を測定できるデバイスです。
BLEのレシーバーを使用して受信したデータをNode-REDで可視化していきます。
機器の接続
コンセントの間に入るよう接続します。再度のON/OFFボタンで給電の切り替えができます。
今回はPCの充電器を接続しています。
MACアドレスはON/OFFボタンの反対側に記載されています。
計測データの仕様をpdfから引用してきました。
ノードの作成
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まずは、BLE Beacon ScannarからRS-BTWATTCH2のMACアドレスでフィルターをかけ、データを絞り込みます。
本来は不要ですが、ここではRS-BTWATTCH2の仕様書通りに16進数の文字列等（生データ）を作成しています。
残りのノードでは、実際に各データを仕様書通りに読み分け、計算の必要な個所ではfunctionノードで処理をしています。
それぞれダッシュボード上に表示させています。
ダッシュボードでの表示
各データがこのように可視化されます。