...e is provided with the ES2-HB-N/-THB-N. Always attach the Humidity Sensor Module when using the ES2-HB/-THB. Approximately 5.5 VDC will be output for the humidity output if the Module is not ...https://www.ia.omron.com/data_pdf/cat/es2-hb-n_es2-thb-n_h230-e1_2_1_csm1062563.pdf