Temperature wall module, 20,000-ohm Negative Temperature Coefficient (NTC). Non-linear family of direct-wired wall modules (TR21, TR22, TR23, and TR24) for use with Honeywell Excel 600, 500, 100, and 80 controllers; Excel 10 W7750, W7751A, W7752, and W7753 controllers; W7761 Controller; and Spyder Unitary Controllers. Models available with user selectable set point adjustment dials in Fahrenheit, Celsius and Relative scales. Models available with occupied/unoccupied override (bypass) with LED. Models available with three-position (auto/0/1) or five-position (auto/0/1/2/3 speed) fan switch. LONWORKS network jack on all models except TR21 and TR21-A models. Models available with on-board humidity sensor, humidity output: 0- 10-volt (DC), 0- 5-volt (DC), 4-20, Mixed Air (MA) selectable. Dimensions: 4-13/16 inch high x 3 inch wide x 7/8 inch deep (122mm high x 76.5mm wide x 22mm deep). Mount on standard 2 x 4 inch- junction box or on 60-mm diameter junction box. Underwriters Laboratories Inc. (UL)-approved. UL94 plastic enclosure. Operating humidity range (% Relative Humidity-RH): 5 to 95% RH, non-condensing. Set point temperature range: 55F to 85F (13C to 30C). Operating temperature range: 45F to 99F (7C to 37C). Color: white.