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TR21 20 K ohm NTC non­linear Temperature Wall Module

NECC sells Honeywell TR71 20K ohm NTC non-linear Temperature Wall Module


The TR21, TR22, TR23, and TR24 are a family of direct wired wall modules 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 setpoint adjustment dials in Fahrenheit, Celsius and Relative Scales

Models available with occupied/unoccupied override (bypass) with LED

Models available with 3­position (auto/0/1) or 5­position (auto/0/1/2/3 speed) fan switch

LONWORKS network jack on all models except the TR21 and TR21­A models

Models available with on board humidity sensor, humidity output: 0­10Vdc, 0­5 Vdc, 4­20ma selectable

Product Specifications

Application.. Wall Module Networked Sensor

Dimensions (in.).. 4 13/16 in. high x 3 in. wide x 7/8 in. deep

Dimensions (mm).. 122mm high x 76.5 mm wide x 22 mm deep

Used With.. Spyder, Excel 600, 500, 100, 80 and Excel 10, 15 Series

Controllers.. Also used with the T7350 and TB8220 Thermostats

Mounting.. Mounted on a standard 2 x 4 inch junction box or on a 60 mm diameter junction box.

Operating Humidity Range (% RH).. 5 to 95% RH, non­condensing

Sensor.. 20 K ohm NTC non­linear

Setpoint Temperature Range (C).. 13 C to 30 C

Setpoint Temperature Range (F).. 55 F to 85 F

Operating Temperature Range (F).. 45 F to 99 F

Operating Temperature Range (C).. 7 C to 37 C

Tr21 (TR21.pdf, 1,182 Kb) [Download]

Substitutes or Accessories