Summary of the content on the page No. 1
T7984 A,B,C Electronic Modulating Control
Thermostats
PRODUCT DATA
FEATURES
• PI (proportional and integral) control action provides
accurate, stable room temperature control.
• T7984 models are used with Series 70 direct-coupled
damper actuators such as ML7161 or ML7984, or with
valve actuators such as ML7285, ML7421, VC7930 or
M7410.
• All models feature user-friendly set point knob.
• All models feature output status LEDs for installer
check-out.
• Locking cover and range stops
Summary of the content on the page No. 2
T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS SPECIFICATIONS IMPORTANT The specifications given in this publication do not include normal manufacturing tolerances. Therefore, this unit may not exactly match the listed specifications. Also, this product is tested and calibrated under closely controlled conditions, and some minor differences in performance can be expected if those conditions are changed. MODELS: T7984A,B,C, 2 to 10 Vdc analog output Table 1. Model Specifications Co
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T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS Table 2. Option Settings CAUTION Disconnect power supply to prevent electrical T7984 Model shock or equipment damage. Parameter Selection A B C Wiring Reheat Time Fast (7.5 min.); or Normal • Typical wiring connections are shown in Fig.2 to Fig.7. Wiring Constant (15 min.) connections may be made to the screw terminal block with 2- Zero Energy 3°F (1.5°C); or 5°F (3°C) • • 18AWG or 1-14AWG, solid or stranded copper wires. Connect
Summary of the content on the page No. 4
T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS T7984A Output 1 analog Output 2 Mode input Changeover input Day/Night Remote sensor 75°F setpoint 2œ10V on/off jumper for Out 1 mode (NSB) option limit Cooling and/or X X heating WIRING To install a remote duct or room temperature sensor, adust DIP the screw terminals and wire as shown. switch S6 to 0 = off and wire as shown. (If sensor is used, wire 1changeover sensor per To reverse operation of output 1 to heating, install the the
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T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS T7984B Output 1 analog Output 2 Mode input Changeover input Day/Night Remote sensor 75°F setpoint 2œ10V on/off jumper for Out 1 mode (NSB) option limit Mode A (Jumper out) Cooling Heating X X X Mode B (Jumper in) Heating Cooling WIRING To install a remote duct or room temperature sensor, adjust * To enable mode B of operation, install a jumper across the DIP switch S6 to 0 = off and wire as shown. screw terminals and wire as shown
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T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS T7984C Output 1 analog Output 2 Mode input Changeover input Day/Night Remote sensor 75°F setpoint 2œ10V analog 2œ10V jumper for Out 1 mode (NSB) option limit Cooling and Heating only X X X X Heating WIRING To install a remote duct or room temperature sensor, adust DIP the screw terminals and wire as shown. switch S6 to 0 = off and wire as shown. (If sensor is used, wire 1changeover sensor per To reverse operation of output 1 to heat
Summary of the content on the page No. 7
T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS Output 1, Modulating Analog Output 2 to Zero Energy Band (T7984B & C) Thermostats which have cooling and heating outputs (T7984B 10Vdc (T7984 All) & C) have 2 distinct setpoints, one for heating the other for Main output of the thermostat. On the T7984 series that output cooling (see the control curves section for each model). When is modulating PI analog (2 to 10 Vdc). That signal uses a the room temperature is between these to setpo
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T7984 A,B,C ELECTRONIC MODULATING CONTROL THERMOSTATS Output 2 On/Off (T7984B only) CHECKOUT A 24 Vac on/off output which is normally used to control terminal reheat in a zoned system. Example: electric base board relay, Service LED electric duct heater relay, perimeter on/off 24 Vac valve, etc. All thermostats have internal service LED & a system status This output can also be used for cooling applications with the Led on the cover. The internal service LED are colored lights mode jum
