The W7762A and B Controllers are Hydronic Controllers in the Excel 10 product line. They cover a wide range of control applications including radiators, induction units, and fan coil units with manual fan switching, and are suitable for either wall mounting or unit mounting. The controllers can operate as stand-alone units or networked using the standard Echelon LONWORKS bus. Interfaces are provided for a wide range of actuator types. Heating systems can be water or electric and cooling systems can be chilled water supply or compressors. Extensive timing and interlock features make the W7762 especially suitable for systems using electric heat and compressors.
The W7762A and B are LonMark compliant Hydronic Controllers in the Excel 10 family
product line. These controllers provide room temperature control using different heating
and cooling sequences. The controller is provided with default configuration settings from
the factory and is fully operable on installation. Using standard Echelon configuration
tools, the controller can be configured with job specific settings. A variety of optional
T7770 wall modules interface with the Hydronic Controllers and provide the following
options: setpoint adjustment, an occupancy bypass button and LED, and an E-Bus network
access jack. All wall include a space temperature sensor, however a remote C7068A return
air sensor can also be used.
| Ouput | Options |
| Heating | Floating, thermal, PWM, on/off, multi-stage electric |
| Cooling | Floating, thermal, PWM, on/off, multi-stage compressor |
Heat and cool sequences can be selected to be active or not active, giving a total of four different sequence options:
MODES OF OPERATION
The controller has the following modes of operation.
This is the normal operating condition for a room or zone when it is occupied. The controller can be switched into this mode by a network command, by the room occupancy sensor, or by a bypass button on the wall module.
The standby mode saves energy by reducing heating or cooling demand during periods where the room is temporarily unoccupied.
This mode is used for longer unoccupied periods, such as at night or during weekends and holidays.
If the controller is configured for window open detection, the controller automatically disables heat and cool control until the window is closed again. Frost protection remains active.
If the temperature drops below 46 Deg.F (8 Deg.C), the controller enables the heating circuit as frost protection.
When configured with an air flow detector, the controller protects equipment by disabling the system when the fan fails (for fan coil units with manual fan speed control).
The controller operates two-pipe units configured with a changeover input.
| Inputs | Function | Pin Number | Characteristics |
| Digital | Window/occupancy/changeover/air flow/condensation | 4 | Closed<=400 ohm, open>=10K ohm |
| Digital | Override | 7 | Closed<=400 ohm, open>=3.3k ohm |
| Analog | Temperature Sensor | 9 | 20K ohm NTC(25 deg C) |
| Analog | Setpoint adjustment | 8 | 10k Ohm |
| Outputs | |||
| Digital | Override LED | 6 | 0/5 Vdc (l<10mA) |
| Triac (2 pairs) | heat and cool | 14,15, 17, 18 | 24 Vac, 250 mA max continuous, 650 mA max surge(<=30 sec) |