Honeywell W7752D specifications Bypass, Energy-Saving Features

EXCEL 10 FCU CONTROLLER LNS PLUG-INS USER GUIDE

Bypass

Bypass Mode

When the Excel 10 FCU Controller is in the "unoccupied" mode, the Excel 10 wall module's bypass push-button may be used to force the Excel 10 FCU Controller into the "occupied" mode. The Excel 10 FCU Controller can also be forced into the "occupied" mode by means of a LONWORKS network command (when nviManOccCmd is set to OC_BYPASS). The controller will then remain in "bypass" mode until:

1.The bypass timer has timed out, or

2.The user again presses the Excel 10 wall module's bypass push-button, thus cancelling the "bypass" mode, or

3.The occupancy schedule (nviTodEvent) switches the mode to "occupied".

4.nviManOccCmd is set to OC_NUL.

The Excel 10 wall module indicates the current bypass mode status (see Excel 10 wall module literature for further information).

Bypass Timer

When the "bypass" mode has been activated, the bypass timer is set to BypTime (default of 180 minutes), at the end of which the mode will revert to its original state (see Excel 10 wall module literature for further information).

Continuous "Unoccupied" Mode

The continuous "unoccupied" mode is entered when an Excel

10 wall module is configured to allow it and if:

•(in the case of the T7460) the bypass button is pressed for four to seven seconds (until the LED blinks),

•(in the case of the T7560) the bypass button is pressed for more than five seconds (until the flashing moon appears).

The Excel 10 FCU Controller can also be forced into the con- tinuous "unoccupied" mode by means of a LONWORKS net- work command (when nviManOccCmd is set to OC_UNOCCUPIED). The Excel 10 FCU Controller will then remain in this mode indefinitely, or until the bypass button is pressed to exit the mode or a network command is sent to clear the mode.

Bypass Push-Button

Excel 10 FCU Controllers may be hardwired to an Excel 10 wall module equipped with a bypass push-button. The bypass push-button has three possible configurations (see Table 17 for further information):

•NONE

•BYPASS_UNOCCUPIED

•BYPASS_ONLY

Override Priority

Excel 10 FCU Controllers can be configured to arbitrate overrides coming from the bypass push-button and the network. There are two possible configurations, having the following meanings:

•LAST_WINS specifies that the last command received from either the wall module or nviManOccCmd determines the effective override state.

•NETWORK_WINS specifies that, regardless of the wall module override state, the effective occupancy mode is

determined by nviManOccCmd (provided it has not been set to OC_NUL).

LED/LCD

LED Override

The wall module’s LED indicates that the FCU Controller is being overridden by either the bypass button or the LONWORKS network.

•LED ON ⇒ "override bypass"

•One flash per second ⇒ "override unoccupied"

•Two flashes per second ⇒ "override standby" or "occupied"

•LED OFF ⇒ no override

•Four flashes per second ⇒ The controller is responding to a LONWORKS network management wink command.

LED Occupancy

The wall module’s LED indicates the effective occupancy mode.

•LED ON ⇒ effective "occupied" or effective "bypass"

•One flash per second ⇒ effective "standby"

•LED OFF ⇒ effective "unoccupied"

•Four flashes per second ⇒ The controller is responding to a LONWORKS network management wink command.

LCD Display

This mode is used only for T7560 Wall Modules. The occupancy mode is represented by the following symbols:

⇒ effective "occupied" or effective "bypass"

⇒ effective "standby"

⇒ effective "unoccupied"

⇒ Controller is OFF

and ⇒ Controller is OFF, frost protection is enabled.

Flashing symbols indicate the "override" mode: ⇒ override "occupied" or override "bypass"

⇒ override "standby"

⇒ override "unoccupied"

⇒The controller is responding to a LONWORKS network

management wink command.

Energy-Saving Features

The "Standby" Mode

The digital input for reading input from an occupancy sensor (usually a motion detector) provides the Excel 10 FCU Con- troller with a means to enter an energy-saving standby mode whenever there are no people in the room. The "standby" mode occurs when the scheduled occupancy mode is "occupied" but the occupancy sensor indicates that the room is nevertheless currently unoccupied. If no occupancy sensor is directly connected to the Excel 10 FCU Controller, an occupancy sensor from another node may be bound to the network input nviSensorOCC. The Excel 10 FCU Controller can also be forced into the "standby" mode by means of a LONWORKS network command (when nviManOccCmd is set to OC_STANDBY). When in the "standby" mode, the Excel 10 FCU Controller uses the "standby" setpoints configured for the heating and the cooling modes.

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