Additional Occupancy Features

Description of Operation

Bypass Mode

The bypass mode (also called Tenant Override) is the equivalent of a temporary occupied mode. Once the bypass mode is initiated, it remains in effect for a set period of time (120 minutes, default). During the bypass mode, the UVC uses the occupied heating and cooling set points, the OAD operates normally, and by default the IAF remains on.

Networked Occupancy Sensor Capability

A networked occupancy sensor can be interfaced with the Occupancy Sensor Input variable to select occupancy modes. When the Occupancy Sensor Input variable is used, it automatically overrides any hard-wired unoccupied binary input signal.

Unit-Mounted Time-Clock

An optional unit-mounted factory-installed electronic 24-hour/7-day time clock can be provided on stand-alone unit ventilator configurations. It is factory wired to the UVC unoccupied binary input and can be set to automatically place the unit into occupied and unoccupied modes based upon its user configured schedule.

Unit-Mounted Tenant Override Switch

A tenant override switch is factory installed in all floor mounted units and is located near the LUI on the unit. This switch provides a momentary contact closure that can be used by room occupants to temporarily force the UVC into the bypass occupancy mode from unoccupied mode.

Note – The Occupancy Override Input can override the tenant override feature. For example, if the network uses the Occupancy Override Input to force the unit into unoccupied mode, then the unit-mounted tenant override switch does not operate as expected. Therefore, McQuay strongly recommends using the Occupancy Sensor Input to control occupancy modes over a network and only using the Occupancy Override Input if there is reason to ensure tenant override does not occur.

Remote Wall-Mounted Sensor Tenant Override Switch

The optional remote wall-mounted sensors include a tenant override switch. This switch provides a momentary contact closure that can be used by room occupants to temporarily force the UVC into the bypass occupancy mode from unoccupied mode.

Note – The Occupancy Override Input can override the tenant override feature. For example, if the network uses the Occupancy Override Input to force the unit into unoccupied mode, then the wall sensor tenant override switch does not operate as expected. Therefore, McQuay strongly recommends using the Occupancy Sensor Input to control occupancy modes over a network and only using the Occupancy Override Input if there is reason to ensure tenant override does not occur.

Remote Wall-Mounted Sensor Status LED

The optional remote wall-mounted sensors each include a UVC status LED. This status LED aids diagnostics by indicating the UVC occupancy mode and fault condition.

Table 13: Remote wall-mounted sensor status LED

Indication	LED operation
Occupied	On continually
Unoccupied	On 1 second/off 9 seconds
Bypass	On continually
Standby	On 9 seconds/off 1 second
Fault	On 5 seconds/off 5 seconds

McQuay OM 751

Bypass Mode