NuAire LabGard NU-560-400, Operation & Maintenance Manual

Page: 33 / 103

OM0295
Rev 2 September 2020 Page 33 of 103
6.1.5.7 System Information
This menu item provides the cabinet model number, serial number, and software revision.
6.1.6 Night Setback (Optional)
The optional night setback feature is used to reduce the exhaust air volume during non-usage periods resulting in
conditioned air energy savings. For the night setback to operate, a control valve must be installed (i.e. NU-951-012
motorized air tight butterfly valve) to provide the means for reduction of exhaust airflow.
The night setback is initiated by either closing the contacts on the main control board or enabling the night setback
icon on the display. If both are used, the contacts on the main control board have priority over the display icon.
Once the contact is closed or icon is pressed the internal blower and fluorescent lights will be turned off and
remain inoperable. The exhaust valve will be closed to a percentage of the original setpoint typically to maintain a
minimum of 100 fpm (.51 m/s) and the display will indicate night setback active. The sliding window can be closed
and the UV light turned on if installed.
NOTE: If night setback exhaust airflow is reduced by the Building Automation System (BAS) and not by the NuAire
Model NU-951-012 valve, it would still be recommended to use the contacts on the main control board to initiate
the night setback option to display night setback active, inhibit exhaust alarms, light and internal blower.
6.1.7 Remote Override (Optional)
The optional remote override feature is used to remotely control the operation if the cabinet. A typical application
would be in a Bio Safety Level three facility that had a room exhaust system failure.
The failure mode could signal the remote override contacts to close and not allow any usage of the cabinet. Once
the remote override contacts are closed, the internal blower and fluorescent lights will be turned off and remain
inoperable. If an exhaust motorized airtight butterfly valve (NU-951-012) is present the valve will close to seal or
optionally fully open the exhaust system.
The display will indicate “Remote Override ”. Once the remote override contacts are broken, normal operation will
resume.
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