NuAire Labgard NU-430-400, Operation & Maintenance Manual

Page: 88 / 99

OM0228 Page 88 of 99
February/2014
9.0 Remote Contacts
The NU ‐ 430 has several contact closures for remote sensing of various functions.
9.1 Fan Relay
The fan relay contacts are dual normally open contact closure outputs which are activated whenever the blower is turned
on. Contact ratings are 250 VAC maximum at 2 Amps.
9.2 Alarm Relay
The alarm relay contacts are dual normally open contact closure outputs which are activated whenever an airflow alarm
condition occurs. An airflow alarm condition will occur if either airflow sensor detects 5 consecutive 2 second airflow
readings above or below the alarm limits. Contact ratings are 250 VAC maximum at 2 Amps.
9.3 AUX Relay
The AUX relay contacts are common, normally open and normally closed contact closure outputs which are activated
whenever the blower is turned on. However, the AUX relay does have some conditional logic programmed to aid the
supply On/Off and exhaust delay options. The relay will activate whenever the blower is turned on and stay on unless after
5 minutes there is a low exhaust alarm, then the relay will de ‐ activate. If exhaust is sufficient, the relay will stay active. If
the blower is then turned off, the relay will stay active for one minute, then de ‐ activate. The AUX relay may also be
selected to operate the same as the fan relay, reference the AUX relay function in the option menu. Contact ratings are
250 VAC maximum at 2 Amps.
9.4 Remote Override
The remote override contacts are (no power) shorting contacts only, which when closed, indicates to the control system to
shut down the cabinet. The display will indicate remote override, inhibit all alarms, fluorescent light, internal blower and
close the exhaust valve (i.e. NU ‐ 951) if present.
9.5 Night Setback
The night setback contacts are (no power) shorting contacts only, which when closed, indicates to the control system to
place the cabinet into night setback. The display will indicate night setback active, inhibit exhaust alarms, fluorescent light
and internal blower.