Emerson Liebert Deluxe System/3 DH - Manual (Page 38)

Advanced Microprocessor with Graphics Control Setup
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4.11.3 Read Digital Inputs
The four custom alarm inputs can be defined to be digital inputs. Digital inputs are used to sense cus-
tomer devices for status display purposes only and will not activate the audible alarm.
4.11.4 Set Up Digital Inputs
A digital input is enabled by defining one of the four custom alarms to be STATUS ONLY type in the
alarm setup screen. The digital input is given a name by specifying it to be one of the optional alarms
or a custom text alarm. See 4.4.3 - Setup Alarms and 4.4.4 - Set Up Custom Alarms.
4.12 Main Menu (AG)—View Run Hours Log
Selecting VIEW RUN HOURS LOG will step to the following menu:
• VIEW 24 HOUR RUN TIME HISTORY
• VIEW TOTAL RUN HOURS
4.12.1 View 24 Hour Run Time History
The history of each load for every hour during the past 24 hours is displayed in the run hour history.
The percentage of each hour that the load was on is displayed from 0 to 100% in increments of 5% or 3
minutes. Loads with a variable output are displayed as a percentage of their capacity for an hour. For
example, a variable load that is 50% on for 1/2 of the hour will be displayed as 25% on for that hour.
4.12.2 View Total Run Hours
The total operating hours of all major components in the unit can be monitored from the display and
are retained in nonvolatile memory. Run times are available for the following:
• COMPRESSOR 1
• COMPRESSOR 2
• GLYCOOL COIL (or DUAL COOL COIL)
• FAN
• HUMIDIFIER
• REHEAT 1 (or HOT WATER REHEAT)
• REHEAT 2
• REHEAT 3
• CHILLED WATER COIL
• HEAT REJECTION
The component run hours for each individual component can be reset by selecting the run hours dis-
play screen for the desired component, then pressing ENTER within five (5) minutes of applying
power to the control. The user will then be prompted to press ENTER to clear the selected compo-
nent's run hours.
4.13 Load Control Features
4.13.1 Short Cycle Control
The control system monitors both compressors and prevents each from turning on within 3 minutes of
being turned off. If this (on, off, on) occurs too often, ten (10) times in one hour, a Short Cycle alarm
could occur.
4.13.2 Sequential Load Activation Control
The control allows only one load output to be energized at a time on a restoration of power or micro-
controller reset. Each additional load output will be activated at one second intervals until desired
operating conditions have been met.
NOTE
A component’s run hours should BE RESET ONLY when the component has been replaced.