JOHNSON CONTROLS
153
SECTION 7 – UNIT CONTROL CENTER
FORM 150.67-NM2
ISSUE DATE: 01/31/2019
7
C U R R E N T F E E D B A C K
O N E P E R U N I T
This mode should be selected when an optional 2ACE
Module is installed to allow combined current moni-
toring of all systems by sensing current on the incom-
ing line.
or
C U R R E N T F E E D B A C K
O N E P E R S Y S T E M
This mode should be selected when an optional 2ACE
module is installed to allow individual current moni-
toring of each system. SYS 1 input is to J7 of the I/O.
SYS 2 input is to J8 of the I/O.
Option 12 – Power Fail Restart:
P O W E R F A I L R E S T A R T
A U T O M A T I C
Chiller auto restarts after a power failure.
P O W E R F A I L R E S T A R T
M A N U A L
After a power failure, the UNIT switch must be tog-
gled before restart at the unit is allowed. NORMALLY
MANUAL RESTART should NOT BE SELECTED.
Option 13 – Soft Start Enable/Disable:
S O F T S T A R T
D I S A B L E D
SOFT START “DISABLED” MUST be selected on all
chillers.
This message may not be viewable on non-European
chillers.
Option 14 – Unit Type:
U N I T T Y P E
L I Q U I D C H I L L E R
The UNIT TYPE message cannot be modified under
the unit keys.
Lead/lag between systems may be selected to help
equalize average run hours between systems on chillers
with 2 refrigerant systems. Auto lead/lag allows auto-
matic lead/lag of the two systems based on an average
run hours of the compressors in each system. A new
lead/lag assignment is made whenever all compressors
shut down. The micro will then assign the “lead” to the
system with the shortest average run time.
Option 9 – Condenser Fan Control Mode:
F A N C O N T R O L
D I S C H A R G E P R E S S U R E
Condenser fans are controlled by discharge pressure
only. This mode must be chosen.
or
F A N C O N T R O L
A M B I E N T & D S C H P R E S S
Do not select this option on R-410A chillers.
Option 10 – Manual Override Mode:
M A N U A L O V E R R I D E M O D E
D I S A B L E D
This option allows overriding of the daily schedule
that is programmed. MANUAL OVERRIDE MODE –
DISABLED indicates that override mode has no effect.
or
M A N U A L O V E R R I D E M O D E
E N A B L E D
Manual Override Mode is enabled. This is a service
function and when enabled, will allow the unit to start
when shut down on the daily schedule. It will auto-
matically be disabled after 30 minutes.
Option 11 – Current Feedback Options
Installed:
C U R R E N T F E E D B A C K
N O N E
This mode should be selected when the panel is not
equipped with current sensing capability.
or
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