Specifications

76
JOHNSON CONTROLS
Form 201.28-NM1.EN.PED/CE (0211)
MICROPANEL
PROGRAM KEY
Program Key Operation
Various operating parameters are programmable by the
user. These are modified by pressing the PROGRAM
key and then the  (ENTER) key to enter Program
Mode. A listing of the limits of the programmable values
is found below. Note that the Imperial units are exact
values, while Metric units are only approximate.
The ▲ and ▼ (ARROW) keys are used to scroll through
the user programmable values. A value may be changed
by keying in the new value and pressing the  (ENTER)
key to store the new value in memory. The cursor will be
displayed on the screen when a number key is pressed.
The first line of each message will indicate the chiller
default (DEF) value), lowest acceptable programmable
value (LO), and highest acceptable programmable value
(HI). The user programmable value is programmed ON
in the second line of the message.
When the PROGRAM key is first pressed, the following
display will appear indicating the user is in the program
mode:
PROGRAM MODE
PRESS ENTER KEY TO CONTINUE
Pressing the  (ENTER) key again will display the first
programmable selection.
Suction Pressure Cutout
PROGRAM DEF LO HI
SUCTION PRESSURE CUTOUT = XX.X PSIG
The suction pressure cutout is protects the chiller from
a low refrigerant condition. It also helps protect from a
freeze-up due to low or no chilled liquid flow. However,
it is only a back-up for a flow switch and cannot protect
against an evaporator freeze under many conditions.
This cutout is programmable and should generally be
programmed for 1.65 barg (24 PSIG) for chilled water
cooling.
The cutout is programmable between 1.65 and 2.48 barg
(24.0 and 36.0 PSIG) in the Water Cooling mode and
0.34 and 2.48 barg (5.0 and 36.0 PSIG) in the Glycol
Cooling mode. The default value for both modes will be
1.65 barg (24.0 PSIG).
Low Ambient Cutout
PROGRAM DEF LO HI
LOW AMBIENT TEMP CUTOUT = XX.X °F
The low ambient temp cutout allows programming the
outdoor temperature at which it is desired to shut down
the chiller to utilize other methods of cooling.
The cutout is programmable between -18.9°C (-2.0°F)
and 10.0°C (50°F) with a -3.9°C (25°F) default.
Low Leaving Liquid Temp Cutout
PROGRAM DEF LO HI
LEAVING LIQUID TEMP CUTOUT = XX.X °F
The leaving chilled liquid temp cutout is programmed
to avoid freezing the evaporator due to excessively low
chilled liquid temperatures. The cutout is automatically
set at 2.2 °C (36°F) in the Water Cooling mode and
is programmable in the Glycol Cooling mode. In the
Glycol Cooling Mode, the cutout is programmable from
-11.7°C to 2.2°C (11.0°F to 36.0°F) with a default of
2.2°C (36.0°F).
Motor Current Limit
PROGRAM DEF LO HI
MOTOR CURRENT LIMIT = XXX % FLA
The motor current limit %FLA is programmable. This
allows the microprocessor to limit a system before it
faults on high current. Typically, the limit point is set
at 100%. The unload point is programmable from 30 to
100% with a default of 100%.
Pulldown Current Limit
PROGRAM DEF LO HI
PULLDOWN CURRENT LIMIT = XXX % FLA
The pulldown current limit %FLA is programmable.
This allows the microprocessor to limit a system on
pulldown limiting for the purpose of peak time energy
savings. Typically, the limit point is set at 100%. The
pulldown limit point is programmable from 30 to 100%
with a default of 100%. Be aware when using pulldown
motor current limit, the chiller may not be able to load to
satisfy temperature demand.