SECTION 8 - MICROPANEL
JOHNSON CONTROLS
153
Form 201.28-NM1.1
Issue date: 08/06/2021
8
The programmed temperature ensures the micro will
sense a loss of educator oil flow, if the temperature dif-
ferential rises. A small differential of 2.8°C (5.0°F) is
recommended.
Eductor safety time
PROGRAM ◄DEF XXXXX LO XXXXX HI XXXXX
EDUCTOR SAFETY TIME
= XXXX MIN
The educator safety time allows programming the
time period the system is permitted to run if the safety
threshold is exceeded. The safety time is program-
mable for 10 minutes to 1000 minutes with 10 min-
utes as the default. A minimum safety time is recom-
mended to ensure the compressor is not starved for oil
for long periods of time due to the educator circuit not
siphoning oil from the evaporator. A minimum time of
10 minutes is recommended as the program point.
Motor temperature unload
PROGRAM ◄DEF XXXXX LO XXXXX HI XXXXX
MOTOR TEMPERATURE UNLOAD = XXX °F
The motor temperature unload is programmable from
65.6°C (150.0°F) to 121.1°C 250.0°F. The default val-
ue is 115.5°C (240.0°F). The programmed temperature
ensures the micro will sense a rise in motor temperature
due to a lack of compressor cooling. If the temperature
rises above the programmed threshold, the system will
unload the compressor by reducing speed. An unload
temperature of 115.5°C (240.0°F) is recommended to
ensure the system does provides maximum capacity.
Default values
A listing of the low limits, high limits, and default
values for each of the programmable values is noted
in each display and can be found in
. Note that the Imperial units are exact values
while the Metric units are only approximate.
Table 24 -
Programmable operating parameters
Program value
Mode
Low limit
High limit
Default
Suction pressure cutout
Water
cooling (R-134a)
26.1 psig
36.0 psig
26.1 psig
1.80 barg
2.48 barg
1.80 barg
Glycol
cooling (R-134a)
5.0 psig
36.0 psig
26.1 psig
0.34 barg
2.48 barg
1.80 barg
Suction pressure cutout
Water
cooling (R-513A)
30.2 psig
40.7 psig
30.2 psig
2.08 barg
2.80 barg
2.08 barg
Glycol
cooling (R-513A)
7.7 psig
40.7 psig
30.2 psig
0.53 barg
2.80 barg
2.08 barg
Low ambient air temperature cutout
-10.0°F
50.0°F
-2.0°F
-23.3°C
10°C
-18.9°C
Leaving chilled liquid temperature cutout
Water
cooling
36.0°F
2.2°C
Glycol
cooling
11.0°F
36.0°F
36.0°F
-11.7°C
2.2°C
2.2°C
Motor current limit
30% FLA
103% FLA
103% FLA
Pulldown motor current limit
30% FLA
100% FLA
100% FLA
Pulldown motor current limit time
0 min
255 min
0 min
Condenser subcooling setpoint
0.0°F
20.0°F
5.0°F
0.0°C
11.1°C
2.8°C
Unit ID number
0
7
0
Sound limit setpoint
Sound limit
option enabled
0%
100%
0%
Eductor temperature differential
5.0°F
50.0°F
15.0°F
2.77°C
27.8°C
8.3°C
Eductor safety time
10 min
1000 min
30 min*
Motor temperature unload
150.0°F
250.0°F
240.0°F
65.6°C
121.1°C
115.5°C
