U-Line UCBF632-SS12A User Manual & Service Manual page 36

USER GUIDE
°C °F Ohms
-50 -58 803,10
-45 -49 822,90
-40 -40 842,70
-35 -31 862,50
-30 -22 882,20
-25 -13 901,90
-20 -4 921,60
-15 5 941,20
-10 14 960,90
-5 23 980,40
0 32 1000,00
5 41 1019,50
10 50 1039,00
15 59 1058,50
20 68 1077,90
25 77 1097,30
30 86 1116,70
DOOR SWITCH
The Blast Chiller is equipped with a magnetic sensor. When
the door is closed the sensor is activated by a magnet built
into the door. There are two magnets in each door, one at
the top and one at the bottom. This allows the door to be
reversed (only for non Touch Screen version).
Figure 7: Door Switch
Checking the door switch
If the magnetic sensor is faulty or if the wires are broken or
shorted, the display will show "d-r" continuously. To check
the switch, disconnect the wires from the Main Board at
terminals 48 and 49 (see Figure 7 and Figure 8). Ohm out
the switch between the two wires. Close the switch should
be closed when a magnet is present and open it when it
is not. If the switch tests OK, check for corroded, loose,
or missing connections on the terminals. If no problem is
found in the switch or wires, replace the Main Board.
Troubleshooting
°C °F Ohms
35 95 1136,10
40 104 1155,40
45 113 1174,70
50 122 1194,00
55 131 1214,90
60 140 1232,40
65 149 1251,60
70 158 1270,70
75 167 1289,80
80 176 1308,90
85 185 1328,00
90 194 1347,00
95 203 1366,00
100 212 1385,00
105 221 1403,90
110 230 1422,90
150 302 1573,10
V AWG 18
V AWG 18
BR AWG 18
B AWG 18
Touch Screen Version
Figure 8: Door Switch Diagrams
PRESSURE SWITCH
A pressure-regulating switch is installed to prevent
compressor failures or improper operation due to high
discharge pressure. Self-contained models have a high
pressure switch only, while remote units have a double
switch, like the one shown in Figure 9. In older models
both types of applications had a double switch, triggering
the alarm "hp" for either a low or high pressure event. In
some recent remote applications, the pressure switch is
used for pump down purposes also.
Figure 9: Pressure Switch
Pressure Switch Working Principles – Alarm
Connection
The pressure switch has normally closed contacts that open
if the High or Low pressure limits are exceeded. The switch
is connected to the Main Board at terminals 48 and 50
in case of standard controller (48 is a shared connection
with the door switch), and terminals GND and D1 in the
Touch Screen version. When the pressure switch opens
from either a high or low pressure condition, the display will
show the error code "hP" (or message "HIGH PRESSURE" in
the Touch screen version) (see Figure 10).
36
49
SW1
48
Standard Version
Ohm out
Door Switch