Service
Operation & Maintenance Manual 51
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Dual Pressure Switch
■
Differential Pressure Switch
Differential pressure switch is also used for checking lubrication trouble. When the differential pressure between con-
denser and evaporator is larger than the setting value(5kg/cm
2
), the switch will be closed. Contrary, when the setting
value is under the setting value, the switch will be opened. This switch is also returned to be closed automatically when
the differential pressure is recovered from low pressure status.
Dual pressure switch has low pressure cutout switch and high pressure cutout switch inside. The cutoff points can be
adjustable. The factory setting values are shown in the below.
The low pressure switch and the high pressure switch are normally closed and tripped to opening when the detected
pressure exceeds the setting value. After recovering from high pressure or low pressure status, the switch resets to
normal position automatically.
Low Pressure Cutout
3.2kgf/cm
2
High Pressure Cutout
22kgf/cm
2
Table 18
Fig. 27
Fig. 28
