P78 Series Controls for Dual Pressure Applications Installation Instructions
4
P78 controls for dual pressure applications are available with a Single-Pole, Double-Throw (SPDT) switch. Check
the label inside the control cover for the model number, switch action, and electrical rating. Check the wiring
terminal designations on the control switch block, and see the following wiring diagram when wiring the control.
(See Figure 3 and Table 2). Also see
Technical Specifications
.
Refrigerant Connections
IMPORTANT:
Use terminal screws furnished in the switch block. Using other terminal screws will void the
warranty and may damage the switch.
Table 2: P78 Switch Wiring (SPDT)
LP/HP Description
LP
A-C opens on pressure decrease
A-B closes simultaneously
HP
A-C opens on pressure increase
A-D closes simultaneously
Risk of Environmental and Property Damage.
Avoid sharp bends in the capillary tubes. Sharp bends can weaken or kink capillary tubes, which may result in
refrigerant leaks or restrictions of flow.
Risque de dommages environnementaux et dégâts matériels.
Éviter de former des coudes serrés avec les tubes capillaires. Les coudes serrés peuvent affaiblir les tubes
capillaires ou engendrer des pliures, ce qui risque de provoquer des fuites de réfrigérant ou d'en gêner
l'écoulement.
Figure 3: P78 Switch Wiring (SPDT)
