WD_2021

71R SERIES

PRESSURE SWITCHES

RED DOT TRINARY ™ PRESSURE SWITCHES - GENERATION II

This switch assembly performs three distinct func- tions. The first function prevents the compressor from operating if system charge is lost or ambient temperature is too low. The second stops compres- sor if head pressure increases to unsafe levels. It automatically resets when pressure drops back to normal. The third function is a shutter/fan override switch that keeps head pressure within normal range by opening shutters or operating engine fan to increase air flow across condenser when head pressure rises above set valve. Install Trinary on liquid side of a/c system between condenser and expansion valve. For use with R-12 and R-134a systems.

OPENS

CLOSES

Low Pressure Protection

22.5 ± 7.5 PSIG

40 Psig Maximum ( Rising Pressure ) 230 ± 20 PSIG 200 - 230 PSIG ( Rising Pressure )

( Descending Pressure )

High Pressure Protection Shutter Fan/Override

325 ± 25 PSIG 35 - 60 PSIG

Below Closing Pressure

RD-5-4585-0P MOUNTING CONFIGURATION 71R7600

71R7500

RD-5-4620-0P

3 ⁄ 8 ” - 24 UNF-2A Male thread with bulkhead seal, 2-012 O-Ring Shutter/fan switch is normally open

3 ⁄ 8 ” - 24 UNF-2A Male thread with bulkhead seal, 2-012 O-Ring Shutter/fan switch is normally closed

SWITCHES

ELECTRICAL 7 AMP Resistive 4 AMP Inductive 28 VOLT D.C. Maximum 2.50 Series Male Tab Terminals TRINARY ™ E/C Connection end of TRINARY TM

71R7550

71R7650

RD-5-4583-0P

RD-5-4625-0P

7 ⁄ 16 ” - 20 UNF-2B Female thread for male Schrader Shutter/fan switch is normally open

7 ⁄ 16 ” - 20 UNF-2B Female thread for male Schrader Shutter/fan switch is normally closed

4

3 1 2

RED DOT TRINARY TM HARNESS

Terminals 1 & 2 Controls Clutch High/LowPressure Protection Terminal 1: To compressor clutch “compressor” black wire Terminal 2: To thermostat “AC/Thermostat” black/white wire Terminals 3 & 4 Controls Fan Clutch or Shutters Terminal 3: To solenoid valve “override” yellow wire Terminal 4: To ignition “DC power” orange wire

71R4501 RD-5-12150-0P TRINARY TM boot ( provides a molded 4 wire connection to Trinary switch; lead wires are 28” long. ) helps eliminate terminal corrosion and breakage.

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