Murphy controls lcdt

FW Murphy LCDT Series Compressor Controls


  • Monitor Engine or Motor Driven Pumps and Compressors
  • 47 Normally Open (N.O.) or Normally Closed (N.C.) Sensor Inputs
  • CSA* and Factory Mutual** Listed
  • Rated for Hazardous Locations

FW Murphy LCTD Compressor Controls Specs

  • Power: Supplied by CD ignition of an engine, 120 VAC line, or by 12 or 24 VDC battery.
  • Power Inputs (Operating Voltage):
    LCDT-PS-CD (R)-P: 90-250 VDC, CD ignition, positive ground.
    LCDT-PS-CD-N: 90-250 VDC CD ignition, negative ground.
    LCDT-PS-120/24/12: 120 VAC (6 VA), 24 VDC (1 watt), 12 VDC (0.5 watts).
  • Sensor Inputs: Accepts up to 47 sensors (NC version only 45) via a ribbon cable. The LCDT system was designed to be used with sensor switches having normally open or normally closed contacts such as Murphy Swichgage instrument. NOTE: An approved isolation barrier such as a thermocouple type barrier, must be used between sensor switch and input terminals if sensor outputs come from any energy storing device such as a relay or transistor.
  • Relay Outputs Ratings:
    LCDT-PS-CD (R)-P Contact rating: 4A, 1/20 HP, 125/250 VAC/3A, 30 VDC.
    LCDT-PS-120/24/12 Contact Rating: 5A, 28 VDC. 120 VAC (resistive).
  • FET Outputs: LCDT-PS-CD-N rating (for fuel valve and ignition ground): 0.5A @ 250 V.
  • Alarm Relay Contact Rating: 4A, 1/20 HP, 125/250 VAC/3A, 30 VDC.
  • Operating Temperature: Module (head): -40 to 185°F (-40 to 85°C).
  • Power Supply: 0 to 158°F (-18 to 70°C)
  • Storage Temperature: -40 to 302°F (-40 to 150°C).
  • Case: LCDT-NO/NC (module): anodized aluminum.
  • Power Supply (all models): Explosion-proof aluminum.
  • Multiplexer Scan Rate: Scans all 47 sensors in 0.7 sec.
  • Start-Run/Test Timer: Standard 5 minutes, specify other, up to 7 minutes maximum (in 1 minute increments).
  • Laboratory Approvals: CSA* and Factory Mutual System** Listed for Class I, Division 1, Group D, Hazardous Locations.

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