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

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.


Service done right

FW Murphy Service Network

Palmer Johnson's six-location factory-authorized service center network features:

  • Factory-trained technicians
  • Field service
  • Onsite troubleshooting and diagnostics
  • Unit removal and installation

For FW Murphy service, call 1-800-341-4334.

Learn more

Madison, WI

Service Center

Service: (608) 834-5206

1835 Haynes Dr
Sun Prairie, WI 53590


Dallas, TX

Service Center

Service: (817) 505-2430

608 112th St
Arlington, TX 76011


Denver, CO

Service Dealer

Service: (720) 724-0033

5151 E 56th Ave
Commerce City, CO 80022


Kansas City, KS

Service Center

Service: (913) 202-6944

15360 South Mahaffie St
Olathe, KS 66062


Los Angeles, CA

Service Center

Service: (562) 356-1590

12020 Bloomfield Ave
Santa Fe Springs, CA 90670


Oklahoma City, OK


Sales: (800) 341-4334

Oklahoma City, OK 73128


Phoenix, AZ

Service Dealer

Service: (602) 253-0214

2401 S. 19th Street
Phoenix, AZ 85034


San Francisco, CA

Service Dealer

Service: (510) 342-2212

1930 W Winton Ave #14
Hayward, CA 94545


St. Louis, MO

Service Center

Service: (636) 203-9811

578 Rudder Rd
Fenton, MO 63026


Philadelphia, PA

Service Dealer

Service: (215) 822-8300

159 Discovery Dr
Colmar, PA 18915


Fort Myers, FL

Service Dealer

Service: (239) 693-7477

4821 Waycross Road
Fort Myers, FL


Vancouver, British Columbia

Service Center

Service: (604) 879-6731

6741 Cariboo Rd Unit 205
Burnaby, British Columbia V3N 4A3


Edmonton, Alberta

Service Center

Service: (780) 434-9578

3804 53rd Ave NW
Edmonton, Alberta T6B 3N7


Seattle, WA

Service Center

Service: (425) 251-3434

1710 136th Ave E Suite 200
Sumner, WA 98390


RECON Equipment Center, WI

Service Center

Service: (608) 834-5220

1828 Haynes Dr
Sun Prairie, WI 53590

Map of Palmer Johnson Power Systems locations