SST-3 Electronic Thermostat Heat-Trace Control (Discontinued)

Electronic Thermostat

Features & Benefits

  • Adjustable set point, 34°F - 150°F (1°C - 65°C)
  • Automatic supply voltage selection, 100 - 277 VAC
  • Two-pole contactor switches up to 30 AMP heater loads
  • Alarm relay with isolated contact
  • Integral 30 mA GFEP
  • C-UL-US listed
  • Simple to install and operate
  • Minimum energy costs

SST-3 Adjustable Set Point Thermostat

SST-3 Dimensions

SST-3 Thermostat Dimensions



SST-3 Datasheet SST-3 Manual  SST-3 Installation Sheet

The Tracon Model SST-3 Adjustable Set Point Thermostat Heat-Trace Control provides process temperature maintenance in cost-sensitive applications requiring ground fault equipment protection (GFEP). The SST–3 adjustable set point thermostat protects processes and equipment from damaging temperatures and/or viscosities by maintaining an adjustable temperature set point from 34°F to 150°F (1°C to 65°C). Typical applications include freeze protection, hot water temperature maintenance, and flow assurance/viscosity maintenance.

The thermostat operates heaters at temperatures below the configured set point. It turns them off when the temperature rises 2°F (1°C) above the set point. The adjustable temperature set point is configured via the front panel. The external temperature sensor (supplied) is a NEC Class 2 device rated for wet locations.

ETI SST-3The SST-3 Adjustable Set Point Thermostat features a built-in 30 mA GFEP, digitally filtered to minimize false tripping. A ground fault must be manually reset with the TEST/RESET switch before heater operation can be resumed. The GFEP function is automatically tested along with the heaters whenever power is applied and once every 24 hours thereafter for additional safety. An optional operational mode allows the GFEP to alarm without disabling heater operation for use with critical fire protection systems.

The unit includes an alarm relay with an isolated SPDT 1 AMP contact. The alarm relay is reverse acting and is normally energized unless there is a ground fault condition, GFEP circuitry fails a test, when there is a bad temperature sensor, or when there is a low limit temperature condition.

Powered by automatically selected operating voltages from 100 to 277 volts (single-phase) the SST–3 Adjustable Set Point Thermostat controls heater loads up to 30 amps. The temperature sensor is an NEC Class 2 device that can be located up to 2,000′ (610m) away from the thermostat.


Area of use Nonhazardous locations
Approvals C-UL-US Listed, Type 873 Temperature Regulating Equipment & Type 1053 Ground-Fault Sensing and Relaying Equipment
Protection NEMA 4X
Cover attachment Polycarbonate cover, machine screws
Entries 1 × 3/4″ entry (bottom right) for NEC Class 2 connections
3 × 1-1/16″ entries (bottom left and left) for supply and load power
Material Polycarbonate
Mounting Wall mounted
Front Panel Interface
Status indicator SUPPLY (green) power applied
SUPPLY (green, flashing) bad thermistor
HEAT (yellow) call for heat
ALARM (red) Alarm Condition:
• LL Low Temperature Limit
• 9FA Ground Fault Condition
• 9FC Ground Fault Circuit (function test failure)
• Prb Temperature Probe (Bad or Missing Thermistor)
GFEP (red, flashing, rapid) GFEP test in progress
Remote Interface
Alarm relay Isolated SPDT 1 AMP Class 2 contact
Summary alarms No Power
Ground Fault Condition
GFEP function test failure
Bad or missing Thermistor
Supply voltage 100 – 277 VAC auto-select; 50/60 Hz
Contact type Two Form A DPST
Maximum ratings Voltage: 277 VAC
Current: 30 Amp Maximum Resistive Load
Temperature Sensor
Set point 34°F – 150°F (1°C – 65°C)
Dead band 2°F (1°C)
Sensor type Thermistor network
Circuit type NEC Class 2
Lead length Up to 2,000′ (610m) using 12 AWG 2-wire jacketed cable
Up to 500′ (152m) using 18 AWG 2-wire jacketed cable
Ground Fault Equipment Protection (GFEP)
Set point 30 mA
Automatic self test Mode A: Verifies GFEP function before contactors operate
Mode B: Verifies GFEP function every 24 hours
Manual test/reset TEST/RESET switch of front panel
Operating temperature Enclosure: −31°F to 130°F (−35°C to 55°C)
Temperature Sensor: −40° to 300°F (−40° to 149°C)
Storage temperature −67°F to 167°F (−55°C to 75°C)


Order Number Description
24492 Model SST–3 Adjustable Set Point Thermostat (One temperature sensor included.)
19272 Temperature Sensor