ETI SST-2 Freeze Protection Thermostat

DESCRIPTION

The C-UL-US listed SST–2 Freeze Protection Thermostats replace electromechanical thermostats in cost-sensitive applications requiring ground fault equipment protection (GFEP). The SST–2 is listed by Underwriters Laboratories to Standard UL 873 for Temperature- Indicating and -Regulating Equipment.

The SST–2 operates heaters at temperatures below 40°F (4.4°C) and turns them off above 42°F (5.5°C). The external temperature sensor (supplied) is a NEC Class 2 device rated for wet locations.

The SST–2 features a built-in 30 mA GFEP that is 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.

The SST–2 includes an alarm relay with an isolated SPDT 1 AMP contact. The alarm relay is reverse acting and is normally closed unless there is a ground fault condition, GFEP circuitry fails a test, or when there is a bad temperature sensor.

The SST–2 Freeze Protection Thermostats operate from automatically selected operating voltages of 120, 208, 240 or 277 volts, single-phase. They control heater loads of up to 30 amps while consuming less than 2 watts when idling. The temperature sensor is an NEC Class 2 device that can be located up to 2,000' (610 m) away from the SST. They operate in non-hazardous environments in a temperature range extending from −40° to 131°F (−40° to 55°C). The rugged non-metallic enclosure is appropriate for installation in indoor or outdoor locations suitable for NEMA 4x applications.

For complete information describing its application, installation and features, please contact Customer Service or check on the web at www.networketi.com.

General

Area of use

Nonhazardous locations

Approvals

C-UL-US Listed Type 873 Temperature Regulating Equipment

Enclosure

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
GFEP (red) ground fault condition
GFEP (red, flashing) failed
GFEP (red, flashing, rapid) GFEP test in progress

Remote Interface (SST–2 only)

Alarm relay

Isolated SPDT 1 AMP Class 2 contact

Summary alarms

No Power
Ground Fault Condition
GFEP function test failure
Bad or missing Thermistor

Control

Supply voltage

120, 208, 240 or 277 volts, single phase (automatically selected)

Contact type

Two Form A DPST

Maximum ratings

Voltage: 277 VAC
Current: 30 amps

High Limit Thermostat

Set point

40°F (4.4°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 and heaters every 24 hours

Manual test/reset

TEST/RESET switch of front panel

Environmental

Operating temperature

−40°F to 130°F (−40°C to 55 °C)

Storage temperature

−67°F to 167 °F (−55°C to 75 °C)

Order Number

Description

22744

Model SST–2 Freeze Protection Thermostat

19272

Temperature Sensor (included)

The ETI logo, Snow Switch, Floorstat, Tracon, and Heat Systems are registered trademarks of Environmental Technology, Inc. We Manage Heat, Digital Anticipation, ComfortTouch, Dry Floors, LCD, APS, SC, GIT, SIT, CIT, ES, HSC, FWT, GPT, ADH, EDH, RCM, RCD, RCU, FMC, SMT are trademarks of Environmental Technology, Inc. Copyright 2000, All rights reserved.

Features & Benefits

DESCRIPTION

SPECIFICATIONS

ORDERING INFORMATION