EZ-ZONE® ST Solid State Controller

Integrated Control Loop Makes Solving the Thermal Requirements of Your System Easy

The EZ-ZONE ST integrated solid state controller from Watlow offers a complete thermal system control solution in a single package. Features include a PID temperature controller connected to a high-amperage solid state relay with the option of adding a properly sized heat sink, an over- and under-temperature limit, a power shut-down contactor and digital communications in one complete and professionally engineered product.

Because the solid state controller system is modular and scalable, a user only pays for what is needed. Stacking the EZ-ZONE ST integrated controller into multiple configurations enables flexibility to standardize the product platform to solve a wide range of application needs.

Features & Benefits

Multiple mounting options: back panel or DIN-rail mount

Off-the-shelf system solution improves reliability, reduces installation costs and eliminates incompatibility issues associated with using multiple brands

Ability to communicate with programmable logic controller (PLC), personal computer (PC) or operator interface terminal (OIT)

Complies with IP2X to increase user safety

±0.1 percent temperature accuracy


Description Information
Control/Limit Loops 1/1
Alarms 2
Mounting DIN-rail
Profiling Yes
Max Output 75A
Output Firing Zero Cross, Phase Angle
Phase Configurations 1
Ambient Operating Range -18 to 70°C (0 to 158°F)
Agency Approvals UL® , CSA, CE, IP65/NEMA 4X indoor use RUI, RoHS, W.E.E.E., FM (limit feature)
Communication Protocols Standard Bus, Modbus® TCP, Modbus® RTU
TRU-TUNE®+ Adaptive Control Yes
Remote Limit Reset Yes
Display Height 2.05 in. (52.07 mm)
Warranty (Years) 3

Related Documentation

  • User Manuals

    EZ-ZONE ST User Manual

  • Agency Approvals

    Agency Approvals for Watlow Controllers

    CCC Winona Exemption Letter

  • Brochures

    Thermal Solutions for Medical and Clinical Applications

    Thermal Solutions for Photovoltaic Processing Equipment

  • Training and Education

    Phase Angle function - Oscilloscope Video

    Current Limit function - Oscilloscope Video

    Soft Start Function - Oscilloscope Video

    Thats Easy! 1: Installing a USB-to-485 Converter and EZ-ZONE Configurator Software (7 min)

    Thats Easy! 2: Configuring a Controller with EZ-ZONE Configurator (11 min)

    Thats Easy! 3: Changing Closed Loop Set Point on EZ-ZONE (7 min)

    Thats Easy! 4: Changing Control Mode on EZ-ZONE (10 min)

    Thats Easy! 5: Changing the Display Units on EZ-ZONE (6 min)

    Video Tutorial Catalog, Rev. N

  • Catalogs

    Controller Catalog (Section) - Data Loggers

    Controller Catalog (Section) - Integrated Multi-Function Controllers

    Controller Catalog (Section) - Temperature and Process Controllers

    Sensor & Controller Catalog

  • Software & Demos

    Comm7 - Communication Diagnostic Software ver.7

    EZ-ZONE Register List for communication protocols and LabView

    EZ-ZONE Configurator Software Download v6.1

    EZ-ZONE Default Implicit Assembly

    EZ-ZONE Family DeviceNet EDS File

    EZ-ZONE Profibus Demo Project

    Modbus RTU Diagnostic program for EZ-ZONE PM, RM and ST

    Modbus RTU program for EZ-ZONE PM, RM and ST

    Modbus TCP Diagnostic program for EZ-ZONE PM, RM and ST

    Sample Modbus Communications Modules for Programmers

    Silver Series EM Sample Project (480 x 272), Rev A

    Silver Series EM Sample Project (800 x 480), Rev A

    SpecView SCADA Software Download

  • Specification Sheets

    Combined Branch Protection and Semiconductor Fusing

    DIN-RAIL Semiconductor Fusing

    EZ-ZONE Configurator Software

    EZ-ZONE LabVIEW Instrument Driver


    Communication Adapters

    Silver Series EM Operator Interface Terminal

    SpecView SCADA Software

  • White Papers

    Boiler Control Application using Cascade Control

    Controls Integration Guide

    EZ-ZONE Profibus Technical Reference

    EZ-ZONE ST Comms Wiring Using B&B 485SD9TB Converter

    EZ-ZONE ST Comms Wiring Using Serial Gear Converter

    PID Practical Guide

    RUI/Gateway DeviceNet Configuration & Programming Using Allen-Bradley PLC

    RUI/Gateway & Modbus RTU Configuration & Programming Examples Using an Allen-Bradley MicroLogix 1200 PLC

    RUI/Gateway Modbus TCP Configuration & Programming Using KEPServerEX

    Sample ST 32-bit Modbus RTU Packet

    SCCR - Short Circuit Current Rating for Watlow Power Controls

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Quality Certificates

ISO 90012008 Certificate - Controllers Winona