INVENSYS EUROTHERM HEATER POWER CONTROLLER 7100A 25A SELF #2 12:52

1. Product Name & Model:

• Manufacturer: Invensys Eurotherm (A highly respected British manufacturer of industrial automation and control systems. The Eurotherm brand is now part of Watlow following a series of acquisitions).

• Product Line / Series: 7100A

• Function: Heater Power Controller (More specifically, a Solid-State Relay or SSR).

• Key Specification: 25A (25 Amperes). This is its maximum output current rating.

• Key Feature: SELF (Short for Self-contained).

2. Key Features & Functionality:

• Core Purpose: This device is used to precisely and rapidly switch electrical power to an industrial heating element (e.g., in a furnace, oven, or plastic molding machine). It acts as the high-power “switch” that is commanded by a lower-power temperature controller.

• Technology: It is a Solid-State Relay (SSR). Unlike electromechanical contactors that use moving parts and physical contacts to switch power, an SSR uses semiconductor components (thyristors, SCRs, or Triacs). This allows for:

  • Very fast, silent switching.

  • Long life with no parts to wear out from arcing.

  • Precision control through phase-angle or burst-fire (zero-cross) control methods.

• The “SELF” Designation: This is a critical feature. It means the unit is self-contained.

  • Integrated Heat Sink: It comes with its own attached aluminum heat sink (the finned metal structure). This is essential for dissipating the significant heat generated by the internal semiconductors when switching high currents.

  • Easy Installation: The self-contained design simplifies mounting (often via a bracket or clip) and wiring, as it does not require a separate, large external heat sink assembly.

• Control Input: It accepts a standard low-voltage analog control signal from a Eurotherm or other brand temperature controller (e.g., 4-20 mA or 0-10 V DC). This signal tells the power controller what percentage of full power to deliver to the heater.

3. Technical Specifications (Inferred from Standard 7100A Models):

• Output Current: 25 Amps AC (The specific voltage rating, e.g., 240V AC or 480V AC, will be stated on the unit’s label).

• Control Input: Typically 4-20 mA or 0-10 V DC.

• Features: Likely includes status LEDs for power and output indication, and built-in snubber circuits for protection against voltage transients.

• Mounting: Designed for direct panel mounting via its integrated heat sink.

4. Intended Use & Context:
This is a professional-grade industrial component found in systems requiring precise temperature control, such as:

• Industrial Ovens & Furnaces

• Plastic Processing Machinery (Injection Molders, Extruders)

• Packaging Machinery

• Food Processing Equipment

• Laboratory Test Chambers