SCR19

Supported Applications

The Omega SCR Power Controllers are solid-state devices designed to regulate AC power for electrical resistance heating processes. Documented applications include ovens, furnaces, and heat sealers. These controllers proportion electric power to resistive loads using silicon-controlled rectors (SCRs), trigger circuitry, fuses, and heat sinks mounted on panels.

Important operational constraints defined in the source documentation:

• Resistive Loads Only: The series is not designed for use with transformers, coils, or other inductive-type loads.
• No Patient-Connected Use: These products are not intended for patient-connected applications.

Operating Conditions & Performance

The SCR19 and related series operate within a supply voltage range of 24 to 600 Vac at frequencies of 50/60 Hz. Current ratings available across the family are 40, 60, and 80 A.

• Ambient Temperature: The specified operating ambient temperature is 30° to 122° F for listed power ratings (also cited as 0 to 50°C).
• Cooling Method: Convection cooling.
• Control Signal Input: Standard input is a 4-20 mAdc signal. All inputs are electrically isolated via optical coupling with a minimum voltage requirement of 10 Vdc and control signal isolation rated at 2500 Vac.
• Protection Features: Includes sub-cycle, current-limiting fuses; transient voltage suppression using MOV and RC circuits.

Variations in Control Method

The series offers two distinct methods of proportional control depending on the model suffix:

• Phase-Angle Firing (P): Models with a 'P' designation utilize phase-angle firing. Soft start options are available only for these models.
• Zero-Voltage Switching (Z): Models with a 'Z' designation use zero-voltage switching to minimize electrical noise and inrush current effects on the line.

Configuration Options

The series supports multiple configurations regarding phase, wiring topology, voltage levels, and control interfaces. Selection is driven by specific load requirements and installation constraints.

Phase and Wiring Configurations

• SCR19P: 1-phase, 1-line control.
• SCR19Z: 3-phase, 3-wire, delta or ungrounded wye.
• SCR39P: 3-phase, 3-line control.
• SCR39Z: 3-phase, 2-line control.

Voltage and Current Options

Line voltage is specified via a code in the model number. Available codes include:

• 02: 24 Vac
• 12: 120 Vac
• 20: 208 Vac
• 24: 240 Vac
• 48: 480 Vac

Current ratings are available in 40 A, 60 A, and 80 A increments.

Soft Start and Voltage Limit Options

For phase-angle models, soft start or voltage limit functions can be added using specific suffix codes:

• S9: Soft start 9 seconds
• S15: Soft start 15 seconds
• S30: Soft start 30 seconds
• S60: Soft start 60 seconds
• S120: Soft start 120 seconds
• V: Voltage limit
• X: No soft start or voltage limit

Manual Control Option

A manual input option module with a remote potentiometer is available. To order this configuration, the suffix '-M' must be added to the model number.

Key Product Differences

The series encompasses both SCR19 and SCR39 families, distinguished primarily by physical dimensions and phase control wiring requirements while sharing similar electrical ratings and mounting styles. Both are designed for surface mounting on panels using convection cooling.

• SCR19 Dimensions: 178 mm (7 in) height x 121 mm (4.8 in) width x 102 mm (4 in) depth.
• SCR39 Dimensions: Varies by model; SCR39Z is 178 mm (7 in) height x 244 mm (9.6 in) width, while SCR39P can be up to 365 mm (14.4 in) wide.

Differentiation between 'Phase-Angle Firing' and 'Zero-Voltage Switching' models is indicated by the model suffix ('P' or 'Z'). Diagnostic indicators are provided for shorted/open SCR conditions, reversed signal input, and mA/V status. Replacement fuses (e.g., SCR-210A015U01) correspond to specific current ratings of 40 A, 60 A, and 80 A.