The Parker Sporlan Kelvin II is a standalone superheat controller purpose-built to drive electronic expansion valves (EEV) in commercial and industrial refrigeration systems. Unlike generic PID temperature controllers, it combines pressure transducer and temperature sensor inputs to calculate true superheat in real time, then uses proprietary Sporlan control algorithms to regulate refrigerant flow with minimal hunting. It also replaces mechanical subcooling valves in subcooler applications and provides dedicated modes for chiller, secondary fluid, temperature, and pressure control.

Why Auto PID Matters in Refrigeration

• Pre-tuned for Real-World Loads: The default Supermarket Mode is factory-optimized for typical cold-room and display-case thermal dynamics. Most installations run stable superheat right out of the box—no manual tuning required.
• Adjustable When Needed: For installations where temperature pulldown is too slow or superheat oscillates, the PID constants are accessible via the local display or Modbus, giving experienced technicians full control without specialized software.
• Priority-Based Protection: During pumpdown via the digital input or defrost transitions, superheat control takes priority to protect the compressor from liquid slugging.

One Dial, Six Control Modes

• Superheat Control: True P/T superheat regulation for EEV-equipped evaporators. Supports dual-evaporator configurations through display networking.
• Subcool Control: Combines liquid temperature and minimum superheat control to replace mechanical subcooling valves, reducing hardware cost and leak points.
• Temperature & Pressure Control: Precise regulation of air temperature and refrigerant pressure using SDR or CDS electronic pressure-regulating valves.
• Chiller & Secondary Fluid: Dedicated control strategies for glycol loops and secondary refrigerant systems, expanding the controller beyond direct-expansion applications.

Modbus RTU Connectivity

• Standard RS-485 Port: Communicates directly with any Modbus RTU master (PLC, building management system, or Parker's Network Master) without protocol converters.
• Full Read/Write Access: Remote monitoring includes superheat real-time values, suction pressure, coil outlet temperature, and alarm status. Setpoints and control mode selection are fully editable over the bus.
• Remote Display Chain: The optional remote display unit (Kelvin IId, p/n 952568) daisy-chains on the same RS-485 pair, eliminating separate cable runs for walk-in cold-room installations.

Installation & Environmental Suitability

• DIN Rail Mount: Standard EN 50022 rail; fits inside electrical panels alongside contactors and breakers. Suggested mounting area: 10 in. high × 5 in. wide, minimum 3 in. depth.
• 24 VAC/VDC Power: Operates from a single Class II transformer (24 VAC, 40 VA) or 22–26.6 VDC supply.
• -40 °C Cold Start: Rated for continuous operation from -40 °F to 158 °F (-40 °C to 70 °C), with 0–95 % RH non-condensing. Suitable for unheated equipment rooms and outdoor-rated enclosures.
• Long Sensor Runs: Temperature and pressure sensor leads may be extended up to 100 ft (30.5 m) with 18 AWG wire, accommodating large cold storage layouts without signal drop.

Key Technical Specifications

• Analog Inputs: 4 × temperature (2 KΩ or 3 KΩ NTC surface/air sensors) + 1 × pressure transducer (0.5–4.5 V ratiometric).
• Digital Input: Dry-contact or open-collector interface for pumpdown relay trigger.
• Outputs: 1 × relay (100–240 VAC, 3 A inductive / 28 VDC, 250 mA) for liquid-line solenoid or compressor; 1 × digital output (22–28 VDC, 250 mA).
• Display Variants: SD model with local 4-digit LED + SELECT knob; S model without local display for OEM integration; remote display unit (IId) available.
• Compatible Valves: All Sporlan stepper-motor EEVs (SEI, SEH, SER, ESX) and electronic pressure regulators (SDR-4, CDS-4, CDS-7, CDS-9).
• Refrigerants: Supports most common refrigerants; configured via Modbus or Network Master during setup.