Phoenix RIF Series Industrial Interface Relay Modules Selection Guide

Opening: Isolated Signal Conversion & Power Amplification Solutions for Industrial Control

The Phoenix RIF series is a portfolio of industrial-grade interface relay modules designed for signal isolation, voltage conversion, and power amplification in factory automation systems. Covering two core series (RIF-2/RIF-3) with diverse voltage inputs (24DC/24AC/120AC/230AC/125DC), contact configurations (2×21/3×21/4×21), and special variants (EX explosion-proof, AU certification), these modules feature electrical isolation (up to 4kV), anti-vibration construction, and compatibility with PLC/DCS control signals. Widely used in process control, hazardous area equipment, and high-reliability industrial systems, they ensure safe and stable signal transmission between low-voltage control circuits and high-power load circuits.

I. Core Advantages of the RIF Series

1. Multi-voltage & multi-contact flexibility:
   • Supports DC (24V/125V) and AC (24V/120V/230V) input voltages, adapting to global industrial control system standards;
   • Contact configurations: 2×21 (2 normally open), 3×21 (3 normally open), 4×21 (4 normally open) for different load circuit branching needs;
   • Dual input types (LV/LDP) for low-voltage and low-dropout scenarios, matching diverse control signal levels.
2. Industrial-grade isolation & protection:
   • 4kV electrical isolation between control and load circuits, preventing cross-interference and protecting PLC/DCS controllers;
   • Wide operating temperature (-40°C to +70°C), anti-vibration (10g) and anti-shock (50g) design, suitable for harsh factory and outdoor environments;
   • EX explosion-proof variants (suffix /EX) for Zone 2/22 hazardous areas, complying with ATEX/IECEx standards.
3. Special certification compatibility:
   • AU-certified models (suffix AU) for Australian market compliance;
   • MH (metal housing) variants for enhanced electromagnetic shielding in high-interference scenarios.
4. Modular installation convenience:
   • DIN rail (NS 35/7.5) mounting, pluggable relay inserts for quick maintenance without rewiring;
   • LED status indicators for real-time monitoring of relay activation, reducing fault diagnosis time.

II. Product Classification & Detailed Parameter Table

The RIF series is categorized by core series (RIF-2/RIF-3) and sub-type (RSC/RPT/BSC/BPT) based on functional focus, with sub-variants for voltage input, contact count, and special certification.

1. RIF-3 Series (3-Contact Interface Relays)

Designed for 3-channel load circuit control, with 2×21/3×21 contact configurations, suitable for medium-scale multi-load control scenarios.

2. RIF-2 Series (4-Contact Interface Relays)

4-channel load control modules with richer voltage options, special certifications (EX/AU), and explosion-proof variants, suitable for large-scale and hazardous environment control.

2.1 RSC (Signal-Controlled Sub-type)

2.2 RPT (Power-Controlled Sub-type)

2.3 BSC/BPT (Basic Type) & Special Variants

III. RIF Series Nomenclature Decoding

RIF-[Series]-[Sub-type]-[Voltage Type]-[Input Voltage]/[Contact Count]-[Special Feature]

• RIF: Product series identifier (industrial interface relay module for signal isolation and load control).
• Series:
  • RIF-2 = 4-contact relay (for large-scale 4-channel load control, supports special certifications/explosion-proof);
  • RIF-3 = 2/3-contact relay (for medium-scale 2-3 channel load control, compact structure).
• Sub-type:
  • RSC = Signal-controlled relay (for low-voltage PLC/DCS control signals, high isolation);
  • RPT = Power-controlled relay (for high-voltage power signals, high load capacity);
  • BSC = Basic signal relay (cost-effective, general signal switching);
  • BPT = Basic power relay (cost-effective, general power switching).
• Voltage Type:
  • LV = Low-voltage AC input (24AC/120AC/230AC, compatible with global AC standards);
  • LDP = Low-dropout DC input (24DC/125DC, low power consumption for PLC signals);
  • MH = Metal housing (enhanced EMI shielding for high-interference scenarios).
• Input Voltage: 24DC/125DC/24AC/120AC/230AC (matches control system voltage standards).
• Contact Count: 2×21/3×21/4×21 (×21 denotes standard 10A/250V AC contact, number indicates quantity of normally open contacts).
• Special Feature:
  • EX = Explosion-proof (ATEX/IECEx certified for Zone 2/22 hazardous areas);
  • AU = Australian market certification (complies with AS/NZS standards);
  • (suffix omitted) = Standard industrial-grade (no special certification).

IV. 3-Step Quick Selection Technique

Step 1: Select Series Based on Contact Count Requirement

• 4-channel load control (large-scale branching): Choose RIF-2 series; select EX variants for hazardous areas, AU variants for Australian market projects.
• 2-3 channel load control (medium-scale): Opt for RIF-3 series; 3×21 for multi-load, 2×21 for critical dual-circuit control.

Step 2: Match Sub-type & Voltage to Control Signal

• Low-voltage PLC/DCS signals (24V DC): Select LDP low-dropout variants (RSC/RPT-LDP-24DC, e.g., 2903300/2903320) for low-power control signal compatibility.
• AC control signals (24AC/120AC/230AC): Choose LV low-voltage variants (RSC/RPT-LV-xxAC, e.g., 2903316/2903292); 120AC for North America, 230AC for EU/Asia.
• High-voltage DC (125V DC): Pick LDP-125DC variants (2903319/2903324) for battery-powered or high-voltage DC systems.
• Cost-effective general scenarios: Select BSC/BPT basic types (2900932/2900936) for non-critical load control.

Step 3: Add Special Features for Environmental/Market Needs

• Hazardous areas (Zone 2/22, chemical/mining): Choose EX explosion-proof variants (2909845/1047031) to comply with safety standards.
• Australian market projects: Select AU-certified models (1173451/2908332/1021766) for local regulatory compliance.
• High-interference environments (inverters/motors): Opt for MH metal housing variants (1021766) to enhance EMI shielding.

V. Recommended Industry-Scenario Combinations

VI. Selection Pitfall Avoidance Guide

1. Series-contact mismatch: 4-channel load using RIF-3 3-contact modules → Select RIF-2 4×21 variants (e.g., 2903320) to avoid insufficient contact channels and circuit multiplexing.
2. Hazardous area oversight: Explosive environments using non-EX relays → Choose EX variants (2909845/1047031) to prevent safety risks and regulatory non-compliance.
3. Voltage type error: PLC 24V DC signals using LV AC relays → Pick LDP DC variants (2903300) to ensure signal compatibility and avoid relay non-activation.
4. Market certification neglect: Australian projects using non-AU models → Select AU-certified relays (1173451/2908332) to meet local regulatory requirements.
5. High-interference scenario oversight: Inverter-proximal relays using plastic housing → Opt for MH metal housing (1021766) to suppress EMI and prevent false triggering.

Conclusion: Select the Right RIF Relay for Industrial Signal-Load Isolation

The Phoenix RIF series provides targeted interface relay solutions for industrial signal isolation and load control, covering multi-voltage input, multi-contact configuration, and special certifications for hazardous/market-specific scenarios.