Phoenix REL-SW230/REL-MR Series Industrial Relays Selection Guide

Opening: Reliable Switching Solutions for Industrial Control & Automation

The Phoenix REL-SW230 and REL-MR series represent industrial-grade electromechanical relays tailored for diverse control scenarios—from 230V AC fixed-voltage applications (REL-SW230) to multi-voltage DC/AC universal use (REL-MR). Covering voltage ranges of 4.5V–230V DC/AC, contact configurations (21/21-21/21HC/1IC/1ICT), and regional certifications (AU), these relays feature high switching capacity, industrial-grade durability, and modular design. Widely used in PLC control cabinets, motor drives, HVAC systems, and Australian-market projects, they ensure stable signal/power switching in harsh industrial environments while meeting global regulatory requirements.

I. Core Advantages of the Series

1. Multi-Voltage & Contact Flexibility
   • REL-SW230 series: Fixed 230V AC input, specialized contact materials (F104/B110/B104) for mixed/inductive/precision loads, adapting to general industrial AC control circuits;
   • REL-MR series: Universal voltage compatibility (4.5V/12V/24V/48V DC, 24V AC), diverse contact types (1/2 changeover contacts, high-capacity HC variants, integrated 1IC/1ICT contacts), matching low-voltage instrumentation to high-current machinery control.
2. Industrial-Grade Reliability
   • Wide operating temperature range (-40°C to +85°C), anti-vibration (5g) and anti-shock (50g) design, suitable for workshop floors and outdoor auxiliary equipment;
   • High contact durability: Up to 10⁷ mechanical operations and 10⁶ electrical switching cycles (at rated load), ensuring long service life in 24/7 operations;
   • IP20 protection (housing) with dust-proof design, safe for control cabinet installation.
3. User-Friendly Deployment & Compliance
   • DIN rail (NS 35/7.5) snap-in mounting, plug-in design for quick replacement without rewiring;
   • Visual LED status indicators for real-time switching monitoring, enabling rapid fault localization;
   • AU certification (suffix "AU") for Australian market compliance, MS standard compatibility (suffix "MS") for global projects;
   • Reverse polarity protection (DC variants) and high insulation voltage (≥4kV) to prevent coil damage and ensure operator safety.

II. Product Classification & Detailed Parameter Table

The series is categorized by sub-series (REL-SW230/REL-MR) with sub-variants based on input voltage, contact configuration, special features, and certifications.

1. REL-SW230 Series (230V AC Fixed-Voltage Relays)

230V AC-powered relays with specialized contact materials for targeted load types, ideal for AC control circuits.

2. REL-MR Series (Multi-Voltage Universal Relays)

Universal relays supporting DC/AC input, diverse contact configurations, and regional certifications, for versatile industrial applications.

2.1 DC Input Variants (4.5V/12V/24V/48V DC)

2.2 AC Input Variants (24V AC)

III. Nomenclature Decoding: Understanding the Part Number System

1. REL-SW230 Series

REL-SW230/[Contact Material Code]

• REL: Product series identifier (industrial electromechanical relay);
• SW: Switching relay (fixed-voltage AC input);
• 230: Fixed input voltage (230V AC);
• Contact Material Code:
  • F104 = General-purpose contact (mixed resistive/inductive loads);
  • B110 = High-capacity contact (inductive loads, enhanced current handling);
  • B104 = Precision contact (low-level signal switching).

2. REL-MR Series

REL-MR-[Input Voltage]/[Contact Configuration]-[Special Suffix]

• REL: Product series identifier (industrial electromechanical relay);
• MR: Modular relay (universal DC/AC input);
• Input Voltage:
  • 4,5DC/12DC/24DC/48DC = DC input voltage (4.5V/12V/24V/48V);
  • 24AC = AC input voltage (24V);
• Contact Configuration:
  • 21 = 1 changeover contact (SPDT: 1NO + 1NC);
  • 21-21 = 2 changeover contacts (DPDT: 2NO + 2NC);
  • 21HC = High-capacity 1 changeover contact (16A max switching current);
  • 1IC/1ICT = 1 integrated contact (specialized signal isolation/control);
• Special Suffix:
  • AU = Australian market certification (complies with AS/NZS standards);
  • MS = Multi-standard compatibility (global regulatory compliance);
  • (No suffix) = Standard variant (general-purpose use).

IV. 3-Step Quick Selection Technique

Step 1: Select Series Based on Input Voltage

• 230V AC fixed-voltage control: Choose REL-SW230 series (2960193/2960122/2960054) for dedicated AC circuit switching.
• Multi-voltage (4.5V–48V DC/24V AC) or mixed environments: Opt for REL-MR series (e.g., 2961121/2961406) for universal compatibility.
• Low-voltage instrumentation (4.5V DC): Pick REL-MR 4,5DC variants (2961370/2961367).

Step 2: Match Contact Configuration to Load Requirements

• Single-circuit switching: Select 21 (SPDT) variants (e.g., 2961121/2961150) for 1-group load control.
• Dual-circuit/redundant control: Choose 21-21 (DPDT) variants (e.g., 2961215/2961257) for 2-group load synchronization.
• High-current loads (≤16A): Opt for 21HC high-capacity variants (e.g., 2961312/2961406) for motor/heavy actuator control.
• Precision signal control: Select 1IC/1ICT (2961341/2987338) or B104 (2960054) contact types.

Step 3: Add Special Features for Regional/Environmental Needs

• Australian market projects: Must select AU-suffix variants (e.g., 2961121/2961370) to meet local regulatory requirements.
• Global multi-standard projects: Choose MS-suffix variants (e.g., 2909645/2987891) for cross-border compliance.
• Inductive loads (motors/solenoids): Pick B110 (2960122) or 21HC (2961312) variants for enhanced contact durability.
• Mixed loads (resistive+inductive): Select F104 (2960193) or standard 21 variants (2961105) for versatile use.

V. Recommended Industry-Scenario Combinations

VI. Selection Pitfall Avoidance Guide

1. Voltage Mismatch: 12V DC systems using 24V DC relays → Verify input voltage and select matching variants (e.g., 2961150 for 12V DC) to prevent coil burnout.
2. Australian Certification Neglect: Local projects using non-AU relays → Choose AU-suffix models (2961121/2961370) to avoid regulatory non-compliance.
3. High-Current Overload: 16A motor loads using standard 21 contacts → Opt for 21HC (2961312) or B110 (2960122) variants to prevent contact welding.
4. Contact Type Incompatibility: Inductive loads using precision B104 contacts → Select B110/21HC variants for enhanced arc suppression and durability.
5. Dual-Circuit Needs Using Single-Contact Relays: 2-group load control using 21 variants → Choose 21-21 (DPDT) models (2961215/2961257) to avoid wiring complexity.
6. Global Compliance Oversight: Cross-border projects using standard variants → Select MS-suffix models (2909645/2987891) to meet multi-region regulatory requirements.

Conclusion: Select the Right REL Relay for Stable Industrial Switching

The Phoenix REL-SW230/REL-MR series delivers targeted switching solutions for fixed AC voltage and universal DC/AC control scenarios, combining industrial-grade durability, contact flexibility, and regional compliance.