Phoenix VAL-MS 320/275 Series Surge Protection Devices (SPD) Selection Guide

Opening: Targeted Overvoltage Protection for 320V/275V Low-Voltage Industrial Systems

The Phoenix VAL-MS 320 series is a 320V AC voltage-class surge protector (SPD) designed for industrial low-voltage power distribution, automation control, and terminal device overvoltage protection, with optional configurations (1+1/2/3/3+0/3+1/4-channel) and special functions (FM remote monitoring, UD universal design, ST screw terminals). The included VAL-MS 275/20 VF ST CRW is a 275V specialized model for compact, quick-wiring scenarios. This guide organizes part number-model correspondence, core parameters, and scenario recommendations to simplify SPD selection for different industrial systems.

I. Core Advantages of the VAL-MS 320/275 Series

1. Wide configuration coverage: Supports single-phase (1+1), dual-channel (2), three-phase (3/3+0), and three-phase four-wire (3+1/4) systems, adapting to diverse industrial power architectures.
2. Flexible functional extensions:
   • FM: Built-in remote monitoring contact for fault status feedback (critical for unattended systems);
   • UD: Universal design for multi-wiring compatibility (screw/spring terminals);
   • ST: Screw terminals for secure, vibration-resistant connections;
   • VF: Fork terminals for quick batch wiring (275V model exclusive).
3. Industrial-grade reliability: IP20 protection, -40°C to +85°C operating temperature, and high surge current tolerance (20kA for 275V model), suitable for harsh factory environments.
4. System-matched voltage: 320V for standard low-voltage industrial systems, 275V for special low-voltage equipment (e.g., precision sensors, compact control modules).

II. Complete Product Classification & Parameter Table

1. VAL-MS 320 Series (320V AC, Mainstream Configurations)

Classified by wiring configuration and special functions, covering single-phase to three-phase four-wire systems for different power and signal circuits.

2. VAL-MS 275 Series (Specialized Low-Voltage Model)

Single-model with compact, quick-wiring features for 275V precision equipment.

III. VAL-MS 320/275 Series Nomenclature Decoding

VAL-MS [Voltage]/[Configuration]-[Special Feature]

• Voltage: 320/275 → Adapted system voltage (320V for standard low-voltage, 275V for special precision systems).
• Configuration:
  • 1+1 = Single-phase (L+PE, independent ground);
  • 2 = Dual-channel single-phase (two independent circuits);
  • 3 = Three-phase three-wire (no neutral/ground sharing);
  • 3+0 = Three-phase three-wire (L1-L3+PEN, shared neutral/ground);
  • 3+1 = Three-phase four-wire (L1-L3+N+PE, separate neutral/ground);
  • 4 = Four-channel (multi-circuit hybrid);
  • Omitted = Universal (compatible with single/three-phase basic wiring).
• Special Feature:
  • FM = Remote monitoring contact (for fault status signal output);
  • UD = Universal design (supports screw/spring terminal wiring);
  • ST = Screw terminals (secure, anti-vibration connection);
  • VF = Fork terminals (quick batch wiring, 275V model exclusive);
  • CRW = Compact width (space-saving for narrow cabinets, 275V model exclusive);
  • 20 = Discharge current rating (20kA, 275V model exclusive).

IV. 3-Step Quick Selection Technique

Step 1: Confirm System Voltage

• Standard 320V low-voltage industrial systems: Select VAL-MS 320 series (all models except 2908059) for general power distribution and automation equipment.
• 275V precision/special equipment: Choose VAL-MS 275/20 VF ST CRW (2908059) for compact, quick-wiring protection.

Step 2: Match Configuration to Grounding System

• Single-phase (L+N/PE):
  • Independent ground (L+PE) → 1+1 configuration (e.g., 2804380 VAL-MS 320/1+1);
  • Dual-circuit single-phase → 2-channel configuration (5772223 VAL-MS 320/2);
  • General single-phase → Universal models (5772168 VAL-MS 320).
• Three-phase systems:
  • Three-phase three-wire (PEN shared) → 3+0 configuration (2920230 VAL-MS 320/3+0);
  • Three-phase three-wire (independent) → 3-channel configuration (5772304 VAL-MS 320/3);
  • Three-phase four-wire (N/PE separate) → 3+1 configuration (2859178 VAL-MS 320/3+1);
  • Multi-circuit hybrid → 4-channel configuration (5772388 VAL-MS 320/4-FM).

Step 3: Select Special Functions Based on Scenario

• Critical/unattended systems: Add FM suffix (e.g., 2859181 VAL-MS 320/3+1/FM) for remote fault monitoring.
• Mixed-terminal wiring: Choose UD (universal design) models (2858315 VAL-MS 320-UD ST) for screw/spring compatibility.
• Vibration-prone environments: Select ST (screw terminal) models (2838843 VAL-MS 320 ST) for secure connections.
• Batch quick-wiring (275V): Opt for VF (fork terminal) model (2908059 VAL-MS 275/20 VF ST CRW) to reduce installation time.
• Space-constrained cabinets (275V): Use CRW (compact width) model (2908059) to save 30% cabinet space.

V. Recommended Industry-Scenario Combinations

VI. Selection Pitfall Avoidance Guide

1. Voltage mismatch: 275V precision equipment using 320V SPD → Select 2908059 VAL-MS 275/20 VF ST CRW to avoid over/undervoltage damage.
2. Configuration error: Three-phase four-wire (N/PE separate) using 3+0 SPD → Choose 3+1 models (e.g., 2859178) to ensure independent neutral/ground protection.
3. Monitoring function neglect: Critical unattended systems using non-FM models → Add FM suffix (e.g., 2920243) for fault early warning and remote maintenance.
4. Terminal type error: Batch quick-wiring projects using ST screw terminals (320V) → For 275V systems, use VF fork terminals (2908059); for 320V, match UD universal models (2858315) for mixed wiring.
5. Space constraint oversight: Narrow cabinets using standard-width SPD → Select CRW compact model (2908059) for 275V systems, or slim 320V universal models (5772168) for 320V systems.
6. Grounding system mismatch: PEN-shared systems using 3+1 SPD → Opt for 3+0 models (2920230) to match the grounding architecture and avoid protection failure.

Conclusion: Select the Right VAL-MS SPD for 320V/275V System Protection

The Phoenix VAL-MS 320/275 series provides targeted overvoltage protection for low-voltage industrial systems, with diverse configurations for single-phase/three-phase circuits and flexible functions for monitoring, wiring, and space constraints.