UE LDP1WC250P-16

Technical & Performance Specifications

1. Electrical Surge Parameters
   • Maximum Continuous Operating Voltage Uc: 250 VAC, 50/60 Hz
   • Nominal Discharge Current In (8/20 μs waveform): 16 kA per phase
   • Lightning Impulse Current Iimp (10/350 μs waveform): 7.5 kA L-N path, 12.5 kA N-PE path
   • Voltage Protection Level Up: L-N ≤1.2 kV; N-PE ≤1.5 kV
   • Surge Response Time: L-N path ≤25 ns; N-PE ground path ≤100 ns
   • Temporary Overvoltage Withstand: 335 VAC for 5 seconds L-N; 1200 VAC for 200 ms N-PE
   • Follow Current Interrupt Rating: 100 A N-PE path
   • Residual Leakage Current Ipe: <0.1 mA under normal operating voltage
   • Short-Circuit Current Withstand Rating: 25 kArms with matching upstream backup fuse
2. Remote Alarm Function (WC Variant)
   • Dry Contact Alarm Output: SPDT form-C isolated contact, 1 A @ 30 VDC load capacity
   • Contact Trigger Condition: Internal varistor degradation, end-of-life cartridge failure
3. Physical & Environmental Data
   • Mounting Standard: 35 mm industry standard DIN rail mounting base
   • Cartridge Design: Tool-free pluggable replacement module without disconnecting base wiring
   • Status Indicator: Front panel visual color window (Green = Healthy; Red = Failed/End-of-Life)
   • Operating Temperature Range: -40°C ~ +70°C cabinet ambient
   • Storage Temperature: -40°C ~ +80°C
   • Compliance Standards: IEC/EN 61643-11 Type 1+2 SPD, UL1449 5th Edition, CE RoHS certified
4. Mechanical Dimensions
   • Base Module Width: 36 mm single DIN rail module width
   • Total Assembly Weight: 125 g

Function Features

• Combined Type 1+2 dual-stage surge suppression simultaneously blocking direct lightning impulse and indirect switching transient surges
• Pluggable cartridge design allows rapid replacement of degraded protection elements without rewiring cabinet power circuits
• Dual fault notification system: local visual color indicator + remote dry contact alarm output wired to PLC input for centralized monitoring
• Ultra-fast nanosecond-level response time to suppress steep-front transient voltage spikes before sensitive control hardware damage occurs
• Low residual leakage current under normal operating voltage eliminating unnecessary earth leakage circuit breaker tripping
• Integrated thermal disconnection safety circuit automatically isolates failed varistor elements to prevent cabinet fire risk
• Short-lead low-impedance internal layout maximizing surge energy absorption efficiency
• Wide operating temperature range suitable for outdoor control cabinets and high-temperature industrial plant environments
• Full compliance with global industrial surge protection standards for factory automation, power and railway control systems

Working Principle

Material & Structural Composition

• DIN Rail Base Housing: Flame-retardant V0 grade PA66 plastic with built-in copper PE bus bar
• Pluggable Protection Cartridge: Sealed ABS plastic enclosure encapsulating MOV varistor stacks and spark gap discharge elements
• Electrical Terminals: Nickel-plated copper screw terminals accepting 0.5–4 mm² solid/stranded wiring
• Thermal Disconnect Element: Bimetallic thermal trip strip integrated with varistor assembly
• Alarm Contact Switch: Miniature silver contact SPDT relay module for WC remote signal output
• Status Indicator Window: Transparent polycarbonate UV-resistant front viewing panel

Installation Requirements

1. Mount horizontally on standard 35 mm top-hat DIN rail inside upstream section of industrial control cabinet (closest to mains power inlet)
2. Maintain ultra-short wiring routing between SPD terminals and main cabinet PE bus bar; maximum wire length limited to 0.5 m
3. Install matched backup overcurrent fuse upstream of SPD per short-circuit withstand rating (25 kArms specified fuse size)
4. Remote alarm dry contact wiring must use separate shielded signal cable routed away from high-current power wiring
5. Cabinet PE bus bar must connect to facility low-resistance protective earth grid (<4 Ω earth resistance)
6. Cartridge insertion must fully lock into DIN base until audible click confirms contact engagement
7. Avoid mounting adjacent to high-power variable-frequency drives generating continuous electromagnetic noise

Application Scenarios

• PLC and industrial controller 220/240 VAC power supply surge protection
• Factory floor sensor, encoder and low-power actuator control circuit protection
• Railway wayside signal cabinet auxiliary power surge suppression
• Solar PV auxiliary control cabinet AC circuit lightning protection
• Outdoor pumping station, water treatment field control cabinet power protection
• Petrochemical plant instrument control panel transient voltage mitigation

Usage Precautions

• Do not operate SPD without upstream backup fuse installed; risk of internal overheating and cabinet fire during severe surge events
• Replace cartridge immediately once front indicator window turns red; degraded unit offers zero surge protection
• Remote alarm contact load must not exceed 1 A @ 30 VDC rating to avoid contact welding failure
• Regular visual inspection every 6 months for status indicator color and terminal screw tightness
• Do not daisy-chain multiple SPD units in series; install single dedicated unit at each cabinet mains inlet
• Ensure PE earth wiring is never disconnected while cabinet power is live
• Cartridge replacement must be performed with upstream power supply fully isolated and locked out