WTH-20/D/R/3P Series
www.watchfuleyesolutions.com Surge Protective Device for AC Power Supply System

In accordance with: IEC 61643-1 - Class III and UL1449 Type 4 Location
Location of use: branch sub-distribution boards
Plug-in module and separate base design enables convenient maintenance.

WTH-20/D/R/3P Series
Model Uc(AC/DC) Up Ures Ordering code
WTH-20/D/R/3P-75 75/100V 0.8kV 0.6kV US120371
WTH-20/D/R/3P-115 115/150V 1.0kV 0.7kV US120372
WTH-20/D/R/3P-150 150/200V 1.1kV 0.8kV US120373
WTH-20/D/R/3P-275 275/350V 1.3kV 1.0kV US120374
WTH-20/D/R/3P-320 320/400V 1.4kV 1.1kV US120375
WTH-20/D/R/3P-385 385/500V 1.5kV 1.2kV US120376
WTH-20/D/R/3P-420 420/600V 1.7kV 1.4kV US120377
WTH-20/D/R/3P-550 550/700V 2.0kV 1.8kV US120378
WTH-20/D/R/3P-690 690/800V 2.4kV 2.1kV US120379
※ Uc: Max. continuous operating voltage ※ Frequency: 50/60Hz (AC Power)
※ Up: Voltage protection level ※ Ures @6kV/3kA: Residual voltage

Technical Data
Requirement Class to IEC61643-1 Class III
IEEE Category Rating B & A
Nominal Discharge Current (In) 10kA
Max. Discharge Current (Imax) 20kA
Open circuit voltage (Uoc) 20kV
Protection Modes L-PE, N-PE
Protective Element MOV
Follow Current (If) NO
Response Time (tA) <25ns
Leakage Current (at 75%U1mA) <20μA
Thermal Protection YES
Protection Rating (IP Code) IP 20
Short Circuit Current Ratings (SCCR) 20kA rms
Max. Back-up Fuse (if mains >50A) 50A gL (circuit-breaker: <20A)
Surge Life at 3kA (8/20μs) >5000 events
Temperature Range - 40°F to 176°F (-40°C to 80°C)
Relative Humidity 0% to 95% noncondensing
Maximum Operating Altitude 10,000 feet (3000m)
Terminal Cross Section 35mm² (solid) / 25mm² (stranded)
Stripping Length Contacts 0.6inches (15mm)
Terminal Screw Torque Max. 3.5Nm
DIN Rail EN60715 35mm top-hat rail
Dimensions DIN 43880 62mm (3.5TE)
Housing Material Thermoplastic (UL94 V-0)
Housing Design Modular design
Net Weight Per Unit 0.73Lb (330g)
Package Dimension (W×H×D) 2.5"×3.9"×2.7" (62mm×98mm×69mm)
Remote Contacts NO
Contact Ratings AC:125V/1A
Terminal Cross Section Max. 1.5mm²
Stripping Length Contacts 0.25inches (6-7mm)
Remote Terminal Torque 0.25Nm

Connection Diagram
Fault Indication
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