WTH-120/B/1P Series
www.watchfuleyesolutions.com Surge Protective Device for AC Power Supply System

Paperless Datasheet
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In accordance with: IEC 61643-1 - Class I and UL1449 Type 4 Location
Location of use: main sub-distribution boards
With three MOVs' protection at the same time, the module can realize Class I surge protection; in case that two of the indicator windows indicates red, it can still meet
Class II surge protection requirements.

WTH-120/B/1P Series
Model Uc(AC/DC) Up Ures Ordering code
WTH-120/B/1P-75 75/100V 1.5kV 0.6kV US120291
WTH-120/B/1P-115 115/150V 1.7kV 0.7kV US120292
WTH-120/B/1P-150 150/200V 1.8kV 0.8kV US120293
WTH-120/B/1P-275 275/350V 2.1kV 1.0kV US120294
WTH-120/B/1P-320 320/400V 2.2kV 1.1kV US120295
WTH-120/B/1P-385 385/500V 2.4kV 1.2kV US120296
WTH-120/B/1P-420 420/600V 2.5kV 1.4kV US120297
WTH-120/B/1P-550 550/700V 2.9kV 1.8kV US120298
WTH-120/B/1P-690 690/800V 3.2kV 2.1kV US120299
※ 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 I
IEEE Category Rating C & B
Nominal Discharge Current (In) 60kA
Max. Discharge Current (Imax) 120kA
Pulsed Current (Iimp) 15kA
Protection Modes L-PE, N-PE
Protective Element High Energy MOV
Follow Current (If) NO
Response Time (tA) <5ns
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 >160A) 160A gL (circuit-breaker: <100A)
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 35.8mm (2TE)
Housing Material Thermoplastic (UL94 V-0)
Housing Design Compact design
Net Weight Per Unit 0.46Lb (209g)
Package Dimension (W×H×D) 1.4"×3.6"×2.6" (35.8mm×90mm×66.5mm)
Remote Contacts NO
Contact Ratings 125VAC/3A, 250VAC/1.5A
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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