WTH-20/D/R/2P Series
www.watchfuleyesolutions.com Surge Protective Device for AC Power Supply System

Paperless Datasheet
Going green and protecting environment is manufacturers' responsibility. WatchfulEye products have the links of downloading data sheet on its enclosure:

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.

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) <5ns
Leakage Current (at 75%U1mA) <20μA
Thermal Protection YES
Protection Rating (IP Code) IP 20
Short Circuit Current Ratings (SCCR) 25kA 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 36mm (2TE)
Housing Material Thermoplastic (UL94 V-0)
Housing Design Modular design
Net Weight Per Unit 0.48Lb (219g)
Package Dimension (W×H×D) 1.4"×3.9"×2.7" (36mm×99mm×69mm)
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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Ordering Information
Model Uc(AC/DC) Up Ures Ordering code
WTH-20/D/R/2P-75 75/100V 0.8kV 0.6kV US120111
WTH-20/D/R/2P-115 115/150V 1.0kV 0.7kV US120112
WTH-20/D/R/2P-150 150/200V 1.1kV 0.8kV US120113
WTH-20/D/R/2P-275 275/350V 1.3kV 1.0kV US120114
WTH-20/D/R/2P-320 320/400V 1.4kV 1.1kV US120115
WTH-20/D/R/2P-385 385/500V 1.5kV 1.2kV US120116
WTH-20/D/R/2P-420 420/600V 1.7kV 1.4kV US120117
WTH-20/D/R/2P-550 550/700V 2.0kV 1.8kV US120118
WTH-20/D/R/2P-690 690/800V 2.4kV 2.1kV US120119
WTH-20/D/R/2P-885 885/1000V 2.7kV 2.2kV US120454
※ Frequency: 50/60Hz (AC Power)
※ How to Name Models on UL Listing: http://datasheet.watchfuleyesolutions.com/UL.html

Common Terms and Definitions
Maximum Continuous Operating Voltage (Uc or MCOV):
Maximum r.m.s. voltage, which may be continuously applied to the SPD's mode of protection.

Nominal Discharge Current for Class II Test (In):
crest value of the current through the SPD having a current waveshape of 8/20.

Maximum Discharge Current (Imax):
Crest value of a current through the SPD having an 8/20 waveshape and magnitude according to the manufacturers specification. Imax is equal to or greater than In.

Open Circuit Voltage (Uoc):
Open circuit voltage of the combination wave generator at the point of connection of the device under test.

Voltage Protection Level (Up):
Maximum voltage to be expected at the SPD terminals due to an impulse stress with defined voltage steepness and an impulse stress with a discharge current with given amplitude and waveshape.

Residual Voltage (Ures):
Crest value of voltage that appears between the terminals of an SPD due to the passage of discharge current.


AC Network Connection Diagram (including some uncommon systems)