WTH-20/D/R/4P Wi-Fi 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 III and UL1449 Type 4 Location
Location of use: branch sub-distribution boards
Plug-in module and separate base design enables convenient maintenance.
Network with Wi-Fi, smart remote monitoring

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 90mm (5TE)
Housing Material Thermoplastic (UL94 V-0)
Housing Design Modular design
Net Weight Per Unit 1.23Lb (560g)
Package Dimension (W×H×D) 3.6"×3.6"×2.7" (90mm×90mm×69mm)
Smart Remote Monitoring YES
Surge Count 0-999
Network Connection Wi-Fi
SPD Module Monitoring Built-in Integration

Smart Detector Connection Guide
1. Connect the induction coil of surge counter to the 2-port pluggable terminal block (no direction). Hitch the induction loop to the earthing line.
2. Connect USB line (5VDC) to micro usb port of surge counter, and then LED is on.
Connection Diagram
Fault Indication
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Ordering Information
Model Uc(AC/DC) Up Ures Ordering code
WTH-20/D/R/4P-150 Wi-Fi 150/200V 1.1kV 0.8kV USW120153
WTH-20/D/R/4P-275 Wi-Fi 275/350V 1.3kV 1.0kV USW120154
WTH-20/D/R/4P-320 Wi-Fi 320/400V 1.4kV 1.1kV USW120155
WTH-20/D/R/4P-385 Wi-Fi 385/500V 1.5kV 1.2kV USW120156
WTH-20/D/R/4P-420 Wi-Fi 420/600V 1.7kV 1.4kV USW120157
WTH-20/D/R/4P-885 Wi-Fi 885/1000V 2.7kV 2.2kV USW120458
※ 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)


USW Series Description: http://datasheet.watchfuleyesolutions.com/USW.html
GreenSPD.com Cloud Service: http://datasheet.watchfuleyesolutions.com/Cloud.html