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Model & Ordering Code (3P Mode)

Model Ordering Code MCOV/Uc Up Ures UPC/EAN Code
WTH-40/C/3P-PV200 US120397 200Vdcpv 1.7kV 1.2kV (0) 811914032076
WTH-40/C/3P-PV400 US120398 400Vdcpv 2.2kV 1.5kV (0) 811914032083
WTH-40/C/3P-PV600 US120334 600Vdcpv 2.5kV 1.9kV (0) 811914032090
WTH-40/C/3P-PV800 US120335 800Vdcpv 3.2kV 2.5kV (0) 811914032106
WTH-40/C/3P-PV1000 US120330 1000Vpvdc 3.4kV 2.8kV (0) 811914032113
WTH-40/C/3P-PV1000G US120330G 1000Vpvdc 3.4kV 2.8kV with GDT, Iimp:15kA
WTH-40/C/3P-PV1200 US120331 1200Vpvdc 3.6kV 3.0kV (0) 811914032120
WTH-40/C/3P-PV1600 US120395 1600Vpvdc 4.6kV 3.6kV (0) 811914032137
WTH-40/C/3P-PV2000 US120396 2000Vpvdc 5.7kV 4.6kV (0) 811914032144

Certificates of Products - Page 01 - Back to TOP -

Model & Ordering Code (1P/2P Mode)

Model Ordering Code MCOV/Uc Up Ures UPC/EAN Code
WTH-40/C/1P-PV100 US120339 100Vdcpv 1.3kV 0.8kV (0) 811914032151
WTH-40/C/2P-PV100 US120333 (0) 811914032168
WTH-40/C/1P-PV200 US120338 200Vdcpv 1.5kV 1.0kV (0) 811914032175
WTH-40/C/2P-PV200 US120337 (0) 811914032182
WTH-40/C/1P-PV300 US120403 300Vdcpv 1.7kV 1.2kV (0) 811914032199
WTH-40/C/2P-PV300 US120393 (0) 811914032205
WTH-40/C/1P-PV400 US120404 400Vdcpv 1.9kV 1.4kV (0) 811914032212
WTH-40/C/2P-PV400 US120394 (0) 811914032229
WTH-40/C/1P-PV500 US120386 500Vdcpv 2.2kV 1.6 kV (0) 811914032236
WTH-40/C/2P-PV500 US120385 (0) 811914032243
WTH-40/C/1P-PV600 US120336 600Vdcpv 2.4kV 1.8kV (0) 811914032250
WTH-40/C/2P-PV600 US120332 (0) 811914032267
WTH-40/C/1P-PV800 US120402 800Vdcpv 2.8kV 2.2kV (0) 811914032274
WTH-40/C/2P-PV800 US120392 (0) 811914032281
WTH-40/C/1P-PV1000 US120401 1000Vpvdc 3.4kV 2.8kV (0) 811914032298
WTH-40/C/2P-PV1000 US120391 (0) 811914032304 - Page 02 - Back to TOP -

In accordance with: IEC/EN61643-11 - Class II and UL1449 Type 4 Location
BatteryManagement System, Suitable for off-grid PV system or grid-connected system
Location of use: BatteryManagement System, DC System, DCpv System, Photovoltaic Combiner Box, Photovoltaic Power Supply Box
Plug-in module and separate base design enables convenient maintenance.
Internal thermal disconnect devices help ensure safe or at end-of-life
WTH-40/C DC & PV Series Technical Data
Requirement Class to IEC/EN61643-11 Class II
IEEE Category Rating B & A
Nominal Discharge Current (In) 20kA
Max. Discharge Current (Imax) 40kA
Protection Modes DC+/PE, DC-/PE, DC+/DC-
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 >80A) 80A gL (circuit-breaker: <40A)
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
Housing Material Thermoplastic (UL94 V-0)
Housing Design Modular design - Page 03 - Back to TOP -

Surge Protection Connection Diagram

Fault Indication (same indication in 1P/2P/3P models) - Page 04 - Back to TOP -

Remote Contacts (Dry Contacts)
1: COM (Common)
2: NC (Normally Close)
3: NO (Normally Open)

Contact Ratings 125VAC/3A, 250VAC/1.5A
Terminal Cross Section Max. 1.5mm²
Stripping Length Contacts 0.25 inches (6-7mm)
Remote Terminal Torque 0.25Nm - Page 05 - Back to TOP -

1P mode
Single modules can be combined with a bus bar in multiple combination methods.

Three features of 3P mode strengthening protection
A: The isolated barrier between two modules
B: 3mm-wide gap between two modules
1. Increase creepage distance
2. Increase the capacity of insulation isolation and make the connection more secure
3. More important for the application with MCOV (Uc) higher than 800Vdc

C: Two MOVs are connected in series between each line to make the conduction voltage of common mode and differential mode surge protection achieve the best balance, and the Up value between all lines is kept on a horizontal level. - Page 06 - Back to TOP -

Dimensions - Page 07 - Back to TOP -

Common Terms and Definitions
1. Normal operating voltage rating (Un)
2. Maximum Continuous Operating Voltage (Uc/MCOV):
Maximum r.m.s. voltage, which may be continuously applied to the surge protective device's mode of protection.
3. Nominal Discharge Current for Class II Test (In):
crest value of the current through the surge protective device having a current waveshape of 8/20μs.
4. Maximum Discharge Current (Imax):
Crest value of a current through the surge protective device having an 8/20μs waveshape and magnitude according to the manufacturers specification. Imax is equal to or greater than In.
5. Voltage Protection Level (Up):
Maximum voltage to be expected at the surge protective device terminals due to an impulse stress with defined voltage steepness and an impulse stress with a discharge current with given amplitude and waveshape.
6. Residual Voltage (Ures):
Crest value of voltage that appears between the terminals of an surge protective device due to the passage of discharge current.
7. IEEE 62.41
CATEGORY C: outdoor overhead lines, service entrance (most severe)
CATEGORY B: major feeder, short branch circuits, service panel (indoor)
CATEGORY A: long branch circuits, receptacles (indoor) (least severe)

How to choose a suitable Uc(MCOV) value
Note: Uc >1.15Un
The relationship between two parameters Uc and Up of a surge protective device is proportional.
If Uc is small, the value of Up is also small; surge protective devices with smaller Up can provide better surge protection.
Whether to choose smaller Uc depends on the voltage stability of the grid.
If you choose surge protective devices with smaller Uc for the grid with instable voltage, the surge protective devices will frequently work while the grid voltage fluctuates, resulting in shortening surge protective device's product life.
If you choose larger Uc, and the value of Up is accordingly large, the surge protective efficiency will not be so fine.
If you are unsure of the voltage stability of the grid,
it is suggested to calculate MCOV(Uc) using the following formula: √ 2  Un < Uc < √ 3 Un

DC System (Un) MCOV(Uc), DC+/DC- DC System (Un) MCOV(Uc), DC+/DC-
70Vdc 100Vdc 560Vdc 800Vdc
140Vdc 200Vdc 700Vdc 1000Vdc
210Vdc 300Vdc 840Vdc 1200Vdc
280Vdc 400Vdc 1120Vdc 1600Vdc
350Vdc 500Vdc 1400Vdc 2000Vdc
420Vdc 600Vdc - Page 08 - Back to TOP -

2P Mode Connection Diagram

3P Mode Difference mode & Common mode Connection Diagram

Common mode:DC+ to PE, DC- to PE surge protection
Difference mode:DC+ to DC- surge protection - Page 09 - Back to TOP -

Selection of back-up fuse

Selection of back-up circuit-breaker - Page 10 - Back to TOP -

Application - Page 11 - Back to TOP -

FAQ & Help
1. What should I do if I can't find the paper manual in the product packaging?
Watchful Eye products is committed to going green with paperless data sheets. On the side of each product enclosure is an engraved link with URL for downloading paperless data sheet and QR code of the website. If you need the paper data sheet, you can open the link and print the data sheet by yourself.

2. The advantages of fault indication windows?
If surge protection fails, the fault indication windows will turn red, thus it can be seen intuitively, and the surge protective device can be replaced in time to avoid damage to the equipment caused by a second surge.

3. What instruments can be used to test whether its surge protection function is normal or not?
Test with a Watchful Eye surge protector tester

4. Can you list more applications?
DC System, DCpv System, Photovoltaic Combiner Box, Photovoltaic Power Supply Box - Page 12 - Back to TOP -

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After-sale Services
Watchful Eye provides a 5-year quality warranty globally.

I have a question - Page 13 - Back to TOP -