Quality Control Process

At THOR, quality control is built into each manufacturing stage — from 100% data testing of incoming MOV chips, through in-process assembly checks, to outgoing inspection before shipment. Destructive and impulse tests on finished SPDs are performed on samples according to the applicable inspection plan.

01
IQC Stage Incoming Quality Control
02
IPQC Stage In-Process Assembly
03
OQC Stage Outgoing Quality Control

Inspection & Verification at Three Key Stages

THOR applies rigorous quality checks across our production lines, ensuring potential issues are identified and mitigated before they reach the next step.

01

Incoming Quality Control (IQC)

Every incoming component is inspected and verified before entering the production line. Key checks focus on material quality, electrical characteristics and dimensional consistency.

1. Metal Parts
Incoming metal parts inspection for SPD manufacturing Incoming Metal Parts Inspection

Checks incoming metal components before production.

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Salt spray testing of metal components Salt Spray Testing

Evaluates corrosion resistance of the tested metal components.

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Spectral testing of metal material Spectral Testing

Verifies the material composition of selected metal parts.

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Dimensional inspection of metal parts Dimensional Inspection

Checks component dimensions against production requirements.

2. Plastic Components
Incoming plastic component inspection Incoming Plastic Components

Checks incoming molded components before assembly.

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Flame retardancy testing of plastic components Flame Retardancy Testing

Verifies the required flame-retardant performance of tested materials.

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Dimensional inspection of plastic components Dimensional Inspection

Checks dimensions and fit before assembly.

3. PCB Boards
Incoming PCB inspection Incoming PCB Inspection

Checks incoming boards before they enter assembly.

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PCB circuit continuity inspection Circuit Continuity

Checks electrical continuity of the relevant circuit paths.

4. Varistors (MOV Chips)
Incoming MOV inspection for SPD manufacturing Incoming MOV Inspection

Incoming MOV batches are sampled and tested before assembly.

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MOV voltage testing MOV Voltage Test

Verifies the voltage characteristics of the tested MOVs.

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MOV chip dimensional inspection Dimensional Inspection

Checks MOV dimensions for production consistency.

02

In-Process Quality Control (IPQC)

Assembly operations are monitored throughout production, with in-process testing used to maintain manufacturing consistency before final integration.

Line A: Base & Signaling Circuit Assembly

Base Assembly

Base housing assembly for surge protection device Base Housing Assembly
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SPD base assembly Base Assembly

Signaling Circuit

PCB soldering during SPD assembly PCB Soldering
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Continuity testing during SPD assembly Continuity Testing
↓ Two assembly tracks merge here ↓
Integrated base assembly Integrated Base Assembly
Line B: Independent MOV Assembly
MOV module soldering and assembly MOV Module Assembly
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MOV voltage verification during assembly Voltage Verification

100% voltage verification is performed on every MOV module before final assembly.

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MOV chip core assembly Chip/Core Assembly
Final Assembly
Final merging of SPD base assembly and varistor core module Final Assembly of Base & MOV Protection Module

Completes the final assembly of the base and MOV protection module into a finished surge protection device.

03

Outgoing Quality Control (OQC)

Destructive and impulse tests are carried out on finished-product samples according to the applicable inspection plan.

Quality Inspection & Dispatch
Sampling inspection including destructive and impulse tests
1. Sampling Inspection

Includes the applicable destructive and impulse tests used for outgoing quality verification.

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Professional SPD packaging and barcoding
2. Packaging & Labeling

Finished products are prepared, identified and packaged for shipment.

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Global shipping of surge protection devices
3. Global Shipping

Approved products are prepared for delivery to customers and projects worldwide.

Explore THOR
Surge Protection
Devices

Explore our AC, DC, PV and signal SPD ranges, with model-specific ratings, documents and available configurations.

AC Surge Protection Devices

Type 1, Type 2, and Type 1+2 surge protectors engineered for compliant low-voltage power distribution systems.

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DC Surge Protection Devices

Industrial DC surge protective devices optimized for telecom base stations, battery storage, and control circuits.

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PV Surge Protection Devices

Certified DC SPDs covering 600V to 1500V DC working voltage for utility-scale and rooftop solar power systems.

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Signal Surge Protection Devices

High-frequency, low-insertion-loss protection for RJ45/PoE, RS485, coaxial, and critical industrial data lines.

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Looking for OEM or customized SPD manufacturing?

Explore THOR's complete in-house manufacturing capabilities, automated laser marking lines, and flexible sample options for private-label brands.

Explore OEM Capabilities
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