Xiamen SET Electronics Co., Ltd.

The Gas Discharge Tube(GDT) is a protective device which is filled with certain proportion of noble gas, or mixed gas or other discharge media in the space between metal electrodes and metalized ceramics,and then sealed at high temperature to form a single-gap or multi-gap switch type protective device.When the protected circuit or equipment suffers to surge, GDT will change from high impedance state to low impedance state and release the surge energy to reduce the residual voltage of the circuit, and then protect the equipment or humanbody from the hazard of transient overvoltage.

SETsafe | SETfuse GDT products have a voltage range of 70 to 4500 V and a surge current (at 8 / 20 μs) range of 0.5 to 200 kA. It is widely used in the overvoltage protection of signals, power supplies, and various ports; safety certificates include UL, cUL, TUV, and it also meets RoHS & REACH requirements.

V_s

D.C. Spark-over Voltage

The voltage at which the GDT sparks over with slowly increasing d.c. voltage.

— (IEC 61643-311)

V

Impulse Spark-over Voltage

The highest Voltage which appears across the terminals of a GDT in the period between the application of an impulse of given wave-shape and the time when current begins to flow.

— (ITU-T K.12)

V_a

Arc Voltage

Voltage drop across the GDT during arc current flow.

— (IEC 61643-311)

V_gl

Glow Voltage

The peak value of the voltage drop across the GDT when a glow-current is flowing, It is sometimes called the glow mode voltage.  

— (ITU-T K.12)

8/20 μs

8/20 Current Impulse

Current impulse with a nominal virtual front time of 8 µs and a nominal time to half-value of 20 µs.

— (IEC 61643-11)

1.2/50 μs

1.2/50 Voltage Impulse

Voltage impulse with a nominal virtual front time of 1.2 µs and a nominal time to half-value of 50 µs.

— (IEC 61643-11)

I

Alternating Discharge Current

The r.m.s. value of an approximately sinusoidal alternating current passing through the GDT.

— (ITU-T K.12)

I_n

Nominal Discharge Current

Crest value of the current through the GDT having a current waveshape of 8/20 µs.

— (IEC 61643-11)

I_max

Maximum Discharge Current

Crest value of a current through the GDT having an 8/20 µs waveshape and magnitude according to the manufacturers specification. I_max is equal to or greater than In.

— (IEC 61643-11)

Through Hole, Surface Mount

SMD, Axial, Radial

Street Lighting (Power Supply, N-PE Protection in AC Power)

Application SETsafe | SETfuse Product Series:

SE Series

SF Series

New Energy (WLAN xDSL, Power Supply, N-PE Protection in AC Power)

Application SETsafe | SETfuse Product Series:

SE Series

SC Series

Communication (WLAN xDSL, CATV, MDF, BTS(Base Station), Antenna and RF, N-PE Protection in AC Power)

Application SETsafe | SETfuse Product Series:

SX Series

SW Series

TZ Series

SE Series

SC Series

SPA Series

SPB Series

SPC Series

SPJ Series

SPI Series

Security Monitoring (WLAN xDSL)

Application SETsafe | SETfuse Product Series:

SX Series

TZ Series

Medical (WLAN xDSL)

Application SETsafe | SETfuse Product Series:

SN Series

TZ Series

Home Appliances (Power Supply, Consumer Electronics)

Application SETsafe | SETfuse Product Series:

SE Series

SF Series

SETsafe | SETfuse Quality Policy

Provide Industry-Leading Products

Raw-materials Supplier

Select critical raw materials: Must be from a manufacturer with quality management system (ISO9001, IATF16949) certification.

Annual or Quarterly Audits.

IQC (Incoming Quality Check)

AQL(MIL-STD-105E), Dimensions, Function, Visual Inspection, RoHS & REACH Test.

Document

Formulate corresponding incoming inspection specifications (01-QA-06-xxx) for each key material according to design data such as material technical indicators.

Testing Equipment and Tools

Projector, Tool Microscope, Salt Spray Tester, Universal Material Testing Machine, Spectrum Analyzer, etc.

Manufacturing Process

Online Inspection and Testing (Function 100% Automatic Testing).

Document

Process Flow Chart.

Failure Mode and Effects Analysis (FMEA).

Quality Control Flow Chart (QCFC).

Standard Inspection Procedure (SIP).

Work Instruction (WI).

Online Testing and Inspection

D.C. Spark-over Voltage Test (@100V/s) (100% Automatic Testing).

Insulation resistance Test system (100% Automatic Testing).

etc.

IPQC (In Process Quality Control) Inspection

AQL(MIL-STD-105E), Dimensions Inspection, Function Test, Visual Inspection.

FQC ( Final Quality Control)

AQL(MIL-STD-105E), Dimensions Inspection, Function Test, Visual Inspection, RoHS & REACH Test.

Reliability Test

Test specification (01-TE-01-xxx).

Including 17 items of appearance requirements, Electrical Performance, Mechanical Performance, Soldering Performance and Environmental test. e.g.

D.C. Spark-over Voltage Test（@100V/s）

Insulation resistance Test.

Impulse Discharge Current Test.

Low Temperature Test

High Temperature Test

etc.

OQC (Outgoing Quality Control)

AQL(MIL-STD-105E), Packaging, Labeling, Quantity Inspection.

Agency

Agency (Safety Certificate) Annual, Quarterly Audits.

Management System

ISO9001, (TUV approved and issued certificate).

ISO14001, ISO45001, etc.

Click to view the certificate

Environmental

RoHS & REACH Compliant.

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Usage

1. Do not operate GDT in power supply networks, whose maximum operation voltage exceeds the minimum spark-overvoltage of the GDT.

2. The GDT may become hot in the event of longer periods of current stress (burn risk). In the event of overload the connectors may fail or the component may be destroyed. 

3. If the contacts of GDT are defective, current load can cause sparks and loud noises.

4. When air pressure is from 55 kPa to 106 kPa. The relative altitude shall be +5000 m to –500 m. 

Replacement

The GDT is a non-repairable product for safety sake, please use equivalent GDT for replacement.

Storage

The packaged GDT shoud be placed in a dry, ventilted and non-corrosive environment.

Installation Position

Do not install the GDT in a touchable position.

Mechanical Stress

Do not take violent action such as knocking when assembling, to avoid product failure.

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SET

Gas Discharge Tube (GDT) Catalog

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