Xiamen SET Electronics Co., Ltd.

SETsafe | SETfuse Organic Thermal-Link (OTCO) is a non-resettable protective device, functioning one time only. It mainly consists of metal case, spring, sliding contact and thermal pellet. The organic thermal pellet responds to abnormal temp. situation and triggers the cutoff function. 

SETsafe | SETfuse Organic Thermal-Link (OTCO) is widely used in electrical equipment to provide over temp. protection, it has wide range of operating temp., from 72 °C to 263 °C, rated current includes: 10 A, 15 A / 16 A. With UL, cUL, VDE, CCC, KC, PSE certificates, comply with RoHS and REACH.

TCO

Thermal-Link

A non-resettable device incorporating a THERMAL ELEMENT which will open a circuit once only when exposed for a sufficient length of time to a temp. in excess of that for which it has been designed.

OTCO

Organic Thermal-Link

Organic type Thermal-Link, Organic is the THERMAL ELEMENT.

T_f

Rated Functioning Temp.

The temp. of the Thermal-Link which causes it to change its state of conductivity with a detection current up to 10 mA as the only load.

Tolerance: T_f + 0 / - 10 K (GB/T 9816, EN60691, UL60691, KC60691).

Tolerance: T_f ± 7 K (J60691).

Fusing Temp.

The temp. of the Thermal-Link which causes it to change its state of conductivity is measured with silicone oil bath in which the temp. is increased at the rate of 0.5 K/min to 1 K/min, with a detection current up to 10 mA as the only load.

T_h

Holding Temp.

The max. temp. of the Thermal-Link at which it will not change its state of conductivity during 168 hours at the rated current.

T_m

Max. Temp. Limit

The temp. of the Thermal-Link stated by the manufacturer, up to which the mechanical and electrical properties of the Thermal-Link, having changed its state of conductivity, will not be impaired for a given time.

I_r

Rated Current

The current used to classify a Thermal-Link.

U_r

Rated Voltage

The voltage used to classify a Thermal-Link.

I_n

Nominal Discharge Current

Being able to withstand 15 peak currents of waveform 8/20 μs to test the product′s durability of withstanding pulse current

I_max

Max. Discharge Current

Being able to withstand 1 peak current of waveform 8/20 μs to test max. pulse current that the product can withstand.

Through Hole

Axial, Radial

Small Home Appliances 
 Electric Cooker, Bread Maker, Coffee Machine, Soymilk Machine, etc.

Comfort Home Appliances 
Washing Machine, Refrigerator, Air Conditioner, etc. 

Personal Care Appliances
Hair Dryer, Hair Straightener, Electric Iron, etc.

Commercial Appliances 
Printer, Scanner, Fax Machine, etc.

Automobile Field
Air Conditioner, Heated Seat, etc.

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

Resistance test system (100% Automatic Testing).

100% Visual Inspection.

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-01-1002-xxx)

Including 30 items of Mark Indelibility Performance, Mechanical Performance, Electrical Performance, Temperature Test, Soldering Performance Test，Environmental Test and Life Test. e.g.

Interrupting Current Test.

Dielectric Strength.

Maximum Temperature Limit Test.

Ageing 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.

SETsafe | SETfuse

Usage

1. Please use OTCO without exceeding the rated current and voltage.

2. Do not use the OTCO in environments out of the standard specifications, such as those containing sulfur dioxide gas, nitrogen oxide gas, ammonia gas or formic acid. It is also not suitable for using in high humidity environment or immersed in liquid.

Replacement

OTCO is a non-repairable product. For safety aspect, it shall be replaced by an equivalent OTCO from the same manufacturer, and mounted in the same way.

Storage

1. OTCO must be kept in a place with no sunshine and no corrosive gas, with temp. shall be -10°C ~ 35°C and humidity within 30% ~ 70%. The validity storage period of OTCO is 12 months after purchase.

2. The case and isolated lead of OTCO are silver-plated. Therefore, to avoid vulcanization, the OTCO shall not be kept around materials such as cardboard or rubber etc. which generate sulfurous acid gas.

Lead Process

1. If lead wires has to be bent, it is important not to apply excessive pressure to the root of the lead wires. The tensile forces applied to the lead wires shall not exceed 15.7N, and the thrust force applied to the lead wires shall not exceed 3.9N.

2. The lead wires should be bent at a distance 3 mm or above from the body of OTCO (see Fig.1).

3. To avoid damaging the OTCO, when bending lead wires, please use pincher or similar tools to fix the OTCO.

Installation

Selection of Installation Location

1. Do not locate the OTCO in a place where severe vibration always occurs.

2. The infrared thermography or multiple thermocouples should be considered to detect the ambient temp. under normal and  abnormal situation. The point that provides the biggest temp. rise between these two situations is the best installation location.

Make Sure the Temp. of Installation Location

1. The body of OTCO will generate heat as current flows through it, resulting the body temp. higher than ambient temp. The influence of temp. rise shall be considered in the design to determine the appropriate OTCO model.

2. It shall be ensured that the body temp. of OTCO and the ambient temp. at the installation position do not exceed the corresponding holding temp. Th.

3. The end product should be tested to ensure that potential abnormal conditions do not cause ambient temp. to exceed the Tm of the OTCO.

Mounting OTCO

1. OTCO can be installed by soldering, welding, riveting or crimping. During and after installation, please do not pull,  push or twist OTCO body or lead wires.

2. The connection point of the lead shall be less than 5 mm away from the OTCO body (see Fig.2).

3. Try to ensure that the body of the OTCO is evenly heated. If the temp. difference is inevitable, make sure that the sealing resin side be connected closer to the heat source.

Soldering

1. Soldering should be carried out according to below table. If secondary soldering is required, wait until the OTCO cools to room temp.

2. Soldering is not recommended for Thermal-Link with Tf ≤ 110°C, while non heating processes such as crimping and riveting are recommended.

3. In the process of soldering, cooling fixture should be used between soldering point and OTCO body (see Fig.2).

4. It is recommended to take X-ray after soldering, to confirm that the thermal pellet has no shrinkage after soldering.

TABLE 1: Max. Allowable Soldering Time for Different Length of Soldering Point from OTCO Body

Welding

1. Avoid welding current flowing into the inside of the OTCO. The welding current will cause the internal parts to be welded together, resulting in the failure function of OTCO.

2. During the welding process, the lead wires of the OTCO must be supported to avoid the damage of the OTCO.

3. In the process of welding, cooling fixture should be used between welding point and OTCO body (See Fig.2).

4. It is recommended to take X-ray after welding, to confirm that the thermal pellet has no shrinkage after welding.

Riveting or Crimping

1. Select materials with low resistivity (such as copper) for riveting and crimping.

2. Contact resistance shall be as small as possible. Large contact resistance will cause high temp. to make OTCO open in advance. 

3. It is better to crimp OTCO leads to stranded lead wires  rather than solid wires as the stranded wire may be crimped tighter and maintain better electrical contact during temp. cycling.

4. During the riveting and crimping process, ensure that the lead wires shall not be reversed, sealing resin shall not be destroyed. 

5. When the working temp. exceeds 150°C, soldering reinforcement it recommended after riveting and crimping.

The isolated lead is forbidden to contact OTCO body directly to avoid short circuit (See Fig.3).

SETsafe | SETfuse

SET

Thermal-Link(OTCO) Catalog

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