Design, Specifications are subject to change without notice. Ask factory for technical specifications before purchase and/or use.
Whenever a doubt about safety arises from this product, please inform us immediately for technical consultation without fail.
Thermal Cutoffs (TCO)
●Design Applications
opening or opening delay.
·
operate while being used.
·
holding temperature.
after the TCO operates.
·
being exceeded, it may not cut off the circuit.
If the temperatures transferred to the main body and to the lead wires(terminals) are largely different from
ished equipment.
✽
(1)
2 2 3 2 2
(2)
✽ment, etc.
●Instruction
7. Forming and Cutting
(axial / radial type) or body (thin type). The TCO seals (axial / radial type) shall not be grasped with any
2) The lead wires and terminals shall not be nicked, fractured or bumed.
The body and/or seals must not be damaged, burned or overheated.
twisting or the like.
Safety Precautions (Handling Precautions)
1. Use TCO within their specified temperature and electrical ratings.
in the individual specification.
When the TCO is continuously used at the temperature close to the functioning temperature, the TCO may
When the TCO is continuously used at the temperature higher than the maximum operation temperature,the
TCO may be degraded and may not operate normally at the specified temperature
2) The holding temperature is defined as the highest temperature at which the TCO is activated continuously
3) Equipment should be designed so that its over shoot does not exceed the maximum temperature limit
at the rated current for 168 hours. The TCO can not be used over 168 hours exceeding the
4) If the TCO is activated by voltage higher than the rated voltage or current higher than the rated current, the
operation will result in an abnormality of appearance(crack on body) and insufficient insulation.
When TCO is operated in an abnormal mode while the rated voltage and/or the rated current
6) The TCO cannot be used as a current sensitive fuse.
1) Tests should be repeated for the finished equipment to confirm that the TCO does operate
close to the heat source as possible and the place where the TCO is evenly heated.
as expected.
2) To improve thermal response of the TCO, put the main body of the TCO and the lead wires(terminals) as
of the fusible alloy or lead wires, or damage to the main body may result.
When sealing the overall TCO with resin, test repeatedly to confirm normal operation of the TCO in the fin-
5. Avoid dipping the equipment with the TCO into varnish or chemical or organic solvent and then drying it.
The solvent or the varnish may corrode the body and/or lead wires (terminals) of the TCO.
6. Do not use under the following environments.
2) Under direct sunlight and outdoor and dusty atmospheres
before production use.
In environments with high static electricity and/or strong electromagnetic waves.
Do not use the TCO in aerospace equipment, atomic energy equipment, military weapons, life saving equip-
tools or holders. Terminals of thin type TCO are to be grasped before they are bent. (See Fig.1)
3) It is recommended that experimental assembly trials, should be done so that it can be
verified that manufacturing procedures will not exceed the maximum tested "pull" and "push" forces of 20 N
1) Use the TCO under an ambient temperature of not more than the maximum operating temperature specified
Using the TCO under a higher temperature than the maximum operating temperature may cause premature
TCO produces excessive heat, resulting in premature opening. The arc generated at this condition of
5) Where transient overload is expected to be applied, repeat the tests under the worst conditions.
2. To fully use the function of the TCO, a suitable TCO for each equipment application must be selected.
each other, improper operation can be expected, causing arcing and deterioration of insulation.
3. Avoid application of excessive vibration and mechanical stress to the TCO. Otherwise, failure
4. When sealing the TCO with resin, select a resin that does not corrode the seals or the lead wires(terminals).
1) In liquids such as water, oil, chemical and organic solvents
3) In places where water condensation occurs.
Use in the following environments may affect the performance of the TCO; Verify performance and reliability
In places full of corrosive gases such as sea breeze, Cl , H S, NH , SO and NO
1) Lead wires(terminals) are to be bent or cut at least 3 mm away from the TCO seals to avoid damaging the TCO.
(MT series:10 N, MS series: 5 N) and 5 N respectively on the lead wires (terminals), or induce excessive