PTC Heater

PTC heaters energy saving anyway

A heating components are used in similar application of PTC heater is a nichrome wire heater. Compared with Nichrome wire heater, PTC heaters do not require temperature control unit (described later) and do not consume morer electric power when the desired temperature reached which leads to energy saving. Also, PTC heaters are more durable than Nichrome wire heaters, then PTC heaters　can be used for a long time. Therefore, PTC heaters are recommened to use for heating products with low energy consumption.

It can be Temperature control easily

PTC heaters utilizing thr charaterirtics of PTC Thermistors do not require complex temparature control unit to maintain the temperature. As the resistance value increase along with temperature rise, the electric power would be cut off automatically above the certain temperature,namely, it is possible to keep the temperature. This control is according to the characteristics of PTC Thermistor and it is not neccessary for control unit with power on/off, then, switching noise do not occur. PTC heater can meet the request from the customers in case the required heater is simply put the components in or they do not want to affect oher parts of the products.

It can be heated safely

PTC heaters utilizing the characteristics of PTC Thermistor do not allow electric power to pass above the certain temperature. The temperature will not be higker than expected as the target temperature is reached and further energy is not supplied anymore. The feature of PTC heaters is safety as the heaters are not overheated without complex temperature contrrol. There is no need to use fuses to take measures against abnormal current. PTC heaters can be also used to improve products safety.

PTC Heaters are to be small in size and to have wide range in setting Temperature

PTC heaters produced by Maximum Technology Co., Ltd. have features are to be small i size and to have wide range in setting Temperature. Those PTC Heaters can be applied to many products according to their small size. And it can be fitted many applictions as the range of temperature applied is between 10℃～250℃.

We would explain on Automatically Temperature Control Function with T-R Characteristics in Fig.1
Now, PTC is operated in steady state at point "A". Under this circumstance, applied Voltage and/or ambient Temperature is to be increased, operating point is to be moved from A to B and Resistance is to be increased by Temperature increase then Current become smaller , concequently, operating point would be backfrom B to A.
The other way around, in case applied Voltage and/or ambient Temperature is to be decreased,PTC temperature is to be decreased then operation point move to C, then PTC resistance is to be smaller according to Temperature decreasing, operating point back from C to A.
According to the above,almost the constant temperature is to be kept in spite fo any change of appling voltage and ambient Temperature.

Addition to the above, Automatical Temperature Control Function of PTC would be explained by Voltage-Current Characteristics in Fig.2 PTC shows almost the constant Electric Power(W) excess the Voltage(V-I Peak).
Therefore, the Tempereture is to be almost the constant due to constant electric power against any applied voltage excess the voltage (V-I peak). In the meantime, V-I Characterisics shows the following status according to the ambient Temperature. V-I curve shows as ℓ1 at Fig.2 in case the ambient Temperarure is higher side. V-I curve shows as ℓ2 at Fig.2 in case the ambient Temperarure is lower side.
Thus, if the point A is steady state at applied Voltage E, the point will move by the Ambient Temperature change,i.e.,
incase the ambient Temperature is higher side, the point move to C(Electric power is lower)
incase the ambient Temperature is lower side, the point move to B(Electric power is higher)

Fig.5 shows Ttime-current chararisics curve for smaller resistance(B) at room temperature(RT) and bigger resistance (A) at RT. The rush current for B is bigger than the same for A but attenuation time for B is shorter then the sam for A. Less than ta , heating time for B is shorter than the same for A. But total energy at time tc is almost the same for A and B and Heating characterristics is not different from A to B.
In case the ambient Temperature is to be lower, etc. at Fig.5,the attenuation time wolud be longer and Current would be bigger.