1. The influence of the installation position of the thermal protector on the selection of the operation temperature

The installation position of the product should be fully considered when selecting the operation temperature

A. When installed on the MOS tube, the temperature protection temperature of the temperature control switch is generally lower than 125 degrees, mainly to protect the MOS tube from burning down due to overthermaling;

B. When it is installed on the coil of the transformer, the insulation level of the enameled wire should be considered. The protection temperature of the temperature control switch should be lower than the thermal-resistant temperature of the insulation level of the enameled wire;

C. When the switch is installed on the housing or thermal sink, the protection temperature of the temperature control switch is generally low because thermal is lost when transmitted from the thermaling source to the housing or thermal sink.

2. Rated voltage and current of the circuit
For example, the switching power supply scheme will generally put the temperature control switch in the control loop, so the voltage and current are very small, mainly used to transmit signals, the influence on the temperature switch is not big. Normal HKW9700 series (24V 6A) can meet.

3. Size of installation space
The application design of an electronic product usually meets the product function design first, and the power supply is considered last. However, when entering the stage of power switch design, it is often found that the space available for the equipment is very little. The common method is to find a small volume switch power adapter, so the compact power switch also has higher requirements for the volume of the thermal protector.

HKW9700D series is a very high cost performance and small volume strip temperature switch, size of 15x7x3.5mm, can meet 95% of the power supply due to compact product structure and requirements of small volume temperature switch. For ultra-thin power supply with more demanding volume requirements, we generally recommend HKW9700B series with better performance and only 12x5.4x2.4mm in volume.