Detector switches used in harsh environments need to be highly reliable*. If a high degree of safety is also a requirement, resistors can be incorporated into the switch to make it possible to detect faults, distinguishing between a switch off state and a circuit break, and between a switch on state and a short circuit.
*Find out more about detector switch reliability here.
Structure and Features of Internal Resistor Type Detector Switches
Internal resistor type detector switches are exactly that – switches with resistors incorporated into the circuit.
Conventional detector switches did not make any judgment as to whether a switch had turned off or a circuit break had occurred. (Short circuits were not identified either.) Wiring resistors into the switch circuit makes it possible to distinguish between a switch off state and a circuit break (or between a switch on state and a short circuit) by having different output voltages.
| Switch off | Switch on | Circuit break | Short circuit | Output waveform | |
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Resistors have previously been used outside the switch circuit as a way to detect circuit breaks and shorts, but this method does not allow identification of breaks and shorts occurring between the switch and the resistors. It also requires a larger mounting area. By incorporating the resistors into the detector switches as internal resistors, both mounting area and the number of parts can be reduced.
Internal Resistor Type Detector Switch Lineup
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| Dimensions | 8.3×5.3×7.3mm (industry-smallest class) | 13.3×5.3×7.0mm | |
| Chip resistor specs | Chip resistor dimensions | 1608(1.6W×0.8Lmm) | |
| Chip resistor tolerance (%) | ±1% (standard) | ||
| Chip resistor rated power | Max. 0.33W | ||
| Circuit diagram |  |
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| No. of chip resistors | 2 pcs | ||
| Terminal type | For PC | - | |
| Press-fit (normal) | Press-fit (normal) | ||
| Press-fit (short) | - | ||
Part numbers are determined by the resistance values of R1 and R2.
Specifications such as resistor resistance values and control part design will be individually accommodated. Please contact an Alps Alpine sales representative.
View contact information here.
Internal Resistor Type Detector Switch Application Examples
Automobiles are not the only domain where detector switches are used in harsh environments.
Dishwashers
Washing machines
Vacuum cleaners
Power tools
Some applications demand higher levels of safety.
Electric scooters
Smart meters
Smart locks
Equipment and machinery
More Information
Alps Alpine has an extensive lineup of detector switch varieties in addition to internal resistor types.
