Overview of the 500 Series Thermal Switch
Designed for both commercial and military environments, these hermetically sealed, single pole, single throw (SPST) switches are ideal for critical temperature control, indication, and limiting functions.
Manufactured in a controlled environment, each switch undergoes rigorous computerized setpoint testing to ensure accuracy and uniformity.
Nine standard mounting configurations are available. They are easily adaptable for special designs in industrial, aeronautic, and military applications, and are qualified to MIL-PRF-24236/1. The 500 Series is qualified to MIL-PRF-24236/1.
Thermal switches exported from the United States must be done in accordance with the export administration regulations (EAR) and/or the international traffic in arms regulations (ITAR) as applicable.
Key features
- All welded hermetic construction
- Operating temperatures available from -65°F to +350°F
- High vibration resistance
- High and low current capability
- Crisp SPST contact operation
- Fast response to thermal changes
- Lightweight and rugged
- Backfilled with dry Nitrogen gas containing 10% Helium tracer
- Tested to 63.5g rms random vibration levels
- Special materials and finishes can be provided
- Custom units available to over +600°F
- Non-standard tolerances available upon request
- Additional configurations available*
Custom features
- Special terminal configurations, plating, overmolds and lead
wires are available* - Unusual temperature ranges and setpoint tolerances
available* - Special identification requirements
- Custom shapes, assemblies, materials and finishes can be provided
*Inquire for more information.
Typical applications
- Electronics compartment temperature control
- Industrial bath temperature control
- Gyro/accelerometer system temperature control
- Duct air temperature control
- Motor overheat protection
- Hydraulic pump/system overheat protection
- Bearing overheat warning
- Gearbox overheat warning
- Battery charge rate and overtemp control
- Heatsink overtemp warning
- Surface and strip heater control
Technical specifications
Performance characteristics
| Contact arrangement | SPST |
| Contact ratings |
|
| Contact resistance | 20 milliohms maximum |
| Endurance | 100,000 cycles minimum at rated DC or AC load |
| Dielectric withstand | 1500 VAC RMS - terminals to case, 500 microamperes maximum leakage |
| Insulation resistance | 500 megohms minimum at 500 VDC |
NOTE: The 500 Series Thermal sSwitches have been qualified to the requirements of Military Specification MIL-PRF-24236, titled “Switches, Thermostatic, General Specification For”.
Environmental information (MIL-STD-202)
| Vibration (sine) | Method 204, 50g to 2000 Hz, 30g to 2000 Hz |
| Vibration (random) | Method 204, over 60g RMS, 20 to 2000 Hz |
| Shock | Method 213, 100g/6ms, 750g/0.5ms |
| Thermal shock | Method 107, Condition B, -85° to +257°F (-65°C to 125°C) |
| Acceleration | Method 212, Condition A, 30g |
| Salt spray | Method 101, Condition B, 48 hours |
| Moisture resistance | Method 106, 240 hours, 90 - 98% RH and from +77°F to +149°F (+25°C to 65°C) |
| Hermetic seal |
Method 112, Condition C, Procedure IV |
Temperature setpoint ranges and tolerances
| Specified temp setpoint range °F (°C) | Standard setpoint tolerance °F (°C) |
| –65 to 0 (–54 to –18) | ±6 (±3.3) |
| +1 to 250 (–17 to 121) | ±5 (±2.8) |
| 251 to 350 (122 to 177) | ±7 (±3.9) |
More Thermal Switches
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