Over-temperature Protection

Figure 3.14 Thermal curves to set the relay for over-temperature protection corresponding to different overload conditions...

Of course the only way to keep this 250W behemoth running for more than a minute without hitting the IC s internal OTP (over temperature protection) was to use a water-cooled heatsink, which my rather lab-ratty senior tech fashioned in less than half a day with some tubes, strips of metal, high-temp solder, and a sump (submersible pump). Note that the dissipation in the TO-220 was about 15W at this power level (calculated and measured). Yes, if you think that is a wee bit too much for a TO-220 to handle, I am on your side. 

Under-Frequency and Over-Temperature Protection of Gas-T irbine Driven Generators... 

Temperature Control Control (tf extractor and inlet temperature with over temperature protection. Monitors for extractor, separator and SCF inlet temperature. 

Conductive polymer composites (CPC) exhibit a series of unique features, such as comparatively low room temperature resistivity, percolation phenomenon, resistivity sensitivity to temperature, pressure and gas, and nonlinear voltage-current relationship [1-5]. They found wide industrial applications in the fields of antistatic materials, self-regulating heaters, over-temperature protection devices, and electromagnetic interference shielding. Therefore, fundamental and applied studies of CPC are currently of great interest. 

Some examples of such potential common-cause failures or other events would include rapid release of energy from concentrated sources such as uncontained failures of rotating parts or pressure vessels, pressure differentials, non-catastrophic structural failures, loss of environmental conditioning, disconnection of more than one subsystem or component by over-temperature protection devices, contamination by fluids, damage from localised fires, loss of power, excessive voltage, physical or environmental interactions among parts, human or machine errors, or events external to the system or to the aeroplane. 

Dommer. R. and Rotter, N W., Temperature sensors for thermal over-load protection of machines, Siemens Circuit, XVII, No. 4, October (1982). 

A fire suppression system should be provided around the dispenser to protect personnel and vehicles from fire during refueling. Actuation shall be provided both by sensors automatically and through the use of a manual switch. LP gas tanks that can be exposed to fire should have water spray fixed systems to prevent the tanks from failure due to over-temperature. The direct application of water in the form of a spray can also be used to control unignited gas leakage. 

Each chlorine ton cylinder has three fusible plugs on each end of the tank to protect it from over-temperature. These plugs are designed to melt between 158° and 165° F (70° to 74° C). They are designed to protect the tank from overpressure if the cylinder is accidentally... 

The protection philosophy seems to be to protect the cylinder from overpressure by protecting it from over-temperature that would vaporize the liquid chlorine. Each of the fusible plugs is in a 3/4-inch threaded plug. If the fuse melts, the resulting hole is about 11/32 inch in diameter. 

The upper plenum thermal protection structure is composed of two basic elements 1) a "hot" shroud into which, during normal and SCS operation, gas is exhausted from channels attached to the core barrel and from the core during pressurized conduction cooldown, and 2) a thermal barrier, consisting of insulation and coverplates, that is attached to the outside of the shroud and is designed to protect the reactor vessel from over temperature during the pressurized conduction cooldown. Figure 4.4-14 shows the basic form of the structure. 

This system provides for overpressure protection of the RCS at reduced temperatures and pressures and therefore addresses the LTOP issue. The over-pressure protection for the RCS is accomplished by providing a relief path through special LTOP relief valves incorporated in the SCS for the RCS during heatup and cooldown. The LTOP relief valves are sized and adjusted to the appropriate setpoint(s) to ensure adequate overpressure protection for the RCS at reduced temperatures and pressures see CESSAR-DC, Section 5.2.2.10. 

Protective functions Overload H2 inlet pressiue high or low system output voltage high or low short circuiting stack over-temperature environment temperature high or low... 

Protection Over current, over voltage, short circuit, over temperature, and under voltage. No damage caused by output short circuit. The inverter must shut down if the input voltage dips below the minimum input of 42 V. Inverter should not self-reset after a load-side fault. IEEE Standard 929 is a useful reference. 

The stability of the working standard solution and sample solution should be assessed over a minimum of 24 h, ideally up to at least 7 days, at several conditions, for example, room temperature, room temperature protected from light, and refrigerated. The stability may be assessed versus freshly prepared standard solutions and/or by monitoring total impurities. 

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