Abstract: The invention relates to devices for the sequential testing of filters comprising couplers for connection to the filter to be tested, a first assembly having an aerosol generator and a first measuring device for determining the aerosol concentration of the air, and a second assembly having a device for sucking in air in connection with a second measuring device for determining the aerosol concentration of the air downstream of the filter. The devices are distinguished, in particular, by a short preparation time and a short postprocessing time during the measurement time of the filter to be tested. For this purpose, the raw gas-side coupler is connected to a non-return valve. Furthermore, the first assembly is connected to the raw gas-side coupler via a first shut-off valve, the second assembly is connected to the clean gas-side coupler via a second shut-off valve and the actuating devices of the shut-off valves are connected to a control device.

Abstract: The invention relates to a method and a device for operating a diesel motor using a fuel that comprises vegetable oils or recycled vegetable oils. The fuel is withdrawn from a tank, filtered through a fuel filter and injected into the cylinders through injection nozzles by means of an injection pump. Any excess fuel is returned. The fuel is transferred from the tank via pressure-resistant fiber filters by means of a forcing pump to a storage reservoir, where it is irradiated ultrasonically. The fuel is sucked out of the storage reservoir by the injection pump and excess fuel is returned to the storage reservoir.

Abstract: The resistor is designed in the form of a column and has a cylindrical resistor body which is arranged between two planar electrodes, aligned parallel, and is made of a ceramic material. The resistor is preferably a varistor on a metal-oxide base, and is then used as a voltage-limiting element in an overvoltage suppressor. The strength of the ceramic material and the length of the resistor are chosen to be as great as possible. However, the length of the resistor is at most sufficiently large that damage to the ceramic resistor body caused by thermally produced pressure waves is avoided when the resistor is loaded in an electrical field of given magnitude with at least one highly energetic current pulse of defined amplitude, form and duration.

Abstract: An electrical arrester structure includes an arc quenching chamber in which are located a pair of spaced principal electrodes between which a quenched arc gap is formed, an associated blow-out coil for magnetically influencing and expanding the arc formed between these electrodes and an auxiliary electrode which together with the principal electrode adjacent thereto forms an auxiliary arc gap. The auxiliary electrode is connected directly to one end of a leakage resistor and the other end of this leakage resistor is electrically connected either through the blow-out coil or directly to the principal electrode which is adjacent the auxiliary electrode with the result that the auxiliary arc gap will fire before the voltage protective level of the arrester is reached and cause the leakage resistor which is series connected with the quenched arc gap to be bridged.

Abstract: An electrical arrester includes one or more pairs of electrodes disposed within quenching chambers which form current-limiting quenched spark gaps connected in series with an associated blow-out coil for magnetically influencing the arc in the quenching chambers. During the quenching operation, the blow-out coil is short-circuited and two different embodiments are disclosed for effecting this result. In one embodiment, the quenching chamber includes a short-circuiting electrode in the vicinity of that one of the electrodes of a pair which is conductively connected to one end of the blow-out coil and the other end of the latter is conductively connected to the short-circuiting electrode. In the other embodiment, the arrester includes a pair of auxiliary electrodes disposed within an auxiliary chamber and forming a by-pass spark gap connected in parallel with the blow-out coil.