Abstract: A conveying installation by way of which the 3D printing rate can be increased and the reliability of transporting a semi-finished product to be processed in an additive manufacturing machine can be improved.

Abstract: Voltage sensor (1) comprising a voltage divider (40) for sensing an AC voltage of a HV/MV power conductor (10). For adjusting the common overall impedance of the low-voltage portion of the voltage divider towards a desired impedance, the low-voltage portion (60) comprises one or more low-voltage impedance elements (110), a plurality of adjustment impedance elements (80) and a plurality of switches. In its connect state, each switch electrically connects an adjustment impedance element in parallel to at least one of the one or more low-voltage impedance elements (110). The overall impedance of the high-voltage portion (50) and the overall impedance of the low-voltage portion (60) of the voltage divider (40) are adapted such that, by bringing one or more of the switches (90) into their connect state, the voltage divider (40) has, for an AC voltage of between 5 and 25 kV phase-to-ground and a frequency of between 40 and 70 Hertz, a dividing ratio of 3077, of 6154, of 6769 or of 10 000.

Abstract: A method tests the strings of a photovoltaic system, and a photovoltaic inverter has for each string a relay, a current-measuring device and a voltage measuring device, connected to a control device. The control device is designed to control each relay, each current-measuring device and the voltage-measuring device in such a way as to automatically ascertain at least individual values of the U/I characteristic curve of each string. The control device is connected to at least one interface for connection to sensors for measuring environmental parameters in the region of the string and is connected to a memory for storing the ascertained values for creating a test report. The control device is further designed to convert the ascertained values optionally to Standard Test Conditions under defined environmental conditions and to compare the ascertained values with values which are stored in the memory.

Abstract: The invention relates to a method for testing the strings (3) of a photovoltaic system, and also to a photovoltaic inverter (1) for carrying out this method.

Abstract: A method and a device for combining an auxiliary stack and a main stack include a rake carrying the auxiliary stack and being abruptly movable out of a stack area to prevent sheets that contact the rake from being entrained and to preserve the structure of the stack. A sheet-fed printing press or sheet punching machine having the device is also provided.

Abstract: A device for combining an auxiliary stack with a main stack includes an auxiliary stack carrier which holds the auxiliary stack and which can be moved out of the stack area for combining the stacks. A holding device firmly holds a lower sheet of the auxiliary stack and an upper sheet of the main stack as the auxiliary stack carrier is moved out of the stack area, in order to maintain a good stack structure. A sheet-fed printing press or sheet punching machine having the device is also provided.

Abstract: A method and a device for combining an auxiliary stack and a main stack include a rake carrying the auxiliary stack and being abruptly movable out of a stack area to prevent sheets that contact the rake from being entrained and to preserve the structure of the stack. A sheet-fed printing press or sheet punching machine having the device is also provided.

Abstract: A device for combining an auxiliary stack with a main stack includes an auxiliary stack carrier which holds the auxiliary stack and which can be moved out of the stack area for combining the stacks. A holding device firmly holds a lower sheet of the auxiliary stack and an upper sheet of the main stack as the auxiliary stack carrier is moved out of the stack area, in order to maintain a good stack structure. A sheet-fed printing press or sheet punching machine having the device is also provided.

Abstract: A method and apparatus for supplying a liquid medium, such as viscous printing ink, to the distributor and transfer rollers of printing machines. The apparatus includes an arcuate shaped distributor plate, an ink feed for dispensing a controlled quantity of liquid medium onto the distributor plate, and a feed roller that is mounted for cyclic movement in a path whereby it is rolled on the distributor plate to mix and uniformly spread the medium along the plate and about the periphery of the feed roller and then is moved into contact with the machine distributor roller to transfer the liquid medium thereto in a controlled manner. In one embodiment, the feed roller is moved in a cyclic circular path so that it first engages the distributor plate and then the distributor roller, and in another embodiment is moved in a reciprocating manner back and forth on the distributor plate and then engages the distributor roller.

Abstract: A closed-cycle multi-step thermochemical process is described for the production of hydrogen and oxygen from water. The disclosed process utilizes auxiliary compounds of the system iron-chlorine. By using the following two basic process steps:A. reacting an iron oxide with hydrogen chloride or a mixture of hydrogen chloride and chlorine to form iron (II) chloride or iron (III) chloride andB. reacting iron or iron (II) oxide with water to form iron (II) oxide or iron (II) (III) oxideIt is possible to employ a variety of additional steps so that the sum total of the reaction steps consume water, produce hydrogen and oxygen and regenerate the desired starting materials within the closed system.