| 摘要 |
The invention relates to a pulse transmitter, whose number of pulses can be predetermined, for testing measurement and monitoring equipment which transmit pulses, especially measurement and monitoring equipment having a NAMUR (German Metrology and Control Technology Standards Committee) amplifier, having an oscillating crystal as a pulse generator whose high oscillation frequency is divided down, by means of a frequency divider, to a frequency of a few Hertz. The output pulses from the frequency divider are passed to a switching element, which is preferably a flipflop in a master-slave circuit, the output of the switching element being applied simultaneously to a pulse counter, which can be preset, and to the excitation coil of a relay. On reaching the predetermined number of pulses, the pulse counter switches the pulse generator off. The switching contact of the relay acts with the number of pulses in a floating manner on an output contact to which (and at the same time to the switching contact of the relay) the voltage inputs and outputs of the equipment to be tested are connected. The voltage of this equipment is now chopped in time with the pulses from the relay. <IMAGE>
|
