德国Dr. E. Horn GmbH 压力表 显示器(2011-10-25 20:09:07)
希而科优势代理德国Dr. E. Horn GmbH 压力表 显示器
Horn AC tachogenerators are remote transmitters which operate regardless of the direction of rotation. The AC output voltage which is proportional to the measured speed can be used for indication, registration or for control purposes. It is possible to connect several receivers to one tachogenerator.
Standard ranges are from 0 – 25 rpm up to 0 – 10000 rpm.
Standard instruments are protected according DIN 40050 class IP54. Instruments for shipbuilding industry have a special casing of seawater resistant light alloy and a cable entry with double earthing section. Depending on the required mounting method, the generator can be supplied with spigot (z), foot (f) or flange (fl). Special executions are possible.
For dangerous areas, certain types can be supplied to comply with explosion proof requirements (Ex) e G5.
Horn DC tachogenerators produce a DC voltage proportional to the speed of the input shaft. Depending on the direction of rotation of the driving machine, the voltage will alter. Hence the generators are normally used whenever the speed in each direction has to be indicated and/or controlled, i.e. mainly in shipbuilding and in mechanical engineering.
Owing to their low output of upper harmonics, these generators are used mainly for automatic control and regulation.
The three-phase tachogenerators produce a three-phase voltage proportional to the speed, or – by means of a built-in three-phase bridge rectifier – a DC voltage, the polarity of which does not depend on the direction of rotation.
This tachogenerator has small dimensions, needs absolutely no maintenance and has very little ripple; it is therefore particularly suitable as a signal converter of actual value in closed loop speed control systems.
The rotors of models EG 66… and EG 67… are not built into the generator casing but have to be rigidly fitted to the machine shaft.
The models EG 66… and EG 67… have even smaller dimensions and can be supplied with or without a built-in rectifier.
The shaft of model EG 71.3.2 is fitted with ball bearings.