DYTRAN Instruments’ 4151HL is an advanced vibration/acoustic meter, available from Kingdom . It utilises an IC true rms to dc converter to transform the input from standardised Dytran LIVM (voltage mode, constant current, ICP) accelerometers to a dc voltage displayed on a large analogue front panel meter calibrated directly in Gs rms.
A four position rotary switch and a choice of two sensor sensitivities (10 or 100 mV/g) provide six ranges from 1G to 500G full scale.
A self contained dc current source supplies power to a voltage mode constant current (ICP) accelerometer. The Model 4151HL has a variable high limit point which can be set from the front panel. A red LED indicates when a high limit has been exceeded.
The rear panel terminal block has a normally open or normally closed option to make or break a circuit. This allows the 4151HL to shut down a machine if vibration limits are reached due for example to a failed bearing. Machines can also be started up and/or alarms sounded if the limit is reached due to earth shake.
The 4151HL displays the true rms value of a vibration wave form irrespective of wave shape. It has a wide frequency range with four switch selected ranges.
The meter provides a 0-10V dc output signal for each range. The 0-10V dc output is available at a BNC jack on the rear panel for use in a control loop. A monitor jack at the front panel allows monitoring of the actual accelerometer wave form with an oscilloscope. A push button on the front panel checks the condition of accelerometer and cables.
The unit may also be used as a four range true rms voltmeter (0.1, 0.5, 1.0 and 5.0V rms). This meter can be easily rack mounted with a single thumbscrew.
The 4151HL is suitable for laboratory, research and development, and OEM applications.