Instantel 716A0401, Руководство оператора

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Compliance Module
MiniMate Plus Operator Manual
3–9
channel histogram events can be printed by the monitor using an optional printer, eight channel
events cannot. To print eight channel events, use the BlastWare III software program.
In this mode, the MiniMate Plus stores summary event information in intervals rather than in the
real time continuous method used in the other record modes. The monitor samples data
continuously at the chosen sample rate but only stores the relevant peaks for the interval. This
reduces the data recorded to specific criteria only and greatly increases the monitor’s recording
time. For each interval, the monitor calculates the maximum positive and negative peaks, the
frequency of the largest peak, and up to two peak vector sums (one with four channel monitors,
two with eight channel monitors). For each channel, the maximum peak, its frequency, and the
largest peak vector sum is calculated over the entire event.
Note: Histogram record mode consumes more battery power than the Single Shot, Continuous or
Manual recording modes. We recommend connecting a monitor to the AC adapter or an
external 12 VDC power supply.
e. Histogram Combo Record Mode
This mode creates a waveform during histogram recording if the signal exceeds the waveform
trigger level. The waveform event is saved as a separate file while the histogram event file
remains continuous. Up to 13 waveform events can be stored. The auxiliary trigger is disabled
during histogram combo mode.
The maximum sample rates in this mode are as follows:
a. 4 channels or less: 2048 samples per second
b. more than 4 channels: 1024 samples per second
Note: Histogram Combo record mode consumes more battery power than the Single Shot,
Continuous or Manual recording modes. We recommend connecting a monitor to the AC
adapter or an external 12 VDC power supply.
To Select a Record Mode:
Press the Setups key. Press the Enter key to display the Recording Mode: Window. Press the Up
or Right Arrow key to scroll through the record modes. Press the Enter key to select a record
mode when it appears on the display.
3.8.2. Sample Rate
The MiniMate Plus offers three sample rates: a standard rate of 1024 samples per second, a fast
rate of 2048 samples per second, and a faster rate of 4096 samples per second (on channels 1 to 4
only). Increasing the sample rate increases the accuracy of the waveform recording. For this
reason, set the sampling rate according to the location of the MiniMate Plus or the standard
transducer. For close–in monitoring, set the sample rate to 4096 samples per second. For far–field
monitoring, set the sample rate to 1024 samples per second.
Aliasing occurs when a high–frequency signal appears as an erroneous low frequency because the
waveform was sampled at too low a sampling rate. An anti-aliasing filter solves this problem by
removing the high–frequencies before they can appear at lower frequencies. The MiniMate Plus
standard sensors have anti-alias sensors built into them to avoid this problem.
To choose a sample rate, press the Setups key with the Main Window displayed. Use the Enter
key to scroll through the windows until the Sample Rate Window appears. Press the Right Arrow
key to scroll through the available sample rates. Press the Enter key to select a sample rate when
it appears on the display.