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Entek IRD 6652 DSP Protection Monitor
Configuration
Nominal transducer sensitivities
The values in the following table are the nominal sensitivities for some common transducers
used with the 6652 DSP. If the measured sensitivity for a transducer is available from the
manufacturer or installation, use that value for TX SNS instead of the nominal value.
Setting MX SIG
The MX SIG option sets the input range to the digital signal processor chip in the monitor. If
MX SIG is set too high, the input range may be too high for the signal (insufficient
resolution). If set too low, the input signal may be clipped. This is particularly important for
integrated measurements (acceleration to velocity or velocity to displacement).
For non-integrated measurements, setting MX SIG to 7000 should provide sufficient range
and resolution. For integrated and low-amplitude measurements, you can use the following
example (modified for your configuration) to find a value for MX SIG.
Transducer: 100 mV/g
Display full scale: 10 mm/s rms
High/low pass filters: 10 Hz and 85 Hz (cycles/second)
acceleration (g pk)
= maximum frequency x velocity (mm/sec rms)
= 85 Hz x 10 mm/sec = 1103 mm/sec
2
rms
= 1.5 g pk-pk (convert mm to g, rms to pk-pk)
Then multiply by an additional factor of 5 to get the value for MX SIG:
1.5 g pk-pk x 5 = 7.5 for MX SIG
SCALE 1 and SCALE 2 submenus
The SCALE 1 and SCALE 2 submenus have the following options. The options are the
same in the two menus. SCALE 1 contains the channel 1 options. SCALE 2 contains the
channel 2 options.
Transducer
Nominal sensitivity
403 and 1900 non-contact probes (peak to peak)
200 mV/mil
7.86 mV/µm
Factory menu
→
RANGES
→
RANGE 1
→
SCALE 1
FS LO 1
0.00
INS/S
EXIT
SET
FS HI 1
10.00
INS/S
FS HI 1
Choose the full scale value for the monitor for channel 1 (0.00–9999.99).
This also sets the display full scale and the 20 mA point for the 4–20 mA
outputs.
FS LO 1
Not used with the 6652 DSP (6682 DSP monitor feature).
EXIT
Return to the RANGE1 submenu. The monitor remembers the current
values for menu options, but does not write them to memory until you exit
the Factory menu.
