Bently Nevada 3500/40M Datasheet

3500/40M Proximitor Monitor

Datasheet

Bently Nevada Machinery Condition Monitoring

Description

The 3500/40M Proximitor Monitor is a four-channel monitor
that accepts input from Bently Nevada proximity transducers,
conditions the signal to provide various vibration and
position measurements, and compares the conditioned
signals with user-programmable alarms. The user can
program each channel of the 3500/40M with the 3500 Rack
Configuration Software to perform any of the following
functions:

l Radial

vibration

l Thrust

position

The primary purpose of the 3500/40M Proximitor Monitor is to
provide the following:

l Eccentricity l REBAM

l Differential

expansion

141535 Rev. L



l Machinery protection by continuously comparing

monitored parameters against configured alarm
setpoints to drive alarms

l Essential machine information for both operations and

maintenance personnel

Each channel, depending on configuration, typically
conditions its input signal to generate various parameters
called static values. You can configure alert setpoints for
each active static value and danger setpoints for any two of
the active static values.

You program the monitor channels in pairs. The
monitor channels can perform up to 2 of these
functions at a time. Channels 1 and 2 can perform one
function, while channels 3 and 4 perform another (or
the same) function.

3500/40M Proximitor Monitor
Datasheet 141535 Rev. L

Proximitor is in Bypass Mode.

Specifications

Inputs

Signal

Power
consumption

Standard I/O

TMR I/O The effective impedance of

Sensitivity

Radial
Vibration

Thrust 3.94 mV/μm (100 mV/mil) or

Eccentricity 3.94 mV/μm (100 mV/mil) or

Differential
Expansion

REBAM

Outputs

Front Panel LEDs

Accepts from 1 to 4 proximity
transducer signals

7.7 watts, typical

Input Impedance

10 kΩ
(Proximitor and acceleration
inputs

three bussed TMRI/O
channels wired in parallel to
one transducer is50 kΩ

3.94 mV/μm (100 mV/mil) or

7.87 mV/μm (200 mV/mil)

7.87 mV/μm (200 mV/mil)

7.87 mV/μm (200 mV/mil)

0.394 mV/μm (10 mV/mil) or

0.787 mV/μm (20 mV/mil)
40 mV/μm (1000 mV/mil) or

80 mV/μm (2000 mV/mil)

Buffered
Transducer
Outputs

Output
Impedance

Transducer
Power
Supply

The front of each monitor has
one coaxial connector for each
channel.

Each connector is short-circuit
protected.

550 Ω

-24 Vdc

Signal Conditioning

Specified at +25 ºC (+77 ºF) unless
otherwise noted.

Radial Vibration

Frequency Response

Direct filter

Gap filter -3 dB at 0.09 Hz

Not 1X filter 60 cpm to 15.8 times running

Smax 0.125 to 15.8 times running

1X and 2X
vector filter

User-programmable
Single-pole
4 Hz to 4000 Hz or
1 Hz to 600 Hz

speed
Constant Q notch filter
Minimum rejection in
stopband of -34.9 dB

speed
Constant Q Filter

Minimum rejection in
stopband of -57.7 dB

OK LED Indicates when the 3500/40M SIL

Proximitor is operating properly.

TX/RX LED

Bypass LED Indicates when the 3500/40M SIL

Indicates when the 3500/40M SIL
Proximitor is communicating
with other modules in the 3500
rack.

1X and 2X Vector, Not 1X, and Smax
parameters are valid for machine
speeds of 60 cpm to 60,000 cpm.

2/12

3500/40M Proximitor Monitor
Datasheet 141535 Rev. L

Accuracy

Direct and Gap

1X and 2X Within ±0.33% of full-scale

Smax Within ±5% maximum

Not 1X

Exclusive of filtering
Within ±0.33% of full-scale
typical
±1% maximum

typical
±1% maximum

±3% for machine speeds less
than 30,000 cpm
±8.5% for machine speeds
greater than 30,000 cpm

Thrust and Differential Expansion

Accuracy Within ±0.33% of full-scale

typical
±1% maximum

Frequency Response

Direct filter

Gap filter -3 dB at 0.41 Hz

-3 dB at 1.2 Hz

Frequency Response

ranging from 0.139 to 3836 Hz

High-pass corner is 0.8x
BPFO.
Low-pass corner is 2.2x BPFO.

Rotor

User programmable from

0.108 to 2221 Hz

Direct Programmable from 3.906 to

14.2 Hz

Selection is determined by
Spike and Rotor filters.

Gap

Programmable from 0.002 to

1.0 Hz

Selection is determined by
the Rotor filter.

1X vector filter The range of shaft speeds for

which the value is valid
depends on the nominal
shaft speed for which the
channel is configured.



Table 1: Relationship Between Nominal Shaft
Speed and the Valid Speed Range

Eccentricity

Accuracy Within ±0.33% of full-scale

typical
±1% maximum

Frequency Response

Direct filter

-3 dB at 15.6 Hz

Gap filter -3 dB at 0.41 Hz

REBAM

Frequency Response

Spike User-programmable

from 0.152 to 8678 Hz

Element

User-programmable for
BPFO

Nominal Shaft

Speed (Hz)

10 to <126

Valid Speed Range (Hz)

0.071 to 160

126 to <252 0.133 to 330

252 to <504 0.25 to 660

504 to 584 0.50 to 750

If a multi-event gear or speed wheel
generates the speed input, the upper
limitation of the resultant input signal is
approximately 20 KHz.

Filter Quality

Spike high­pass

6-pole Elliptic
(155 dB per decade,
minimum)

3/12

3500/40M Proximitor Monitor
Datasheet 141535 Rev. L

Element
bandpass

Rotor low-pass

Rotor, direct
high-pass

Spike, direct
low-pass

Gap low-pass

Filter Quality

Corner frequency is -0.1 dB.

8-pole Butterworth
(155 dB per decade
minimum)

Corner frequency is -3 dB.

6-pole Elliptic
(155 dB per decade,
minimum)

Corner frequency is -0.1 dB.

1-pole Butterworth
(18 dB per decade,
minimum)

Corner frequency is -3 dB.

Corner is -0.3 dB maximum.

1-pole Butterworth
(18 dB per decade,
minimum)

Corner frequency is -3 dB.

 Accuracy

channel of a channel pair.



Filter Tracking / Stepping (Requires a valid

speed signal)

Initial condition Nominal filter set used

Switch from
nominal to

Current shaft speed ≤ 0.9 x
(nominal shaft speed)

lower filter set

Switch from
lower to

Current shaft speed ≥ 0.95 x

(nominal shaft speed)
nominal filter
set

Switch from
nominal to

Current shaft speed ≥ 1.1 x

(nominal shaft speed)
higher filter set

Switch from
higher to

Current shaft speed ≤ 1.05 x

(Nominal Shaft Speed)
nominal filter
set

1X amplitude

Constant Q of 16.67

Stopband frequencies are

0.91 and 1.09 times the
running speed.

Stopband attenuation is -51
dB minimum.



 Accuracy

Amplitude

Within ±0.33% of full scale
typical

±1% maximum when input
signal is at the center
frequency of the measured
value's passband

Phase 3 degrees error, maximum

Channels
enabled

Certain configurations allow
the user to enable only one

Shaft speed
error condition

Nominal filter set used

4/12