3500/25 Enhanced Keyphasor Module
Datasheet

Bently Nevada Machinery Condition Monitoring141532 Rev. VDescription
The 3500/25 Enhanced Keyphasor Module is a half-height,
two-channel module used to provide Keyphasor signals tothe monitor modules in a 3500 rack. The module receives
input signals from proximity probes or magnetic pickups andconverts the signals to digital Keyphasor signals that indicate
when the Keyphasor mark on the shaft coincides with theKeyphasor transducer. The 3500 Machinery Protection
System can accept up to four Keyphasor signals for normal
configuration and up to eight Keyphasor signals in a paired
configuration.
Keyphasor signal is a once-per-turn or multipleevent-per-turn pulse from a rotating shaft or gear
used to provide a precise timing measurement. This
allows 3500 monitor modules and external
diagnostic equipment to measure shaft rotative
speed and vector parameters such as 1X vibration
amplitude and phase.
The Enhanced Keyphasor Module is an improved 3500
system module. It offers expanded Keyphasor signal
processing capabilities over the previous design while
maintaining complete downward-compatibility in terms ofform, fit and function with existing Keyphasor modules for usein legacy systems. The Keyphasor module, PWA 125792-01, iscompletely replaced by the updated 149369-01 module.
When a system Keyphasor input is required for Triple Modular
Redundant (TMR) applications, the 3500 system should
employ two Keyphasor modules. In this configuration, themodules work in parallel to provide both a primary andsecondary Keyphasor signal to the other modules in the rack.

3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. VA system with more than four Keyphasor inputs
may use a paired configuration provided there
are no more than four primary Keyphasor input
signals. A paired configuration requires twoconsecutive monitoring positions in either theupper/lower or both half-slot positions. Four
Keyphasor modules will accept four primaryand four backup input channels and provide
four output channels (one per module). A
configuration of two paired and one nonpaired (three Keyphasor modules total) is also
possible. In such a configuration, the user may
configure the one non-paired Keyphasor (ordereither two 2-channel or one 1-channel and one2-channel option)
The Isolated Keyphasor I/O module is designed
for applications where the Keyphasor signals
are tied in parallel to multiple devices andrequire isolation from other systems, such as acontrol system. The Isolated I/O module wascreated specifically for Magnetic Pickup
applications but is compatible with and will
provide isolation for Proximitor* applications aslong as an external power supply is provided.
The intent of this I/O module was primarily tomeasure shaft speed and not phase. Themodule can provide phase measurements, but
this I/O introduces a slightly higher phase shift
than the Non-Isolated I/O version. Figure 1
shows the amount of phase shift that theIsolated I/O modules will add at different
machine speeds.
Enhanced product features include generationof once-per-turn event signals from multievent-per-turn inputs, field-upgradeable
firmware, and asset management datareporting.

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3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

Transducer Conditioning

Specifications
InputsPowerConsumption

3.2 Watts typicalSignalEach Keyphasor Module
accepts up to twotransducer signals fromproximity probe transducers
or magnetic pickups. The
input signal range is +0.8 V
to -21.0 V (NonIsolated I/Omodules) or +5V to -11V
(Isolated I/O modules).
Signals exceeding this range
are limited internally by themodule. Passive magnetic
pickups require a shaft
rotative speed greater than
200 rpm (3.3 Hz).

Input
Impedance

Nonprocessed
Signals

Processed
Signals

ManualThreshold

Use for any input above 0.017 Hz(1 rpm for 1 event per revolution).
User-selectable from 0 to -20
volts dc. Minimum signal
amplitude for triggering is 500
millivolts peak to peak.

Hysteresis

User-selectable from 0.2 to 2.5
Volts.

Buffered
Keyphasor
Signals

Two buffered Keyphasor
outputs are available at thefront of the rack via coaxial
connectors. Two buffered
Keyphasor outputs are alsoavailable at the back of therack via Euro Style connectors.

OutputImpedance

504 Ω maximum buffered
output impedance.

Input range of 1 to 1,200,000 cpm(0.017 to 20 kHz). Supports
multiple events per revolution toa maximum of 20 kHz.

Keyphasor
TransducerPower
Supply-24 Vdc, 40 mA maximum perchannel.

Output range of 1 to 99,999 cpm

Front Panel LEDs

21.8 kΩ minimum(0.017 to 1667 Hz)
Speed/
Frequency
SignalAccuracy

Minimum signal amplitude fortriggering is 2 volts peak to peak
and minimum frequency is 120rpm (2 Hz).

Outputs

Signal Conditioning

Speed/
Frequency
SignalRangesAutoThreshold

OK LED

Indicates when a fault has
been detected in theKeyphasor Module.

TX/RX LED

Indicates when the Keyphasor
Module is communicating with
the Rack Interface Module(RIM).

Specified at +25°C (+77°F).

0.017 to 100 Hz … ±1 cpm
101 to 500 Hz … ±8 cpm
501 to 20 kHz … ±1% of cpm
0.017 to 60 Hz … ±1 cpm
61 to 150 Hz … ±8 cpm
151 to 20 kHz … ±1% of cpm

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3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

Environmental Limits

OperatingTemperature-30°C to +65°C (-22°F to+150°F) when used withKeyphasor I/O Module otherthan the Internal Barrierversion.
0°C to +65°C (32°F to +150°F)
when used with Keyphasor
Internal Barrier I/O Module(Internal Termination).

Storage
Temperature-40°C to +85°C (-40°F to+185°F)

Humidity

95%, non-condensing

PhysicalMain Module
Dimensions
Height x
Width xDepth)

119.9 mm x 24.4 mm x 256.5mm

Weight0.34 kg (0.76 lbs.)(4.72 in x 0.96 in x 10.10 in).

I/O Module
Dimensions(Height x
Width xDepth)
Weight241.3 mm x 24.4 mm x 103.1 mm(9.50 in x 0.96 in x 4.06 in)
0.46 kg (1.01 lbs.).

Rack Space Requirement
1 half-height front slot

Main
ModuleThe half-height main modules
require a special mounting
adapter for mounting in the fullheight slots. The user can place
the main modules in any one of
the 14 available slots. Each rack
may have no more than two
main modules, one in a top halfslot and one in a bottom halfslot.

I/O Modules 1 full-height rear slot

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3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

Hazardous Area Approvals

Compliance and Certifications

For the detailed listing of country andproduct-specific approvals, refer tothe Approvals Quick Reference Guide(108M1756).

FCC
This device complies with part 15 of theFCC Rules. Operation is subject to thefollowing two conditions:ll

For additional technicaldocumentation, please log in tobntechsupport.com and access the
Bently Nevada Media Library.

This device may not cause harmfulinterference.
This device must accept any
interference received, includinginterference that may cause
undesired operation.

cNRTLus
When used with I/Omodule ordering
options without
internal barriers

EMC
European Community Directive:
EMC Directive 2014/30/EU

T4 @ Ta= -20˚C to +65˚C (-4˚F to+149˚F)
When installed per drawing
149243 or 149244.

Standards:
EN 61000-6-2; Immunity for
Industrial Environments
EN 61000-6-4; Emissions for
Industrial Environments

When used with I/Omodule ordering
options withinternal barriersElectrical Safety
European Community Directive:

Standards:
EN 61010-1

RoHS
European Community Directive:
RoHS Directive 2011/65/EUMaritime
DNV GL rules for classification – Ships,
offshore units, and high speed and lightcraft
ABS Rules for Condition of Classification,
Part 1lClass I, Zone 2: AEx/Ex nA nC ic[ia Ga] IIC T4 Gc;
Class I, Zone 2: AEx/Ex ec nC ic [iaGa] IIC T4 Gc;
Class I, Division 2, Groups A, B, C,
and D (W/ IS Output for Division
1)
T4 @ Ta= -20˚C to +65˚C (-4˚F to+149˚F)
When installed per drawing
138547.

LV Directive 2014/35/EUl

Class I, Zone 2: AEx/Ex nA nC ic IIC
T4 Gc;Class I, Zone 2: AEx/Ex ec nC ic IIC
T4 Gc;Class I, Division 2, Groups A, B, C,and D;

Steel Vessels Rules
Offshore Units and Structures

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3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

ATEX/IECEx
When used with I/Omodule ordering
options without
internal barriers

II 3 GEx nA nC ic IIC T4 Gc;
Ex ec nC ic IIC T4 Gc;
T4 @ Ta= -20˚C to +65˚C (-4˚F to+149˚F)
When installed per drawing
149243 or 149244.

When used with I/Omodule ordering
options withinternal barriers

II 3(1) GEx nA nC ic [ia Ga] IIC T4 Gc;
Ex ec nC ic [ia Ga] IIC T4 Gc;
T4 @ Ta= -20˚C to +65˚C (-4˚F to+149˚F)
When installed per drawing
138547.

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3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

Ordering Information

Ordering Considerations

For the detailed listing of country andproduct-specific approvals, refer tothe Approvals Quick Reference Guide(108M1756).

Generallll

External Termination (ET) Blocks cannot
be used with Internal Termination I/Omodules.
When ordering I/O Modules with External
Terminations, the External Termination
Blocks and Cables must be orderedseparately.
There are many technical considerations
involved in using the expanded signal
processing functions of the Enhanced
Keyphasor Module. A qualified Bently
Nevada sales representative should beconsulted prior to specifying or ordering
modules for such applications.

For additional technicaldocumentation, please log in tobntechsupport.com and access theBently Nevada Media Library.

Enhanced Keyphasor Module
3500/25-AA-BB-CC
A: Number of channels

Internal Barrier I/O Module
Consult the 3500 Internal Barrier
specification sheet document(141495) if the Internal Barrier Option
is selected.

01

Single half-height 2-channel
Keyphasor card (order for 2-channels)

02

Two half-height 2-channel Keyphasor
cards (order for 4-Channels)

B: Type of I/O Module01

I/O module with Internal Terminations

02

I/O module with External Terminations

03

Internal Barrier I/O with Internal
Terminations

04

Isolated I/O module with Internal
Terminations (Designed for use withMagnetic Pickups)

05

Isolated I/O module with ExternalTerminations (Designed for use withMagnetic Pickups)

C: Agency Approval Option

7/1100

Not required

01

cNRTLus (Class 1, Div 2)

02

ATEX/IECEx/CSA (Class 1 Zone 2)

3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

External Termination Blocks
125800-02

Isolated Keyphasor I/O Module(Internal Terminations)(Designed for use with MagneticPickups)

126648-02

Isolated Keyphasor I/O Module(External Terminations)(Designed for use with MagneticPickups)

3500 Keyphasor (KPH) Signal to External
Termination (ET) Block Cable

135473-01

Keyphasor I/O Module (InternalBarriers and Internal
Terminations.

129530-AAAA-BB

04425545

Grounding Wrist Strap (singleuse)

A:Cable Length00580438

Connector Header, Internal
Termination, 4-Position, Green

166M2391

Connector Header, Push-inSpring Type (alternative for PN00580438)

00502133

Connector Header, Internal
Termination, 12-Position, BlueKeyphasor Module User Guide

128718-01

Keyphasor External Termination
Block (Euro Style Connectors)

128726-01

Keyphasor External Termination
Block (Terminal Strip Connectors)

Cables0005

5 feet (1.5 metres)

0007

7 feet (2.1 metres)0010

10 feet (3 metres)

0025

25 feet (7.5 metres)0050

50 feet (15 metres)

1297700100

100 feet (30.5 metres)

Half-height Blank Monitor Cover Kit

B: Assembly Instructions
01

Not assembled

02

Assembled

131151-01

Half-height Card Adapter

Spares149369-01

Enhanced Keyphasor ModuleThis module may be ordered as adirect plug-in replacement for
Keyphasor Module 125792-01.

125800-01

Keyphasor I/O Module (InternalTerminations)

126648-01

Keyphasor I/O Module (ExternalTerminations)Half-height Blank Front Panel
Cover (qty 1, includes screws)8/11

125388-01

Half-height Chassis125565-01

Card Guide

04300111

Assembly Screws (Order Qty. 3)

3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

Graphs and Figures

Figure 1: Phase Error vs. Machine Speed

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3500/25 Enhanced Keyphasor Module
Datasheet141532 Rev. V

1.
2.
3.
4.
5.
6.

Buffered Transducer Outputs
I/O Module, Isolated Internal Termination
I/O Module, Isolated External Termination
I/O Module, Non-Isolated Internal Termination
I/O Module, Non-Isolated External Termination
Barrier I/O Module, Internal Termination

Figure 2: Front and Rear View of 3500/25 Keyphasor module

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3500/25 Enhanced Keyphasor ModuleDatasheet

141532 Rev. V

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