SKF Multilog IMx-S Series User manual

User manual
Copyright 2016 by SKF Group
All rights reserved.
SKF Sverige AB
Aurorum 30, 977 75 Luleå, Sweden
Telephone: [phone]
SKF Multilog On-Line
System IMx-S
User Manual Part No. 32087700-EN
Revision S –November 2019
WARNING! Read this manual before using the product. Failure to follow the
instructions and safety precautions in this manual can result in serious injury, damage to
the product, or incorrect readings. Keep this manual in a safe location for future
reference.

SKF Group
® SKF is a registered trademark of the SKF Group.
All other trademarks are the property of their respective owners.
The contents of this publication are the copyright of the publisher and may not be reproduced (even
extracts) unless prior written permission is granted. Every care has been taken to ensure the accuracy of the
information contained in this publication but no liability can be accepted for any loss or damage whether
direct, indirect or consequential arising out of the use of the information contained herein. SKF reserves the
right to alter any part of this publication without prior notice.
Patets: U“ ,, • U“ ,, • U“ ,, • U“ ,, • U“ ,, •
U“ ,, • U“ ,, • U“ ,, • U“ ,, • U“ ,, • U“ ,, •
U“ ,, • U“ ,, • U“ ,, • U“ ,, • U“ ,, • U“ ,, •
U“ ,, • U“ ,, • U“ ,, • U“ ,, • U“ ,, • U“ ,, •
U“ ,, • U“ ,, • WO//
Product Support –Contact Information
Product Support –To request a Return Authorization, Product Calibration or a Product Support Plan, use the
web page links for direct contact and support.
Product Sales - For information on purchasing condition monitoring products, services or customer support,
contact your local SKF sales office.
General Product Information
For general product information (i.e., product data sheet, accessories catalog, etc.), visit the Condition
Monitoring Products page on SKF.com and select the appropriate product link.
Technical Support Group
Discuss/review issues of specific interest with maintenance and reliability specialists from around the world
at the SKF Knowledge Centre.
For technical support, contact T[email protected] for customers in Europe, Middle East and Africa.
Telephone [phone]
or [email protected] for customers in North America, South America and Asia.
Telephone [phone]
Telephone in Latin America [phone]
Product Registration
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offered only to our registered customers, including receiving technical support, tracking your proof of
ownership, and staying informed about upgrades and special offers. (Please visit our website for more
details on these benefits.)
031616dc

SKF Multilog On-Line System IMx-S TOC - 1
User Manual –Revision S
Table of Contents
Introduction 1
Important Messages ...............................................1-1
System Overview ....................................................1-2
IMx-S Unit ...............................................................1-3
System LED Indicators ............................................1-4
Installation 2
Safety Considerations .............................................2-1
Scenario ..................................................................2-1
Supply Cable ...........................................................2-2
Mains Power ...........................................................2-2
Sensor Cables..........................................................2-4
Ethernet Cable ........................................................2-4
Ethernet Connections .............................................2-5
Cable Glands ...........................................................2-5
Unit Configuration 3
Analogue Inputs......................................................3-1
Digital Inputs...........................................................3-3
RS485 Communication ...........................................3-5
Relay Driver Outputs ..............................................3-6
Dig1 Buffered Output .............................................3-7
Network Configuration ...........................................3-8
IMx-S Time............................................................3-10
Hardware Maintenance 4
Troubleshooting Guide 5
Sensor circuits.........................................................5-1
Relay driver outputs ...............................................5-7
Connections to Monitor .........................................5-8
Checking Modbus RTU, RS485 communication......5-8
Technical Data 6
Environmental ........................................................6-1
Power Supply ..........................................................6-1
Analogue Inputs......................................................6-2
Digital Inputs...........................................................6-2
Outputs...................................................................6-2

TOC - 2 SKF Multilog On-Line System IMx-S
User Manual –Revision S
Analogue Measurement ........................................ 6-2
Digital Measurement ............................................. 6-3
Signal Processing.................................................... 6-3
Interface................................................................. 6-4
Data Processing ..................................................... 6-4
Miscellaneous ........................................................ 6-4
Quality Control....................................................... 6-4
IMx-S Drawings 7
IMx-S 16 Standard Cabinet .................................... 7-1
IMx-S 16 Stainless Steel Cabinet............................ 7-2
IMx-S 32 Standard & Stainless Steel Cabinet ......... 7-3
Terminal List .......................................................... 7-4
Electrical Waste 8
Limited Warranty A
Index

SKF Multilog On-Line System IMx-S 1 - 1
User Manual –Revision S
1
Introduction
Important Messages
The following messages are important information which require special care in order to
have a safe and reliable IMx-S system.
Important messages, instructions and information in this manual must be
carefully followed. Otherwise, harm might occur to equipment and/or personnel.
In order to install an IMx-S32-UPG-LMU (LMU/CMU upgraded to IMx-S32),
installation must be done according to the "IMx-S32-UPG-LMU Installation manual".
In order to fulfil fire enclosure requirements, ensure the following:
-The cabinet must always be mounted using all four supplied mounting brackets.
-All unused cable ways must be closed with the supplied blind plugs.
-All cable glands and blind plugs must be made of material with fire protection V-1
or better.
Important messages related to mains power (see Mains Power section as well):
-In some countries, the installer must be certified to install equipment such as an
IMx-S.
-Make sure that the power is disconnected before the installation begins.
-Mains cable must be properly fixed with a cable gland to prevent the cord from
strain, twist or movement. See Cable Glands section as well.
-To prevent a hazardous event, mains cable neutral (N) and line (L1) wires must be
secured together with a cable tie (for example, a nylon cable tie CV-100K) close to
the mains power connector.
-The system power supply must be provided with an external all pole power switch
so as to be able to disconnect the IMx-S from mains power. The switch must be
labelled "IMx-S” or siilar with the On/Off position clearly marked. The switch
must be located close to the IMx-S, within an operator's easy reach.

Introduction
System Overview
1 - 2 SKF Multilog On-Line System IMx-S
User Manual –Revision S
An IMx-S contains circuit boards that are static sensitive. Therefore, use
appropriate precautions to prevent ElectroStatic Discharge (ESD) when handling circuit
boards.
Do NOT change DIP switch settings while the IMx-S unit is powered, as this may
cause damage and void the warranty.
Before powering the IMx-S unit, make sure that DIP switch settings are properly
set to match the recommendations for the connected sensors. Incorrect settings may
cause permanent damage to the IMx-S unit.
All externally provided equipment must be evaluated individually and approved
together with the IMx-S unit regarding EMC and safety requirements (CE and ETL).
Always consult SKF before using the external mains output.
System Overview
The IMx-S is a part of the SKF Multilog On-line System product range and is designed to
be used for a variety of condition monitoring applications. In conjunction with SKF
@ptitude Observer or Analyst software, the IMx-S provides a complete system for early
fault detection and prevention, automatic advice for correcting existing or impending
conditions and advanced condition-based maintenance to improve machine reliability,
availability and performance.
Figure 1 - 1.
System Overview, IMx-S with @ptitude Observer/Analyst.
The picture above illustrates how IMx-S units are linked together in a network that is
connected via a LAN (it may also be a modem or GPRS router) to a SKF @ptitude
Observer Monitor or Analyst IMx Service. The @ptitude Observer Monitor or Analyst
IMx Service in turn can be connected to, for example, a LAN network making it possible
for several @ptitude Observer or Analyst clients to access it.
@ptitude Observer or Analyst clients can also be installed on the same computer as
@ptitude Observer Monitor or Analyst IMx Service login software. Through a general
interface, also known as ODBC (open database connectivity), it is possible to link

Introduction
IMx-S Unit
SKF Multilog On-Line System IMx-S 1 - 3
User Manual –Revision S
@ptitude Observer Monitor or Analyst IMx Service login computer to an existing
database for a control or processing system, if desired. @ptitude Observer Monitor or
Analyst IMx Service, @ptitude Observer or Analyst clients and the database can be
separated from each other as long as they are on the same network where ODBC calls
can travel freely.
It is also possible to connect different types of on-line units in the same network, for
example, IMx-S together with other IMx units and/or MasCon systems.
IMx-S Unit
Figure 1 - 2.
SKF Multilog On-line System IMx-S 16 (left) and IMx-S 32 (right).
IMx-S 16
•Up to 16 analogue channels.
•Up to 8 digital sensors, where 4 of the digital input channels are configurable for all
standard trigger sensors and 4 channels for square pulses with trigger level 12 to
24 V.
•Each IMx-S 16 unit has 8 MB flash memory with the following storage capacity:
–2 MB for firmware, configuration files, etc.
–2 MB for trend value buffer.
About 13 000 vibration trend values can be buffered.
Speed and process data use half the space of vibration.
–4 MB for spectra and time signal buffer.
About 250 spectra using 1 600 lines with phase and time signal can be
buffered.
If more lines are used, the number of spectra is reduced.

Introduction
System LED Indicators
1 - 4 SKF Multilog On-Line System IMx-S
User Manual –Revision S
If less lines are used, the number of spectra is increased.
–When the buffer gets full, the oldest data is thrown away.
IMx-S 32
An IMx-S 32 is essentially composed of two IMx-S 16s.
•Up to 32 analogue channels.
•Up to 16 digital sensors with 8 configurable digital input channels for all standard
trigger sensors and 8 channels for square pulses with trigger level 12 to 24 V.
•IMx-S 32 unit has two CPU cards. Each CPU card separately has 4 MB flash memory
with the same storage capacity of IMx-S 16.
IMx-S features
•Individual conditions for alert and danger may be set for each measurement point.
•Each channel has indicators for alert and danger. Alert and danger levels may be
controlled by machine speed or load. However, it is also possible to manually bypass
the alert and danger functionality.
•The unit's built-in hardware auto-diagnosis system continuously checks all sensors,
cabling and electronics for any faults, signal interruption, short circuits or power
failure.
Initiating an IMx-S
Initiating the IMx-S is straightforward.
•It uses an initiating program @ptitude On-line Device Configurator or Multilog IMx
Configurator tool and a laptop computer using an RS232 serial interface.
•The network configuration parameters, such as IP address, IMx identification
number, etc. are first stored in a separate configuration file, then transferred to the
IMx-S memory. These are retained in the event of power loss, so that the IMx-S can
start automatically when power returns.
System LED Indicators
An IMx-S has two system LEDs on the CPU card.
•Red SYS LED indicates system fault. On means that a system fault has been
detected.
➢Note that SYS LED is on for a short time when the system is cold
booted or re-started.
•Green PWR LED indicates the status of power. On means that the power is Ok.

SKF Multilog On-Line System IMx-S 2 - 1
User Manual –Revision S
2
Installation
The installation of an IMx-S must be carried out according to the instructions and advice
given in this manual. Any deviation from these directions can be made only after
consulting with the SKF.
Installation errors can lead to a situation where the system does not work as intended
and machinery faults go undetected. In case of questions arising during installation
contact TSG (Technical Support Group) for advice.
➢Installation errors that require the involvement of SKF personnel
to rectify, may incur additional charges.
Safety Considerations
Observe all site safety requirements including any that may be specific to the machines
or areas where the installation is being carried out. This will likely include, but not be
limited to, PPE (personal protective equipment) and a permit to work.
Important –An IMx-S unit contains circuit boards that are static sensitive.
Therefore, use appropriate precautions to prevent ElectroStatic Discharge (ESD) when
handling circuit boards.
The following are some of the ways to prevent ESD when handling or transferring circuit
boards:
•Use an ESD wrist strap
•Use a grounding mat
•Use correct packaging materials such as anti-static bags
Important - In order to fulfil fire enclosure requirements, the cabinet must always
be mounted using all four supplied mounting brackets.
When mounting the IMx-S unit, make sure that it is firmly attached at a location where it
is not unnecessarily exposed to radiant heat or strong magnetic fields.
The ambient temperature limits for the IMx-S can be found in the Environmental section
of the Technical Data.
Scenario
Before beginning an installation, it is important to assess and evaluate the location
where the system is to be installed and to plan how the installation should look after it
has been completed. For guidance on how and where to attach sensors to machines

Installation
Supply Cable
2 - 2 SKF Multilog On-Line System IMx-S
User Manual –Revision S
eig oitoed, efe to the istutio aual: Attaching Sensors for SKF Multilog
On-Line Systems.
Make a detailed layout of the equipment and note distances between components and
the networks to which it should connect. Amongst other things, consider the lengths of
all cables, their routing, where electrical power for the unit can be sourced and any
interfaces to the plant systems. Good and thorough planning is the basis for a successful
installation and system implementation.
Include specifically the IMx-S units, the @ptitude Observer Monitor or Analyst IMx
Service computer, the database server computer and all hubs/routers in the network.
Specify network configuration of each components, such as IP addresses and subnet
masks. SKF application engineers or TSG personnel will need this information in order to
assist.
Note that a CAT5/6 Twisted Pair (TP) Ethernet cable has a maximum working distance of
100 m. If longer cable lengths are needed, fibre optic cables may be used along with
appropriate converters for fibre optic to CAT5/6 (TP) Ethernet and vice versa.
When GPRS is used, the GPRS routers should be reconfigured as a part of the application
to run a lifeline connection with the Observer Monitor or Analyst IMx Service computer.
Important - Failure of this communication path will force the GPRS router to
constantly reboot and can hamper the success of the application. This is especially
important to consider when GPRS forms a part of the customers internal IP network
(VPN). In such a case, SKF must be informed of this before ordering the GPRS, so that
SKF can disable the lifeline functionality of the GPRS router.
Supply Cable
To connect IMx-S to 240 VAC or 120 VAC, the following is recommended:
•FKLK 3 x 1,5 mm2 (16 AWG) or EKLK 3 x 1,5 mm2 (16 AWG) or corresponding, with
minimum voltage requirement 300 V and temperature range of -40 to +70 ºC (-40 to
+158 ºF).
The IMx-S must be connected to protective ground/earth (PE). Refer to Mains Power for
attaching power cable to the mains power/power grid.
Important - The cross-sectional area of the PE wire must be equal or greater than
the cross-sectional area of the power wires. The PE wire should be colour coded
green/yellow. However, in some countries, other cable requirements may apply.
Important - Mains cable must be properly fixed with a cable gland to prevent the
cord from strain, twist or movement. See Cable Glands section as well.
Mains Power
Refer to Power Supply in Technical Data section for power requirements.

Installation
Mains Power
SKF Multilog On-Line System IMx-S 2 - 3
User Manual –Revision S
In order to attach power cable to the mains power grid, follow the directions below.
•First connect the green-yellow wire to the PE (protective earth) terminal.
•Connect the blue wire to the N (neutral) terminal.
•Connect the brown or black wire to the L1 (line) terminal.
Important - Make sure that the power is turned off before working with the
power cable. Touching the leads of a powered cable can cause serious injuries.
Important - In some countries, the installer must be certified to install equipment
such as an IMx-S.
Important - For permanently connected IMx-S an external all pole power switch
must be installed in order to be able to disconnect the IMx-S from the mains power
grid. The switch must be labelled "IMx-S” or siilar. O/Off positio ust e learly
marked. The switch must be located close to the IMx-S, within operator's easy reach.
Important –The fuse holder CANNOT be used as a mains power disconnect
device.
Important - In order to prevent a hazardous event, mains cable neutral (N) and
line (L1) wires must be secured together with a cable tie (for example, a nylon cable tie
CV-100K) close to the mains power connector.
Important - All externally provided equipment must be evaluated individually
and approved together with IMx-S unit regarding EMC and safety requirements (CE
and ETL). Always consult SKF before using the external mains output.

Installation
Sensor Cables
2 - 4 SKF Multilog On-Line System IMx-S
User Manual –Revision S
Figure 2 - 1.
IMx-S Mains Power and Fuse Holder.
As shown in the picture above, the incoming supply live terminal incorporates a fuse
holder that is fitted with a slow blow T2A, 250 V, 5 x 20 mm, fuse.
Sensor Cables
When routing a sensor cable, it is important that the cable is firmly fixed. The cable must
not be allowed to vibrate or oscillate, since this affects the capacitance of the cable, and
thereby the measurement result.
The sensor cable should not be routed or bundled together with supply cables since they
generate strong magnetic fields.
To connect the IMx-S to sensors, the following sensor cable type is recommended:
•Shielded, twisted pair 2 2 0,5 mm2(FKAR-PG 2 2 0.50, DUE 4002 or
corresponding)
See also Cable Glands section.
Ethernet Cable
For lengths up to 15 metres, it is recommended to use pre-fabricated Ethernet twisted
pair cable FTP type, CAT5/6.
For longer cable lengths, it is recommended to use S-FTP (screened shielded twisted
pair) Ethernet cable CAT5/6.

Installation
Ethernet Connections
SKF Multilog On-Line System IMx-S 2 - 5
User Manual –Revision S
Important - In general, all cables must be routed as far away as possible from
high voltage cabling. If this cannot be done, care should be taken to use high quality
shielded cables, such as S-FTP (screened shielded twisted pair) CAT6 for the network. In
difficult cases, it is the safest to use fibre optic cables.
Ethernet Connections
The IMx-S unit data communications are compliant with the Ethernet standard 10/100
Mbit (half- and full-duplex).
An IMx-S has two, RJ45, Ethernet ports which work like an internal network switch. The
Ethernet TP cable should be connected to one of these ports.
Both Ethernet ports have auto detection of crossover or straight through Ethernet cable
connection. Basically, an IMx-S has a built-in 2-port Ethernet switch. It is possible to
connect several IMx-S units in a daisy chain with up to 8 units in a single cable layout.
There are two LEDs on each RJ45 connector.
•Green LED is the Ethernet link indicator that lights up when the system is correctly
connected to another network device.
•Yellow LED is the Ethernet traffic indicator that flickers whenever there is traffic on
the network.
Cable Glands
If cable shields are to be grounded to the IMx-S unit, then metallic EMC type cable
glands with a 360-degree shield connection are recommended for all cable types except
the mains and communication cable.
•Avoid ground loops via the sensor cables by preferably connecting the shield at, and
only at, the IMx-end.
•Ensure the metal/EMC cable gland has a good 360-degree connection to the IMx-S
enclosure (nut or washer must penetrate any paint or coating on the box).
Important - All unused cable entries must be closed with blind plugs. All cable
glands and blind plugs must be made of material with fire protection V-1 or better. All
cable glands must also meet or exceed IP65 so as to maintain the IP rating of the
enclosure.

SKF Multilog On-Line System IMx-S 3 - 1
User Manual –Revision S
3
Unit Configuration
In general, when referring to DIP switch settings 0 means Off and 1 means On:
Table 3-1: DIP switch setting definition.
DIP Switch Setting
Definition
0
OFF
1
ON
Analogue Inputs
The figure below shows the screw terminal connections for the IMx-S.
Important - The sensor shield should be connected either to the sensor or to the
IMx-S unit depending on the cable and the sensor type. To avoid ground loops the
sensor shield should be connected only at one end.
Figure 3 - 1.
IMx-S Terminal Connection, Standard Accelerometer.
The IMx-S I/O board along with the corresponding analogue terminal list are shown
below.

Unit Configuration
Analogue Inputs
3 - 2 SKF Multilog On-Line System IMx-S
User Manual –Revision S
Figure 3 - 2.
IMx-S I/O Board, Analogue Inputs.
Table 3-2: Analogue terminal list.
The DIP switch settings for connected analogue sensors must be applied according to
the table below.
Table 3-3: DIP switch settings for analogue sensors.
Signal
Terminal
DIP Settings
position: 123456
Standard
accelerometer
(2-wire, IEPE)
N.C.
+ Signal/Pwr
Com.
Pwr
A
B
100110
Voltage source
N.C.
+ Signal
Com.
Pwr
A
B
000000
4–20 mA source
N.C.
+ Signal
–Signal
Pwr
A
B
000001
B-sensor (4–20 mA
output)
+24 V
Signal
Com.
Pwr
A
B
100101
Eddy current probe
(–24 V)
–24 V
Signal
Com.
Pwr
A
B
011000
Voltage powered
sensor (max 35 mA)
+24 V
Signal
Com.
Pwr
A
B
100100
4–20 mA (IMx
powered)
+ Signal
–Signal
N.C.
Pwr
A
B
100101
N.C. = Not Connected
DIP switch setting 1 = ON, 0 = OFF

Unit Configuration
Digital Inputs
SKF Multilog On-Line System IMx-S 3 - 3
User Manual –Revision S
At maximum ambient temperature, the total sensor power from all inputs must not
exceed:
IMx-S 16 10 W
IMx-S 32 10 W (at 60 ˚C [140 °F] only IEPE sensors are recommended)
At lower temperatures more total sensor power is allowed; please contact TSG or an SKF
application engineer.
Important - Do NOT change DIP switch settings while the IMx-S unit is powered,
as this may cause damage and void warranty.
Important - Before powering the IMx-S unit, make sure that DIP switch settings
are properly set to match the recommendations for the connected sensors. Incorrect
settings may cause permanent damage to the IMx-S unit.
Digital Inputs
The IMx-S I/O board along with the corresponding digital terminal list are shown below.
Figure 3 - 3.
IMx-S I/O Board, Digital Inputs.
Table 3-4: Digital terminal list.
Digital inputs 1 to 4 (Dig1 to Dig4) are configurable via DIP switch settings. These must
be set according to the table below.

Unit Configuration
Digital Inputs
3 - 4 SKF Multilog On-Line System IMx-S
User Manual –Revision S
Table 3-5: DIP switch setting for digital sensors.
Signal
Terminal
DIP Settings
position: 1234
(with I/O-board
version less
than v1.24)
DIP Settings
position: 1234
(with I/O board
v1.24 or greater,
with a hole in front
panel for DIP21)
Tacho 2-wire
(24 V internally powered,
max 30 mA)
+
–
N.C.
A
B
O
1010
1011
Tacho 3-wire NPN
(24 V internally powered,
max 30 mA)
Brown (+24 V)
Black (Signal)
Blue (0 V)
A
B
0
0100
0101
Tacho 3-wire PNP
(24 V internally powered,
max 30 mA)
Brown (+24 V)
Black (Signal)
Blue (0 V)
A
B
0
1010
1011
Pulse 12–24 V
(external power)
+
–
N.C.
A
B
O
0100
0101
Pulse TTL
(external power)
N.C.
+
–
A
B
0
1010
1010
N.C. = Not Connected
DIP switch setting 1 = ON, 0 = OFF
DIP position 4 has no effect on the older I/O board (less than V1.24).
Digital inputs 5 to 8 (Dig5 to Dig8) are non-configurable and sensor power is from
external source.
They are only used for externally powered signals with signal level of 12 to 24 V, square
wave signal.
Table 3-6: Digital inputs 5 to 8 terminal list.
Signal
Terminal
Pulse 12–24 V
(external power)
+
–
A
B

Unit Configuration
RS485 Communication
SKF Multilog On-Line System IMx-S 3 - 5
User Manual –Revision S
RS485 Communication
Twisted pair shielded cable shall be used.
Important - Connect the shield only at one end to avoid ground loops.
The cable connection should be according to the following:
Table 3-7: Cable connection.
IMx-S
RS485 Equipment
RS485 A Out
A
RS485 B Out
B
If the IMx-S unit is at the end or beginning of the RS485 Bus, activate the built-in
termination resistor by setting DIP21 according to the table below. DIP21 can be
accessed after the front panel has been taken off. It is located below the Dig3 DIP switch.
➢On newer systems there is a hole in the front panel for DIP21 (no
need to remove front panel).
Table 3-8: DIP21 functionality.
DIP21 settings
position: 1234
Functionality with I/O board version less than
v1.24 (DIP21-switch with 4 positions)
0100
Termination resistor enabled RS 485
0000
Termination resistor disabled RS 485
DIP21 settings
position: 123456
Functionality with I/O board v1.24 or greater
(DIP21-switch with 6 positions)
011010
Termination resistor enabled
001010
Termination resistor disabled
Figure 3 - 4.
Front Panel with DIP21 Hole (I/O board v1.24 or Greater).
This 2-wire RS485 communication supports Modbus RTU protocol in which the IMx-S can
be configured as a Modbus master or as a Modbus slave device. For more information
regarding RS485/Modbus and the different configurations that are supported, refer to
the appropriate user manual, "Modbus for SKF IMx and @ptitude Observer" o Modbus
for SKF IMx and @ptitude Analystad also the appliatio ote Geeal Modus
Protocol Considerations for IMx-Devices" .

Unit Configuration
Relay Driver Outputs
3 - 6 SKF Multilog On-Line System IMx-S
User Manual –Revision S
Relay Driver Outputs
The IMx-S I/O board has a total of five, relay driver outputs, the board along with the
corresponding relay terminal list are shown below.
Figure 3 - 5.
IMx-S I/O Board, Relays.
Table 3-9: Relay output connection list.
Software Controlled Relay Outputs
Each IMx-S 16 has four and IMx-S 32 has eight software controlled relay driver outputs
labelled as Dig1 OUT through Dig4 OUT (see terminal list above). These relay driver
outputs can be connected to relays as shown in the figure below.
Figure 3 - 6.
Relay Driver Output Connections.
Note that terminals Dig +12V always have the voltage +12 V, whereas terminals Dig1
OUT to Dig4 OUT are low side drivers known as open collectors.