Acromag Bus Works 900EN Series User manual

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Bus Works® 900EN Series
Modbus TCP/IP 10/100MB Industrial Ethernet I/O
Modules
Model 989EN-4016 16 CH DI/O w/ Event Counters
(Industrial Grade)
Model 989EN-4C16 16 CH DI/O
(Commercial Grade)
USER’S MANUAL
ACROMAG INCORPORATED Tel: [phone]
30765 South Wixom Road Fax: [phone]
Wixom, MI 48393-2417 U.S.A. Email: [e-mail]
Web: http://www.acromag.com
Copyright 2009-2014, Aroma, Inc., Printed in the USA.
Data and specifications are subject to change without notice. 8500805K

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
2
IMPORTANT SAFETY CONSIDERATIONS
You must consider the possible negative effects of power, component,
wiring, sensor, or software failure in the design of any type of monitoring or
control system. This is very important where property loss or human life is
involved. It is important that you perform satisfactory overall system design
and it is agreed between you and Acromag, that this is your responsibility.
GETTING STARTED
MOUNTING AND DIMENSIONS……………………………..
3
CONTROLS & INDICATORS..………………………………..
3
ISOLATION BARRIERS..……………………………………...
3
CONNECTIONS………………………………………………...
4
DIN-Rail Mounting And Removal…………………….
4
Network…………………………………………………...
4
Power……………………………………………………...
6
Excitation…………………………………………..........
7
Earth Ground..………………………………….……….
7
Digital Inputs…………………………………………….
7
Digital Outputs..…………………………………………
11
WEB BROWSER………………………………………...........
14
Home Page………………………………………………
14
Password Configuration Page.………………..........
15
Network Configuration Page………………………….
16
I/O Configuration Page..……………………………….
18
I/O Configuration Page Help…………………………..
18
Test Page…………………………………………………
22
Counter Configuration Page………………………….
23
Counter Test Page………………………………………
26
Utility Page……………………………………………….
27
I/O Self Test Help………………………………………..
29
TROUBLESHOOTING…………………………………………
29
Diagnostics Table……………………………..………..
29
Getting Out Of Trouble…………………………………
32
Trouble Browsing Your Module?.............................
32
TECHNICAL REFERENCE
KEY FEATURES………………………………………………..
33
HOW IT WORKS………….…………………………………….
34
ABOUT MODBUS TCP/IP….…………………………………
36
IP Addressing…………..……………………………….
38
Dynamic Host Configuration Protocol………………
39
Domain Name System (DNS)………………………….
40
MODBUS REGISTERS………………………………………..
40
Register Functions……………………………………..
40
Register Mirroring……….……………………………...
41
Data Types……………………………………………….
42
Register Map……………………………………………..
43
SPECIFICATIONS……………………………………………...
56
Model Numbers….………………………………………
56
Digital Inputs…………………....……………………….
56
Digital Outputs………………..…………………………
58
General Specifications…………………………………
59
Enclosure and Physical………………………………..
59
Agency Approvals…..…………………………………..
60
Environmental…………………………………………...
60
Ethernet Interface……………………………………….
61
Controls & Indicators…………………………………..
61
ACCESSORY CABLES……..…………………………………
62
Patch Cable & Crossover Cable………………………
63
REVISION HISTORY…………………………………………..
65
TABLE OF
CONTENTS
Symbols on equipment:
Means “Refer to User’s
Manual (this manual) for
additional information”.
The information of this manual
may change without notice.
Acromag makes no warranty
of any kind with regard to this
material, including, but not
limited to, the implied
warranties of merchantability
and fitness for a particular
purpose. Further, Acromag
assumes no responsibility for
any errors that may appear in
this manual and makes no
commitment to update, or
keep current, the information
contained in this manual. No
part of this manual may be
copied or reproduced in any
form without the prior written
consent of Acromag, Inc.
For additional information,
please visit our web site at
www.acromag.com and
download our whitepaper 8500-
765, Introduction to Modbus
TCP/IP, or 8500-648,
Introduction to Modbus.
This product is compatible
with Internet Explorer 7 and
Mozilla Firefox v2.0
Windows® is a registered
trademark of Microsoft
Corporation.
!

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
3
The push-button is used to toggle the module into or out of Default Mode.
In Default Communication Mode, the module assumes a fixed static IP
address of “128.1.1.100”, a default subnet mask of “255.255.255.0”, a default
username of “User”, and a default password of “password”. To activate it,
hold down the DFT button on the front panel for five seconds (until the ST
LED blinks on/off slowly. To disable this feature, hold the DFT button for
another five seconds or until the ST LED stops blinking.
MOUNTING AND
DIMENSIONS
Unit mounts to “T” type DIN
rails (35mm, type EN50022).
Units may be mounted side-
by-side on 1-inch centers.
WARNING: IEC Safety
Standards may require that
this device be mounted within
an approved metal enclosure
or sub-system, particularly for
applications with exposure to
voltages greater than or equal
to 75VDC or 50VAC.
CONTROLS &
INDICATORS
Green Run LED is ON if power
is on and will blink in “wink” ID
mode.
Yellow ST LED blinks ON/OFF
slowly if module is in default
communication mode, and
blinks rapidly if a watchdog
timeout has occurred.
Green LINK LED is ON if auto-
negotiation has successfully
established a connection.
Yellow ACT LED signals PHY
network Activity (busy).
ISOLATION BARRIERS
Dashed Lines denote isolation
barriers.
The I/O circuit, network, and
power circuits are isolated
from each other for safety and
noise immunity.
44 41 36 33
PWR
NETWORK
TB4
13
CH 2
16
RTN
21
CH 5
I/O
EXC
24
CH 8
TB1
CH13 CH10
RTN
GND
46 4345
RX
I/O
42 35
DC-
DC+
32 313434
TB1
11 1412
CH 1 CH 0
CH 3
TB2
2215
TX
CH 6 CH 4
TB4
TB3
25 2623
CH 7 CH 9
RTN
DC
PWR
RTN
CH12 CH14
TB2
CH11
CH15
EXC+
DIGITALI/O
DIGITAL IN or OUT
DIGITALI/O
EXC
DIGITAL IN or OUT
DIGITALI/O
DIGITAL IN or OUT
TRANSFORMER
3.3V
TB3
989EN
ISOLATION
DIAGRAM
TRANSFORMER
DEF
46 44 43 41 36 35 33
DC-
32
TB1
11
CH 0 RTN
13
CH 2 CH13
14
CH 3 CH12
RTN
16
CH10
TB4
21
CH 5 RTN
22
CH 6 CH15
24
CH 8 GND
25
CH 9
LINK
ACT
ST
45
I/O
42
PWR
DC+
3134
L
C
RUN
3.75 (95.3)
TB1
12
CH 1 CH14
TB4
TB2
TB2
15
CH 4 CH11
TB3
2623
CH 7
RTN
EXC+
TB3
4.68 (118.9)
3.90
(99.1)
ETHERNET
DIGITAL IN or OUT EXC
2.34 (59.4)
DIGITAL IN or OUT
Acromag
DIGITAL IN or OUT
1.05
(26.7) "T"RAILDINMOUNTING
DINEN50022,35mm 4.35
(110.5)
NOTE:DimensionsAreINCHES(MILLIMETERS).
MODEL989ENENCLOSURE DIMENSIONS
MODEL 989EN-4016
MODEL 989EN-4C16
11
46
14
43
22
35
25
32
ST
RTN
CH12
CH15
GND
DC-
CH 0
CH 3
CH 6 CH 9
LINK
TB1
13 1612 15
44 4145 42
TB2
21 2423
3336 34
26
31
DEF
ACT
TB1
CH13
CH11
CH14
CH10
TB2
EXC+
RTN
I/O EXC
DC+
TB3
TB4
CH 2 CH 1
RTN
CH 4 CH 5 CH 8
CH 7
TB3
RTN
ETHERNETETHERNET
RUN
TB4
RJ45 ETHERNET
CONNECTOR
REMOVABLE
AcromagAcromag
DIGITAL IN or OUTDIGITAL IN or OUT
Model 989EN-4016
Model 989EN-4C16
PWR
DIGITAL IN or OUT
(PLUG-INTYPE)
TERMINAL BLOCKS
RUN/PWRLED(GREEN)
MODULESTATUS
LED(YELLOW)
DEFAULT ADDRESS
PUSHBUTTONSWITCH:
PRESSTOSET
DEFAULT ADDRESS
ETHERNET LINK(GREEN)
ANDACTIVITYLED(YELLOW)

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
4
1
8
7
5
4
2
1
100M
100M
CLIP
8
6
3
CABLE
8
1
10Base-T CAT 5UTP/STP
Not Used
Not Used
Not Used
Not Used
Receive-
Receive+
RJ-45CONNECTOR
SPEED
PIN
DISTANCE
Transmit -
Transmit +
MDI-XWIRING
100Base-T CAT 3, CAT 4, orCAT 5 UTP/STP
NoteCrossoverConnections
MINIMUMRECOMMENDEDCABLE
Not Used
Not Used
Not Used
Not Used
Transmit -
Transmit + ETHERNET PORT
RJ45 MDI ANDMDI-X CONNECTIONS
Receive-
Receive+
MDI WIRING
45 44 42 41 33
DC+
31
TB4
12 13 15 16 21 23 24 26
TB1
GND
46 43
PWR
DC-
32
11 14 22
TB3
25
PUSH
TB2
"T"TYPE
DINRAIL
PUSH SCREWDRIVER ASSHOWN
TOTILTANDLIFTMODULEOFFRAIL
RemoveTerminalBlocksOnThis
SideToProvideClearance
Any Series9XXEN Ethernet Module
MODULEREMOVAL
FROMDINRAIL
PRYWITHSCREWDRIVER
INSERTEDINSLOTHERE
(DONOTTWISTTOAVOID
DAMAGINGPLASTICTAB)
USEYOURFINGER TOAPPLY
DOWNWARDPRESSUREHERE
ASYOULIFTANDTILTMODULE
TOREMOVEITFROMRAIL
When attaching the module to the
T-type DIN rail, angle the top of the
unit towards the rail and locate the
top groove of the adapter over the
upper lip of the rail. Firmly push the
unit towards the rail until it snaps into
place. To remove, first separate the
input terminal block(s) from the
bottom side of the module to create a
clearance to the DIN mounting area.
Next, while holding the module in
place from above, insert a
screwdriver into the lower arm of the
DIN rail connector and use it as a
lever to force the connector down
until the unit disengages from the rail
(do not twist the screwdriver to avoid
damaging plastic).
The Ethernet port of this unit is wired MDI-X by default, but includes
automatic crossover (the Ethernet port of your PC is typically wired MDI).
Thus, you can use either a straight-through or crossover cable to connect
this device directly to a PC, Ethernet switch, or another unit.
CONNECTIONS
DIN-Rail
Mounting & Removal
Network
For 100Base-TX systems, at a
minimum, use data grade
Unshielded Twisted-Pair
(UTP) wiring that has a 100Ω
characteristic impedance and
meets the EIA/TIA Category 5
wire specifications.
It is recommended that you
use a CAT-5 cable to connect
this device to your PC.
For 10Base-T systems, you
may use Category 3, Category
4, or Category 5/5E UTP/STP
cable.
In either case, you are limited
to 100 meters between any
two devices.

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
5
1
1
3
6
1
6
2
3
1
8
281
8
8
1
PINS: 1TO 3
2TO 6
3TO 1
6TO 2
RJ45(ClipSideDown) RJ45(ClipSideDown)
FOR DIRECTPC TO
ETHERNETMODULE
CONNECTIONS
CROSSOVER CABLE
FOR MDI TO MDI
OR MDI-X TO MDI-X CROSSOVER
CONNECTIONS
From the factory, the 989EN unit has a default IP address setting of
128.1.1.100, and a class C subnet mask of 255.255.255.0. This defines a
restricted default address domain that your current network cannot address
directly, unless you first create an exclusive subnet targeted to the 989EN.
This typically involves a process by which you either change the address of
your current network interface card (which will temporarily disable it from
your own network), install a second network interface card, or obtain an
unused PC or laptop with a NIC installed. In any case, you must set the
address of your network interface card to an address within the default
address domain. That is, an address from 128.1.1.0 to 128.1.1.255, except
for 128.1.1.100, which is the default address of the 989EN itself. Once you
are able to address the unit at its default address, you can then reconfigure
its IP address setting to an address more meaningful to your own network.
Application Note 8500-734 is downloadable from the Acromag website and
covers this process in greater detail.
DEF
ACT
ST
RUN
AcromagAcromagAcromag
ETHERNETETHERNET
LINK
HOSTPC
(UseRegular or Crossover Cable)
CAT-5UTPCABLE
UPTO100METERS
Acromag 989EN-4016
EthernetModule.
Theethernetportofthis
moduleiswiredMDI-X,but
supportsautomaticcrossover.
HOSTPCCONNECTEDDIRECTLYTOAMODULE
Refer to the Accessory Cables section at the back of this manual for more
information on accessory cables including patch and crossover cables
available from Acromag and other vendors.
TIP: You can significantly enhance the EMI/RFI performance of your
network connections by using Category 5E STP cable (Shielded Twisted
Pair) with shielded RJ45 plug connectors. This will also help to protect your
installation from damage due to ESD (Electro-Static Discharge). The use of
shielded cable is strongly recommended for installations in harsh industrial
environments and/or in the presence of strong electrical fields.
CONNECTIONS
Network
A crossover cable simply
connects the differential
transmit pair on each end, to
the receive pair on the
opposite end.
Use a standard (direct) cable
when connecting to a hub or
switch port, which are
generally wired MDI-X.

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
6
You can use an Ethernet switch or switching hub to build a network of
Ethernet modules, similar to that shown below. This drawing shows how to
network-connect these modules to a 5-port Ethernet switch (Acromag Model
900EN-S005). Note that the 900EN-S005 switch includes automatic
MDI/MDI-X crossover and straight-through or crossover cable(s) may be
used, but it is generally not good practice to use crossover cables when
connecting to an auto-crossing switch.
✓Connect 18-36V DC to the power terminals labeled DC+ & DC-.
Observe proper polarity. For supply connections, use No. 14 AWG
wires rated for at least 75C. CAUTION: Do not exceed 36VDC peak.
+TB3
I/O EXC PWR
36
RTN
EXC+
34
GND
33 31
DC+
35
TB3
CH15
32
DC-
CAUTION: Risk of Electric Shock –More than one disconnect switch may
be required to de-energize equipment before servicing.
IMPORTANT –External Fuse: If unit is powered from a supply capable of
delivering more than 1A to the unit, it is recommended that this current be
limited via a high surge tolerant fuse rated for a maximum current of 1A or
less (for example, see Bel Fuse MJS1).
CONNECTIONS
Network
Power
Note: Current draw figures do
not include excitation current.
Voltage
Current
(Typ)
Current
(Max)
18 VDC
66 mA
73 mA
24 VDC
49 mA
54 mA
36 VDC
33 mA
37 mA
X5
X4
X2
X1
P1
X3 X4
RUN
X3
S1 S2 36 35
DC-
33
DC+
32
ST
TB4 TB3
RUN
X1
X5
X2
LINK
ETHERNETETHERNET
LINK
LINK
DE F
ACT
RUN
AcromagAcromagAcromag
ETHERNETETHERNET
AcromagAcromagAcromag
PGM
PORT
GND
DC+
POW E R
34 31
DE F
ACT
ST
DE F
ST
ACT
ETHERNETETHERNET
AcromagAcromag
DE F
ACT
Acromag
ETHERNETETHERNET
LINK
ST
ETHERNETETHERNET
RUN
RUN
HOSTPC
DIP SW S 1/S 2
CFG OPTIONS
CAT-5UTPCABLE
UPTO100METERS
(StraightThroughor Crossover Cable)
CAT-5UTPCABLE
UPTO100METERS
(StraightThroughor Crossover Cable)
Order Acromag CableModel 5035-355
AcromagAcromagAcromag
AcromagAcromagAcromag
CAT-5UTPCABLE
UPTO100METERS
PUSH TO RESET
900EN-S005
(StraightThroughor Crossover Cable)
CAT-5UTPCABLE
UPTO100METERS
CAT-5UTPCABLE
UPTO100METERS
(StraightThroughor Crossover Cable)
Acromag 900EN-S005
5-PortEthernetSwitch
or equivalent.
Theethernetportofthis
switchareautomaticMDI/MDI-X
crossover anddonot require
crossover cables.
(StraightThroughor Crossover Cable) Acromag 989EN-4016
EthernetModule.
Theethernetportofthis
modulesupports
automaticMDI/MDI-X
crossover,andis wired
MDI-X
USEOFAN ETHERNETSWITCHTONETWORK
AHOSTPCTOMORETHAN ONEMODULE
Acromag offers astraight-throughpatchcable(Model 5035-355),or a
crossover cable(Model 5035-360) for usewithSeries9xxEN modules.
Note: ThisMDI-to-MDI-Xconnectiondoesnot requiretheuseofacrossover cable.

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
7
+
TB3
I/O EXC PWR
36
RTN
EXC+
34
GND
33 31
DC+
35
TB3
CH15
32
DC-
✓Connect 8-28V DC to the excitation terminals labeled EXC+ and RTN.
Optionally you can jump DC input power to Exc+ as long as it does not
exceed 28VDC. Observe proper polarity. For supply connections, use
No. 14 AWG wires rated for at least 75C. CAUTION: Do not exceed
35VDC peak.
IMPORTANT: You MUST connect an excitation supply to the excitation
(EXC) and Return (RTN) terminals in order to operate I/O.
CAUTION: Risk of Electric Shock –More than one disconnect switch may
be required to de-energize equipment before servicing.
✓Connect Earth Ground as shown in the connection drawings on previous
page. Additionally, connect the GND terminal (TB3-33) to earth ground.
The ground connections noted are recommended for best results. If
sensors are already grounded, use caution and avoid making additional
ground connections which could create ground loops.
The module housing is plastic and does not require its own earth
ground.
✓Connect digital input signals to the input terminals as shown on the
following page. The tandem outputs must remain OFF in order to drive
inputs externally.
To drive the inputs from an external source, you must turn the
corresponding outputs OFF, or the output channel will be in contention
with your external input signal.
IMPORTANT: You MUST connect an excitation supply to the excitation
(EXC) and Return (RTN) terminals in order to operate I/O. External
excitation should be from 8 to 28V and must provide 36mA (288mA
peak), plus any output load current.
Inputs source wetting current to sense switch closure. By default, this
current is set to switch to 16mA for 20ms after crossing the 4V input
threshold, then return to 2mA continuous. The higher level of initial
current will help to prevent oxide buildup on external switch contacts.
The current can also be set to only source 2mA continuous. This
current can also be turned OFF by tri-stating the port inputs.
CONNECTIONS
Excitation
Note: Excitation can be
optionally be sourced from the
input power supply.
CAUTION: Excitation
voltages greater than 28V do
not guarantee I/O operation.
Make sure that if you jump
input power to excitation, that
it is less than or equal to
28VDC.
Earth Ground
Warning: To comply with
safety and performance
standards, use shielded cable
and connect earth ground as
noted. Failure to use good
wiring and grounding practices
may be unsafe and negatively
affect performance.
Digital Inputs
Inputs are active-low, with 4V
thresholds (3.7-4.3V range).
Input connections require an
external excitation source.
Limit input voltages to less
than 31VDC maximum.
Inputs include wetting current
pull-ups to sense switch
closure, which also allows the
open-drain output to operate
without adding a pull-up.

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
8
5V
INP
V+
RTN
EXC
5V
RTN
or
+
I/O (INT PULL-UP)
RTN
TANDEM OUTPUTMOSFETISOFF.
EXCITATION ISREQUIRED(8-28V).
INP
EXT
EXC 5.5V MIN
IF INPUTSARENOTTRI-STATED,EXTERNALPULLUPISOPTIONAL.
EXTERNAL5VLOGICMUSTBEPULLEDUPABOVE4VINPUTTHRESHOLD.
IF INPUTSARETRI-STATED,EXTERNALPULLUPISREQUIRED.
SIMPLE DIGITALINPUTCONNECTIONS
I
+
I/O
EXC
(INT PULL-UP)
EXT
EXC 5.5V MIN
RTN
TANDEMOUTPUTMOSFETISOFF.
N.C.
EXCITATION ISREQUIRED(8-28V)
SIMPLIFIEDI/O(ONEPORTCHANNEL)
N.O.
CONTACTSASSHOWN:
LOGIC "1" = ON = CLOSED
LOGIC "0" = OFF = OPEN
DRY-CONTACTRELAY CONNECTIONS - NORMALLY OPENORCLOSED
WETTINGCURRENTIS16mAFOR20msAFTER INPUTCROSSES4VTHRESHOLD,
THEN RETURNSTO2mACONTINUOUS.
I+
N.O.
N.C.
RTN
I/O (INT PULL-UP)
5.5V MIN
EXC EXT
EXC
EXT PULL-DOWN MAY BE REQUIRED
FOR SOME APPLICATIONS.
OPEN-LOADCURRENT.
TANDEMOUTPUTMOSFETISOFF.
PORTINPUTSARETRI-STATED TOTURNOFFWETTINGCURRENTPULL-UPS
NOTE: ITISACCEPTABLETOUTILIZETHE24VDCPOWERTOTHEUNITTO
DRIVETHEEXCITATIONTERMINALAND/OR THECONTACTEXCITATION.
DONOTALLOWUNUSEDTRI-STATEDINPUTSTOFLOATORTURNONOUTPUT
ANEXTERNALPULL-DOWN RESISTORMAYBEREQURIEDFOR SOMEAPPLICATIONS.
EXCITATIONISREQUIRED (8-28V)
SIMPLIFIEDI/O(ONEPORTCHANNEL)
DRY-CONTACTRELAY CONNECTIONS- NORMALLY OPEN
ORCLOSEDWITHEXTERNALSERIESCONTACTEXCITATION
CONTACTSASSHOWN:
LOGIC"1" =ON=OPEN
LOGIC"0" =OFF= CLOSED
Refer to the examples that follow for other types of input connections.
CONNECTIONS
Digital Inputs
Normally Open (N.O.) or
Normally Closed (N.C.) Dry
Contact Relay.
Inputs use wetting current to
sense external contact state.
This current normally goes to
16mA when the input
descends below the 4V
threshold, for 20ms, then
returns to 2mA continuous.
Normally-Closed Dry Contact
Relay with Series Contact
excitation
Do not exceed 31V at the
inputs.

BusWorks® Model 989EN User’s Manual Modbus TCP/IP Digital I/O & Counters
_________________________________________________________________________________
_______________________________________________________________________________________
Acromag, Inc. Tel:[phone] Fax:[phone] Email:[email protected] http://www.acromag.com
9
INP
+
RTN
EXC
V+
I/O (INTPULL-UP)
5.5VMIN
EXT
EXC
EXTERNAL DRIVER MUSTBE PULLED UP ABOVE 4V INPUTTHRESHOLD.
EXTERNAL PULLUP IS ADDEDHERE TO INCREASE CURRENT.
IF NOTTRI-STATED, INTERNAL WETTING CURRENTIS SETTO 2mA.
INPUTS MAY OPTIONALLY BE TRI-STATED TO TURNOFF WETTING CURRENT.
TANDEM OUTPUTMOSFETIS OFF.
EXCITATION IS REQUIRED (8-28V).
SOLID-STATE RELAYMONITOR
TIP: You can increase wetting currents by paralleling I/O channels, or by
adding an external pull-up resistor from I/O to an external excitation source.
TIP: Unused tri-stated inputs can be pulled to the ON state if you also
enable the tandem output open-load detection (this adds 50uA pull-downs in
the output OFF state).
Note that wetting currents are slightly lower than 2mA/16mA for excitation
voltages below 8V. They will also vary slightly with the number of channels
turned ON. Use external excitation equal to or above 8V to properly regulate
this current to 2mA/16mA.
V
ON
+
_RTN
EXC
CNT
Generator
Frequency
8-28V
OPEN-DRAIN OUTPUTS SHARE RETURN.
EXT
EXC
SHIELDED
CABLE
OFF
EXCITATION IS REQUIRED. EXTERNAL EXCITATION IS 8V MIN TO 31V MAX.
PIN CAN BE USED AS COUNTER OR DIGITAL I/O LINE
EVENT COUNTER IS RATED FOR FREQUENCIES 0-150HZ
FREQUENCYINPUT CONNECTION
CONNECTIONS
Digital Inputs
Solid-State Relay (SSR)
Monitoring
Tri-stating the inputs will turn
off the wetting current pull-ups
and the input will then act like
a high-impedance comparator
with a 4V logic threshold. If tri-
stated inputs are left
unconnected, the I/O channels
float and will need to be tied
OFF to properly register the
OFF state (you could
optionally use output open-
load detection to pull-down
unused tri-stated inputs—see
TIP below).
Frequency Input Connection
(989EN-4016 Only)
Input Event Counters are rated
from 0 to 150 Hz with signal
voltages from 0 to 28 VDC (4V
Threshold). Your excitation
voltage determines your input
voltage signal range
maximum. These 32-bit
counters are additionally
equipped with a programmable
debounce, up/down counting,
selectable edge, and count
auto-restore after a power
reset.

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10
+
-
+
I
EXT
EXC
RTN
EXC
I/O (INTPULL-UP)
5.5VMIN
INPUTS ARE TRI-STATED IN THIS EXAMPLE
TANDEMOUTPUT MOSFET IS OFF.
EXCITATION IS REQUIRED (8-28V)
SIMPLIFIED I/O (ONE PORT CHANNEL)
3-WIRESOURCINGPROXIMITYSENSOR
R = EXTERNAL RESISTOR, WHICH MAY BE NEEDED IF DEVICE REQURIES MORE
THAN 2mA TOOPERATE OR INPUTS ARE TRI-STATED
OFF
ON
V8-28V
OPEN-DRAINOUTPUTSSHARERETURN.
RTN
CNT
EXC EXT
EXC
PINCAN BEUSEDASCOUNTERORDIGITALI/OLINE
EXCITATIONISREQUIRED. EXTERNALEXCITATIONIS8VMINTO31VMAX.
EVENTCOUNTERISRATEDFORFREQUENCIES0-150HZ
FREQUENCY INPUTCONNECTION(DRY CONTACT)
SHIELDED
CABLE
Note –Counters will auto restore count values from non-volatile memory
after a power loss. This option can be disabled through the webpage or via
Modbus if desired.
+
I
EXT
EXC
RTN
EXC
N.O.
CONTACTSASSHOWN:
LOGIC"1" = ON = CLOSED
LOGIC"0" = OFF = OPEN
I/O (INT PULL-UP)
5.5V MIN
TANDEM OUTPUT MOSFET ISOFF.
EXCITATION ISREQUIRED (8-28V)
SIMPLIFIEDI/O(ONEPORT CHANNEL)
2-WIRE NAMUR/ PROXIMITY SENSORNORMALLY OPEN
R = EXTERNALRESISTOR, WHICH MAYBENEEDED IFDEVICEREQURIESMORE
THAN2mATOOPERATE
CONNECTIONS
Digital Inputs
Dry Contact Frequency Input
Connection (989EN-4016
Only)
To accommodate dry-contact
relays, counters are equipped
with programmable debounce.
The debounce time can be set
from 0 to 65535 ms. The
debounce time represents the
amount of time an input must
remain stable to increment the
count.
2-Wire Namur/Proximity
Sensor Connection (989EN-
4016 Only)
To accommodate
Namur/Proximity sensors, the
989EN can source current to
drive the sensor. If the device
requires more than 2mA to
operate, an external pull-up
can be added between
Excitation and the Counter
Channel to ensure proper
current.

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✓Connect your output load to the output terminals as shown below.
A
BON
V
V
DEXT
EXC
D L
TB3
OFF
ON
V
0-28V
8-28V
L
A
OFF
RTN
TB1
CH03
CH02
CH01
CH00
FOR EVENGREATEROUTPUTDRIVE,
CONNECTANINTERPOSINGRELAY.
NOTE: ITISACCEPTABLETOUTILIZEDCPOWERTOTHEUNIT
TOALSODRIVETHEEXCITATIONTERMINALAND/OR THELOAD.
EXCITATIONISREQUIRED. EXTERNALEXCITATIONIS8VTO31VMAX.
OUTPUTSMAYTEMPORARILYSHUTDOWNFOREXCITATIONOVERVOLTAGESABOVE28V.
DIGITALOUTPUTCONNECTIONS
Note - You must connect port excitation to operate I/O. Your excitation
voltage should be greater than your load voltage. Outputs may temporarily
shut down for excitation voltages over 28V, or load voltages greater than
31V.
IMPORTANT –Add Protection With Inductive Loads: Outputs should
include reverse-bias shunt diodes to help protect the output switch from
damage due to the high reverse-bias voltages normally generated when
switching inductive loads. You should add external protection near the
inductive load to prevent these transients from being sent along the
connection wires. Place a diode (1N4006 or equivalent) across an inductive
load with the cathode to (+) and the anode to (-).
LOAD GROUNDING: If your load is connected at some distance from the
unit, or your load currents are high, earth grounding the return lead should
be done local to the I/O terminals to allow the built-in transient protection to
effectively shunt to earth via a low impedance path not affected by IR losses.
Refer to the examples below for other types of output connections.
R
I/O
EXT
EXC
LED
EXC
ON
SSR
V8-28V
RTN
OFF
(N.O.)
TO
LOAD/LINE
TO
LOAD/LINE OPEN-DRAINOUTPUTSSHARERETURN.
EXCITATION ISREQUIRED. EXTERNALEXCITATION IS8VMINTO31VMAX.
SOLID-STATE RELAY (SSR) ORLEDDRIVERCONNECTIONS
CONNECTIONS
Digital Outputs
Outputs are the open-drains of
mosfet switches and are
intended for DC current-
sinking applications only.
Note: Outputs will turn OFF
(open) following a software
reset or power interruption to
the unit.
Do NOT connect outputs to
voltages greater than 31V or
damage to the I/O port may
result. The 31V limit is the
working voltage limit of the
built-in transient voltage
suppressors at each I/O
channel.
Solid-State Relay (SSR) or
LED Driver
You should also consider
whether open-load detection
feature should be enabled, as
this can pull 50uA of drive
current through the load in the
OFF state.

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CAUTION: If Output Open Load Detection is enabled, up to 50uA of current
will be pulled through the load with the output in the OFF state. Do not
enable open-load detection if you are driving loads that cannot tolerate 50uA
of “leakage” current in the OFF state, or if you do not want inputs pulled to
the ON state.
V
ON
8V MIN
OFF
EXT
EXC
8 to 28V
RTN
I/O
1N4006
EXC
NOTEPROTECTIONDIODEREQUIREDWITHINDUCTIVELOADS.
OPEN-DRAIN OUTPUTSSHARERETURN.
RELAY COIL/SOLENOIDDRIVER
EXCITATION ISREQUIRED. EXTERNALEXCITATION IS8VTO31VMAX.
Digital Counter Alarm Outputs (989EN-4016 Only):
Each of the eight counter channels on the 989EN-4016 has a corresponding
Alarm Output (8 Channels). These counters can be set to toggle the output
state upon alarm. They can be programmed to be reset either by the next
event count (momentary alarm), or by a manual reset (latching alarm).
Operation of the Alarm output is the same as standard Digital Outputs.
Note: Excitation is required for Alarm Outputs to operate.
ON
R
RTN
EXC EXT
EXC
OFF
VI/O
8-28V
LED
EXCITATIONIS REQUIRED. EXTERNALEXCITATIONIS 8V MINTO28V.
OPEN-DRAINOUTPUTS SHARE RETURN.
ALARMOUTPUT LED DRIVER CONNECTIONS
CONNECTIONS
Digital Outputs
Relay Coil or Solenoid Driver
(Note Protection –External
“Snubbing” Diode at Coil)
Digital Counter Output Alarms
Alarm outputs are the open-
drains of mosfet switches and
are intended for DC current-
sinking applications only.
Alarm Output LED Driver
Alarm Outputs have the same
characteristics as all the other
Digital Outputs.
Note: Alarm Outputs must be
enabled in order to operate.

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EXT
EXC
8to28V
EXC
ON
RTN
I/O
OFF
V
5.5V MIN
EXCITATIONISREQUIRED. EXTERNALEXCITATIONIS8VMINTO31VMAX.
OPEN-DRAINOUTPUTSSHARERETURN.
AVOID ENABLINGFASTSHORTFAULT PROTECTIONWITH INCANDESCENTLAMPSTO
AVOID NUISANCETRIPSWITHRESULTANTHIGH INRUSH CURRENTS.
INCANDESCENTLAMP CONTROL
Other Considerations For Output Control
•Built-in protection in the outputs will automatically shut-down specific
output operation for current-limit, thermal overload, excitation over-
voltage, and output drain over-voltage conditions. The outputs can
optionally be programmed to automatically retry their control, or
remain OFF following a thermal or over-voltage shut-down (default
response).
•If you enable open-load detection, a 50uA pull-down current will be
present with the output in the OFF state. This opposes the input
wetting current pull-up, so inputs must be tri-stated for this to work.
You may wish to reconsider enabling this detection if you happen to
be driving loads sensitive to small currents, or you cannot tolerate
unused inputs being pulled to the ON state.
You can select a faster responding 100-450us shutdown mechanism that is
triggered based on output Vds measurement (default), as opposed to a
thermal shutdown which allows the output to heat-up. Normally if an output
drives a shorted load, built-in thermal protection will kick-in to protect the
output. This effectively allows output port protection to be tailored to
incandescent lamp loads (thermal), or inductive loads (faster). However, the
fast shutdown may not trigger the thermal fault flag, as it acts too fast to
capture. But fast action does limit repeated thermal stresses which helps
preserve the life of the output driver.
CONNECTIONS
Digital Outputs
Incandescent Lamp Control
To drive lamps, you may avoid
using the fast short-fault
protection mode as it might
cause nuisance shut-downs as
a result of high ON inrush
currents.
Although selecting fast
shutdown helps limit repeated
thermal stress on the output
driver, it acts too fast to report
it via the output fault flags.

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This module supports Modbus over TCP/IP. You may use your own
software to issue Modbus commands to this module (see Modbus
Registers), or you may use a standard web browser, as these modules have
built-in web pages that allow you to setup and control the module. Simply
execute your web browser, type the IP address assigned to your module in
the “Address” window (http://128.1.1.100/ for our example), click [Go], and
you will be presented with a Home Page window similar to that shown below:
The Home Page provides buttons to access the other web pages of this
module that are used to configure the network parameters, change the user
name and password, and operate the module. For each new browser
session that accesses the Home Page of this module, you will be presented
with a window prompting you to enter the current User Name and Password
as shown on the following page. This information is required before the
program will allow you to make any other selections. The default user
name and password is “User” and “password” respectively.After
entering these defaults, you may wish to invoke the Password Configuration
Page to change these parameters to something more meaningful for you.
Note: If you cannot download the module web page, it may be that the
address of your network interface adapter is not set to a valid IP address
within the module’s default address domain. Refer to Applications Note
8500-734 for information on how to accomplish this.
WEB BROWSER
Home Page

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IMPORTANT: If you forget
your user name and password,
you can always toggle the
module into default mode via
the default mode push-button
at the front of the module, and
the password and username
will revert to the original
defaults noted on the previous
page (unit assumes IP
address 128.1.1.100), thus
allowing you to re-invoke the
Password Configuration Page
and change the username and
password as required.
Use up to 20 alphanumeric characters (case sensitive) to specify your
username, and 10 alphanumeric characters (case sensitive) to specify a
password. You will have to type in these entries twice to help prevent errors.
Click the submit button to write your changes to the module.
After completing your username/password changes, click on the appropriate
button at the bottom of the page to select another web page. If you made
changes, you may be prompted to re-enter your new username and
password before being permitted to move to other pages.
WEB BROWSER
Home Page
Password
Configuration Page

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After setting your username and password, you can click the “Network
Configuration Page” button and a screen similar to that shown below will
appear. Use this screen to set the network configuration parameters for
your module. You may have to consult your network administrator to
complete the contents of this page.
An IP Address is a unique identification number for any host (this module)
on any TCP/IP network (including the internet). The IP address is made up
of four octets (8 bits), each octet having a value between 0-255 (00H-FFH).
It is expressed here in decimal form, with a period placed between octets.
A Static IP Address is as the name implies—static, and represents a unique
fixed IP Address that is generally assigned by your service provider or
system administrator. The Default Mode static IP address assigned to this
module is 128.1.1.100 (refer to product side label).
NOTE: In order to network your PC with an Acromag module, you may have
to consult with your network administrator and either temporarily change
your TCP/IP configuration (see TCP/IP Properties of Network Configuration
in Windows), or create a separate private network using a second network
adapter installed in your PC (recommended). The necessary steps will vary
with your operating system. Refer to Acromag Application Note 8500-734 or
document 8500-815 to help accomplish this (located on the CDROM
shipped with your module or via download from our web site at
www.acromag.com).
The Number of Modbus Sockets refers to the number (1-5) of Modbus
TCP/IP access points to allow for this host. The default allows up to 5
sockets, but you can restrict access by reducing this number
WEB BROWSER
Network Configuration
Note that Acromag Series
9xxEN Ethernet I/O modules
may take from 3 to 30 seconds
to boot upon power-up,
depending on your network
configuration and whether a
DHCP server is present.
This module can be placed
into a default communication
mode via the DFT push-button
at the front of the module. To
activate, hold the DFT button
for 5 seconds. The Status
LED will start a slow blinking to
indicate default mode.
Default Mode uses a static IP
address of “128.1.1.100”, a
default subnet mask of
“255.255.255.0”, a default
username “User”, and a
default password “password”.

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The Modbus Port Number is set to port 502 by default, which has been
reserved for Modbus applications. Port numbers represents an endpoint or
“channel” for network communications. In this way, every IP address is
divided into many ports, and when one computer sends data to another
computer, it sends the data from a port of an IP address to a port on another
IP address. Any one port can only be used by one program at a time. The
use of port numbers allows different applications on the same computer to
utilize network resources without interfering with one another. The port
number could range from 0-99999, but most popular applications will use
port numbers at the low end of this range already set aside for specific
applications (such as 502 for Modbus, or 80 for HTTP). For example, ports
make it possible for you to check your email and browse the web at the
same time, because web browsers use port 80, while retrieving your email
uses port 110.
A Subnet Mask is used to subdivide the host portion of the IP address into
two or more subnets. The subnet mask will flag the bits of the IP address
that belong to the network address, and the remaining bits correspond to the
host portion of the address. The unique subnet to which an IP address
refers to is recovered by performing a bitwise AND operation between the IP
address and the mask itself, with the result being the sub-network address.
Gateway refers to the IP Address of the gateway, if your local area network
happens to be isolated by a gateway. Typically, it is assigned the first host
address in the subnet. If a gateway is not present, then this field should
contain an unused address within the host subnet address range.
The Active IP Address refers to the current IP Address being used by this
host, as opposed to any new assignments being made via this page.
The MAC Address refers to the Media Access Control Address that
uniquely identifies the hardware of this device. This is a unique fixed
address assigned to this module at the factory. In IEEE 802 networks, the
Data Link Control (DLC) layer of the OSI Reference Model is divided into two
sublayers: the Logical Link Control (LLC) layer, and the Media Access
Control (MAC) layer. The MAC layer interfaces directly with the network
media (each different type of network media requires a different MAC layer).
By default, the module is setup to use Static IP Addressing and a Static IP
Address of 128.1.1.100. You can optionally choose to have the IP address
assigned dynamically via DHCP, or DHCP w/Fallbacks. This will also
require that you specify a valid Host Name. Note that DHCP w/Fallback will
revert to the static IP address if your DHCP server cannot be found at the
address specified.
DHCP (Dynamic Host Configuration Protocol) refers to a protocol for
assigning dynamic IP addresses to devices on a network. With dynamic
addressing, a device can have a different IP address every time it connects
to the network. In some systems, it can even change while it is still
connected. DHCP also supports a combination of static and dynamic IP
addresses. For example, DHCP with fallback will revert to a static IP
address if the DHCP server cannot be found.
WEB BROWSER
Network Configuration
The Default Communication
Mode uses a static IP address
of “128.1.1.100”, a default
subnet mask of
“255.255.255.0”, a default
username of “User”, and a
default password of
“password”.

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18
The unit includes a default address push-button to cause the module to
assume a fixed default static IP address (128.1.1.100). This button is at the
front of the module and is used to toggle the module into, or out of Default
Mode. If you use the push-button at the front of the module to place the
module in default mode, then “Default Communications Mode” will be
indicated at the bottom of this screen.
Click the Submit button to complete any changes made on this page.
Click the Wink On/Off button to toggle the module in/out of “wink” ID mode.
In this mode, the module’s green RUN LED will blink to confirm identification.
Refer to the Technical Reference section of this manual to learn more about
IP Addressing terms and concepts.
Note: The 989EN is equipped with one I/O Port of 16 channels and
configuration is done on a port-wide basis.
WEB BROWSER
Network Configuration
I/O Configuration Page
After completing the
username/password
assignment, plus the network
configuration parameters, you
can use the I/O configuration
page to setup your I/O.
You can select from various
modes of operation for the
input and output channels of
each port. Once you have
carefully made your selections,
click the “Write Configuration”
button at the bottom of the
page to activate your
configuration (reconfiguration
takes effect immediately
following “Write
Configuration”).
I/O Configuration Page
Help
By clicking on the link at the
bottom of the I/O Configuration
Page, a quick reference help
page will appear. This is
useful for obtaining a
description of available
options.
To go back to the I/O
Configuration Page, scroll to
the bottom of the Help Page,
and there will be a link back.
Alternatively, you can click on
the back button on your
internet browser.

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I/O Configuration Page: Help –At the bottom of the I/O Configuration Page
is a help page to provide readily available answers to questions about the
controls. Each control is described in detail as on the next page, but also
obtainable via your internet browser.
Refer to the following definitions and the Modbus Memory Map for
information on optional modes of operation:
Input Functions
Input Wetting Current 2mA/16mA –Wetting current is used by the inputs
to sense switch contact closure and will attempt to seek a return path.
These currents also act like pull-ups for the tandem open-drain outputs,
which enables the I/O to be tested without actually wiring to the I/O
terminals. If this control is set to 2mA, the wetting current will be 2mA
continuously. If this control is set to 16mA(default), then the wetting current
is initially set to 16mA as the input crosses the threshold, and folds back to
2mA continuous, 20ms after crossing the ON threshold. The purpose of the
higher initial current is to help prevent oxide build-up on external switch
contacts.
Metallic switch contacts can develop higher contact resistance over time due
to corrosion induced by humidity, salt, and other elements that exist in harsh
environments. Use of the 16mA setting provides higher initial wetting current
during contact transfer to reduce or eliminate potential oxide build-up.
However, elastomeric switch contacts are made of carbon material and have
a high contact resistance, with common resistance up to 1KΩ. With these
types of contacts, the pull-up/wetting current must be reduced to prevent
excessive power dissipation in the contact. High currents through these
switches can produce an IR voltage that can cause the input signal to rise
back above the 4.0V threshold. Thus, you should select 2mA for those
applications where 16mA cannot be tolerated.
If Input Tri-State is ON, this field will have no effect, as the wetting current
generators are disabled in tri-state mode.
Input Tri-State OFF (Default)/ON –Inputs may be tri-stated and then act as
a high-impedance comparator input with a 4.0V threshold (3.7-4.3V range).
Wetting current generators are disabled with inputs tri-stated, or without
excitation connected. Note that tri-stated inputs will also leave the tandem
open-drain output floating if no load is connected. You may optionally utilize
the open-load detection pull-downs to pull these inputs to the ON state.
IMPORTANT: If inputs are tri-stated, excitation must be above 8V, or the
output drains will float unless loaded and/or pulled up externally. If the I/O is
not pulled up above the 4.0V input threshold, the output OFF state may not
register properly, or indicate ON.
Input Reset –Click this button to reset the inputs without invoking a power-
on, output, or system reset of the unit. You do not normally need to use this
control, but it may be useful for trouble-shooting and isolating I/O problems
between input & output circuitry.
WEB BROWSER
I/O Configuration Page
Help
I/O Configuration
The built-in wetting current
generators do not operate
without excitation, or with
inputs tri-stated.
Without a driver, load, or pull-
up connected to the I/O, the
tri-stated I/O is essentially
floating and may not register
the OFF state correctly. In this
state, you will have to use I/O
pull-ups to pull the OFF state
signal above 4.3V in order to
be able to read back the
correct I/O state.
Note that wetting currents are
reduced low excitation
voltages below 8V.
TIP: Unused tri-stated inputs
may utilize the built-in open-
load detection pull-downs to
pull to the ON state.
TIP: You can increase wetting
currents by paralleling inputs,
or connecting to an external
excitation supply and adding
an I/O pull-up to the excitation
voltage rail.