IRT Communications DMM-4880 User manual

DMM‐4880 & DMX‐4880 Instruction Book Revision 0
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IRT Eurocard
Type DMM‐4880 & DMX‐4880
4 STM‐1 to STM‐4
Multiplexer / De‐Multiplexer
Designed and manufactured in Australia
IRT can be found on the Internet at:
http://www.irtelectronics.com
I R T Electronics Pty Ltd A.B.N. 35 000 832 575
26 Hotham Parade, ARTARMON N.S.W. 2064 AUSTRALIA
National: Phone: [phone] Fax: [phone]
International: [phone] [phone]
Email: [e-mail]
Web: www.irtelectronics.com
DANGER
A
void direct exposure to beam
Peak power 2 mW
Wavelength 1270–1610nm
Class 1 LASER Product
Invisible LASER radiation-
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IRT Eurocard
Type DMM‐4880 & DMX‐4880
4 STM‐1 to STM‐4
Multiplexer / De‐Multiplexer
Revision History
Revision Date By Change Description Applicable to:
0 13/08/2010 AL Original Issue. Firmware versions ≥
DMM4880 F3V1 S3V1 &
DMX4880 F3V1 S3V1
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IRT Eurocard
Type DMM‐4880 & DMX‐4880
4 STM‐1 to STM‐4
Multiplexer / De‐Multiplexer
Instruction Book
Table of Contents
Section Page
Revision History 2
Operational Safety 4
General Description 5
Technical Specifications 6
Configuration 7
Installation 8
Signal Connections 8
DMM‐4880 8
DMX‐4880 10
Front Panel LEDs 11
DMM‐4880 11
DMX‐4880 11
Front and rear layouts 12
Operation 13
SNMP – What Is It? 13
DMM‐4880 & DMX‐4880 SNMP Functions 15
Maintenance & Storage 16
Warranty & Service 16
Equipment return 16
This instruction book applies to firmware versions ≥DMM4880 F3V1 S3V1 and DMX4880 F3V1 SV1.
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Operational Safety:
WARNING
Operation of electronic equipment involves the use of voltages and currents that
may be dangerous to human life. Note that under certain conditions dangerous
potentials may exist in some circuits when power controls are in the OFF position.
Maintenance personnel should observe all safety regulations.
Do not make any adjustments inside equipment with power ON unless proper
precautions are observed. All internal adjustments should only be made by suitably
qualified personnel. All operational adjustments are available externally without
the need for removing covers or use of extender cards.
Optical Safety
The light emitted from the LASER diode used in this system is
invisible and may be harmful to the human eye. Avoid looking
directly into the fibre optic cable or connectors or into the
collimated beam along their axis when the device is in operation.
Operating the LASER diode outside of its maximum ratings may
cause device failure or a safety hazard.
DANGER
A
void direct exposure to beam
Peak power 2 mW
Wavelength 1270–1610nm
Class 1 LASER Product
Invisible LASER radiation-
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IRT Eurocard
Type DMM‐4880 & DMX‐4880
4 STM‐1 to STM‐4
Multiplexer / De‐Multiplexer
General Description
The DMM‐4880 and DMX‐4880 are part of a family of network adapters for converting between STM‐1 and STM‐4
formats.
With the DMM‐4880 up to four 155Mb/s STM‐1 electrical signals can be multiplexed together and converted into
a single 622Mb/s STM‐4 optical NRZ signal.
Inputs are automatically equalised for lengths of up to 200m of Belden 8281 or equivalent cable.
Front panel indications on the DMM‐4880 multiplexer shows if valid STM‐1 signals are present.
Optional STM‐4 reference input for synchronizing to STM‐4 network, if required.
The DMX‐4880 separates the 622Mb/s STM‐4 signal back into the original four 155Mb/s STM‐1 signals.
Front panel indications on the DMX‐4880 de‐multiplexer shows if valid encoded STM‐1 signals are present.
SNMP (Simple Network Management Protocol) is available for monitoring and control when used in an IRT frame
fitted with SNMP capability.
The DMM‐4880 and DMX‐4880 are designed to fit IRT’s standard Eurocard frames and may be used alongside any
other of IRT’s analogue or digital Eurocards.
Standard features:
•Up to 4 STM‐1 electrical streams on one STM‐4 link
•Automatic Input equalisation > 200m
•Recovers transmitted STM‐1 signals with minimal user setup
•Monitoring and control via SNMP
•Eurocard format
DMM-4880 & DMX-4880 Block Diagram
DMM-4880 DMX-4880
A
larm O/P
SNMP
A
larm O/P
SNMP
NOTE: * STM-4 Reference input optional.
STM-1 (1) I/P 1
STM-1 (2) I/P 2
STM-1 (3) I/P 3
STM-1 (4) I/P 4
STM-4 Ref
*
Ref I/P
STM-4
Network
O/P I/P
O/P 1 STM-1 (1)
O/P 2 STM-1 (2)
O/P 3 STM-1 (3)
O/P 4 STM-1 (4)
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Technical Specifications
DMM‐4880:
Inputs:
Type 1 4 x STM‐1 (OC‐3), 75Ω, 1Vp‐p, BNC connector.
Electrical Characteristics CMI encoded.
Data Rate 155.52 Mb/s.
Equalisation Automatic, > 200m at 155Mb/s for Belden 8281 or equivalent cable.
Type 2 (Optional) 1 x optical STM‐4 (OC‐12), LC/PC (standard) optical connector.
Optical Characteristics NRZ encoded.
Data Rate 622.08 Mb/s.
Output:
Type 1 x optical STM‐4 (OC‐12), SC/PC (standard) optical connector1.
Optical Characteristics NRZ encoded.
Data Rate 622.08 Mb/s.
Alarm Output: MAJOR Not used. Open circuit on loss of power.
MINOR Open circuit on no valid input STM‐1 streams present, or loss of power.
DMX‐4880:
Input:
Type 1 x STM‐4 (OC‐12), optical, SC/PC optical connector (standard).
Optical Characteristics NRZ encoded.
Data Rate 622.08 Mb/s.
Outputs:
Type 4 x STM‐1 (OC‐3) 75Ω, 1Vp‐p, BNC connector.
Data Rate 155.52 Mb/s.
Alarm Output: MAJOR Open circuit on no valid STM‐4 input present, or loss of power.
MINOR Open circuit on no valid output STM‐1 streams present, or loss of power.
Optical
Optical path loss23 to 18 dB with PIN detector (typically 20dB),
Optical fibre Designed for use with 9/125 μm single mode fibre.
Optical wavelength 1310nm (DFB laser ‐standard).
Optical connectors SC/PC (standard).
DMM‐4880 optical output 0 dBm +3/‐0 dB standard DFB laser,
DMX‐4880 optical input PIN detector, ‐3 to ‐18 dBm input level
Power Requirements 28 Vac CT (14‐0‐14) or ±16 Vdc.
Power consumption 7 VA.
Other
Temperature range 0 ‐50° C ambient.
Mechanical Suitable for mounting in IRT 19" rack chassis with input, output and power
connections on the rear panel.
Finish Front panel Grey background, black lettering & red IRT logo.
Rear assembly Detachable silk‐screened PCB with direct mount connectors to Eurocard and
external signals.
Dimensions 6 HP x 3 U x 220 mm IRT Eurocard.
NOTE: 1 If optional STM‐4 reference fitted, standard output optical connector is an
LC/PC type.
2Optical attenuator required for optical paths <3dB optical loss.
Due to our policy of continuing development, these specifications are subject to change without notice.
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Configuration
Other than the following DIP switch settings, there are no user configurable settings.
DMM‐4880:
SW1‐1 Not used.
SW1‐2 Not used.
SW1‐3 Not used.
SW1‐4 Not used.
SW1‐5 Not used.
SW1‐6 Not used.
SW1‐7 Not used.
SW1‐8 OFF Enable major and minor SNMP alarms to the frame Agent (CDM card)3.
ON Disable major and minor SNMP alarms to the frame Agent (CDM card)3.
NOTE: 3 When using TRAPS via SNMP, depending on how system is set up, in order to avoid double reporting
of alarms via the DMM‐4880 card and the CDM card (SNMP Agent) of the frame, major and minor
SNMP alarms that are reported to the CDM card of the frame can be disabled.
DMX‐4880:
SW1‐1 Not used.
SW1‐2 Not used.
SW1‐3 Not used.
SW1‐4 Not used.
SW1‐5 Not used.
SW1‐6 Not used.
SW1‐7 Not used.
SW1‐8 OFF Enable major and minor SNMP alarms to the frame Agent (CDM card)4.
ON Disable major and minor SNMP alarms to the frame Agent (CDM card)4.
NOTE: 4 When using TRAPS via SNMP, depending on how system is set up, in order to avoid double reporting
of alarms via the DMX‐4880 card and the CDM card (SNMP Agent) of the frame, major and minor
SNMP alarms that are reported to the CDM card of the frame can be disabled.
12345678
ON DIP
SW1
12345678
ON DIP
SW1
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Installation
Pre‐installation:
Handling:
This equipment may contain or be connected to static sensitive devices and proper static free handling
precautions should be observed.
Where individual circuit cards are stored, they should be placed in antistatic bags. Proper antistatic procedures
should be followed when inserting or removing cards from these bags.
Power:
AC mains supply: Ensure that operating voltage of unit and local supply voltage match and that correct rating
fuse is installed for local supply.
DC supply: Ensure that the correct polarity is observed and that DC supply voltage is maintained within
the operating range specified.
Earthing:
The earth path is dependent on the type of frame selected. In every case particular care should be taken to ensure
that the frame is connected to earth for safety reasons. See frame manual for details.
Signal earth: For safety reasons a connection is made between signal earth and chassis earth. No attempt should
be made to break this connection.
Installation in frame or chassis:
See details in separate manual for selected frame type.
Signal Connections:
DMM‐4880:
STM‐1 Inputs:
STM‐1 inputs are by BNC connectors each terminated in 75Ω. Input cable equalisation is automatic for up to 200m
of high quality 75Ωcoaxial cable (Belden 8281 or equivalent). No adjustments are required.
STM‐4 Reference Input:
The STM‐4 reference input is an option that is fitted at time of ordering. The connector type is an LC/PC (standard)
optical connector that sits next to the STM‐4 output, which will be the same connector type. If the STM‐4
reference input option is not fitted the STM‐4 output connector is an SC/PC (standard) type.
The standard optical detector used is a PIN detector and is rated for an optical input between ‐3dBm and ‐18dBm.
If the input signal strength is greater than ‐3dBm an optical attenuator (5 or 10 dB recommended) must be used to
avoid overdriving the detector.
STM‐4 Output:
One STM‐4 NRZ encoded output is provided by an SC/PC (standard) optical connector. Should the optional STM‐4
reference input be fitted the connector type will be an LC/PC (standard) type to match that of the STM‐4 reference
input.
Alarm Outputs:
Two relay alarm output states are provided via a phoenix style 3‐pin plug. Pin 3 is designated as Major, pin 2 is
designated as Minor, and pin 1 is ground. Both alarms are referenced to ground.
Alarm conditions are as follows:
Major Not used;
Minor Switch to Open Circuit on no valid input STM‐1 streams present.
Both Major and Minor alarms switch to Open Circuit on power failure.
1 GND
2 MINOR
3 MAJOR
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STM-1 I/P3
ALARM O/P
STM-1 I/P2
DMM-4880
Rear Assembly Connections
(Standard)
STM-4 O/P
SK 7 IN4
PL4
SK10
SK 2 IN3
PL3
SK 11 IN2
SK 6 IN1
1
2
3
1-GND
2-MINOR
3–MAJOR
STM-1 I/P4
STM-1 I/P1
STM-1 I/P3
ALARM O/P
STM-1 I/P2
DMM-4880
Rear Assembly Connections
(With STM-4 Ref. I/P option)
STM-4 O/P
SK 7 IN4
PL4
SK10
SK 2 IN3
PL3
SK 11 IN2
SK 6 IN1
1
2
3
1-GND
2-MINOR
3–MAJOR
STM-1 I/P4
STM-1 I/P1
STM-4 Ref I/P
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DMX‐4880:
STM‐4 Input:
The optical STM‐4 input port on the rear of the unit is an SC/PC (standard) optical connector for use with single
mode fibre.
The standard optical detector used is a PIN detector and is rated for an optical input between ‐3dBm and ‐18dBm.
If the input signal strength is greater than ‐3dBm an optical attenuator (5 or 10 dB recommended) must be used to
avoid overdriving the detector.
STM‐1 Outputs:
Four STM‐1 electrical outputs are provided as 75Ωoutput BNC connectors. Each STM‐1 output is equivalent to the
corresponding STM‐1 electrical input on the matching DMM‐4880.
Alarm Outputs:
Two relay alarm output states are provided via a phoenix style 3‐pin plug. Pin 3 is designated as Major, pin 2 is
designated as Minor, and pin 1 is ground. Both alarms are referenced to ground.
Alarm conditions are as follows:
Major switch to Open Circuit on no valid STM‐4 input present;
Minor switch to Open Circuit on no valid output STM‐1 streams present, or
no valid STM‐4 input present.
Both Major and Minor alarms switch to Open Circuit on power failure.
1 GND
2 MINOR
3 MAJOR
STM-1 O/P 3
ALARM O/P
DMX-4880
Rear Assembly Connections
STM-4 I/P
STM-1 O/P 2
SK 9 OUT3
PL4
SK10
SK 4 OUT4
SK 8 OUT1
SK3 OUT2
PL3
1
2
3
1-GND
2-MINOR
3–MAJOR
STM-1 O/P 1
STM-1 O/P 4
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Front Panel LEDs:
DMM‐4880:
I/P 1, I/P 2, I/P 3 and I/P 4 LEDs correspond to STM‐1 inputs 1, 2, 3 and 4 respectively. When a valid STM‐1 input is
present corresponding LED will illuminate green.
The REF I/P LED illuminates green when there is a valid STM‐4 input signal being used as a reference for the STM‐4
output signal to synchronize with. Only valid for DMM‐4880 fitted with optional STM‐4 reference input port.
The ALARM LED does not illuminate as there is no Major Alarm associated with the DMM‐4880.
DMX‐4880:
O/P 1, O/P 2, O/P 3 and O/P 4 LEDs correspond to STM‐1 outputs 1, 2, 3 and 4 respectively. When a valid STM‐1
signal is present within the incoming STM‐4 signal corresponding LED will illuminate green.
The ALARM LED illuminates RED when there is no valid STM‐4 input present.
I/P 2
I/P 1
I/P 4I/P 3
REF I/P
ALARM
O/P 2
O/P 1
O/P 4O/P 3
ALARM
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Front & rear panel connector diagrams
The following front panel and rear assembly drawings are not to scale and are intended to show connection order
and approximate layout only.
I/ P 1 I/ P 2
I/P 4I/ P 3
ALARM
REF I/P
DC
DMM-4880
N140
O/P 1 O/P 2
O/P 4O/P 3
ALARM
DC
DMX-4880
N140
SK 9 OUT3
PL4
SK10
SK 4 OUT4
SK 8 OUT1
SK3 OUT2
PL3
1
2
3
1-GND
2-MINOR
3–MAJOR
SK 7 IN4
PL4
SK10
SK 2 IN3
PL3
SK 11 IN2
SK 6 IN1
1
2
3
1-GND
2-MINOR
3–MAJOR
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SNMP
What Is It?
SNMP stands for Simple Network Management Protocol. It is an application layer protocol for managing IP
(Internet Protocol) based systems. SNMP enables system administrators to manage system performance, and to
find and solve system problems. SNMP runs over UDP (User Datagram Protocol), which in turn runs over IP.
Three types of SNMP exist: SNMP version 1 (SNMPv1), SNMP version 2 (SNMPv2) and SNMP version 3 (SNMPv3).
It is not the intention here to discuss the differences between various versions, only to bring attention to the fact
that IRT Electronics modules, fitted with SNMP capability, use SNMPv1.
An SNMP managed network consists of three key components: Network Management Systems (NMS), agents, and
managed devices.
An NMS is the console through which the network administrator performs network management functions, such
as monitoring status (e.g. alarm states) and remote controlling, of a set of managed devices. One or more NMSs
must exist on any managed network. Generally the NMS is a computer running third party SNMP control software.
There are a number of third party SNMP software applications currently available on the market.
An NMS polls, or communicates with, an agent. An agent is a network management software module that resides
in a managed device. An agent has local knowledge of management information and translates that information
into a form compatible with SNMP. The agent, therefore, acts as an interface between the NMS and the managed
devices. The NMS sends a request message, and control commands for the managed devices, to the agent, which
in turn sends a response message, containing information about the managed devices, back to the NMS.
A managed device contains an SNMP agent and resides on a managed network. Managed devices collect and store
management information and make this information available to NMSs using SNMP.
Managed device agent variables are organised in a tree structure known as a Management Information Base
(MIB). Within the MIB are parameters pertaining to the managed device. An Object Identifier (OID) number within
the MIB defines the managed device type. This is a unique number specific to the model of managed device. Other
information relating to the device is also stored, information such as alarm states, controllable settings, etc. The
MIB tree is organised in such a way that there will be no two MIB files with conflicting placements.
Normally an NMS polls an agent for information relating to the MIB in a managed device to be sent back to the
NMS. When certain conditions are met within the MIB, such as major alarm conditions, for example, the agent
automatically sends what is known as a trap to the NMS without any prompting from the NMS. This allows
automatic notification of a predetermined event.
NMS
NMS
IP
Network
MIB
SNMP Agent
Protocol Engine SNMP Agent
MIB
SNMP Agent
Protocol Engine SNMP Agent
MIB
SNMP Agent
Protocol Engine SNMP Agent
SNMP Block Diagram
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SNMP with IRT Products:
IRT Electronics currently employs SNMPv1 with its SNMP capable frames. The frame acts as an agent when fitted
with a CDM‐xxxx module. This module has its own designated slot next to the power supply so as to not affect the
number of modules that the frame will take. Communication between the NMS, the frame and its loaded modules
are via this CDM‐xxxx module. Note that the NMS software is third party and not supplied by IRT Electronics.
Ethernet connection for SNMP operation is via an RJ45 connector on the rear of the frame, below the mains inlet.
Ethernet rate runs at either 10 baseT or 100 baseT.
Frame parameters, such as Name, Address and Location, are set via an RS232 interface, a D9 connector on the
rear of the frame below the mains inlet. A software terminal emulator, such as Tera Term or HyperTerminal, is
used for setting and reading the parameters of the frame.
IRT modules that are SNMP compatible need a plug‐in SMU‐4000 module with a program relevant to the module
that it is plugged into. Depending on the module, besides the module identification, parameters such as alarm
states, inputs and controls etc. are communicated to the CDM‐xxxx agent via a data bus on the rear of the frame.
Thus the CDM‐xxxx collects information on what is loaded within the frame, what positions they occupy, and their
current status for communication to the NMS when the NMS sends a request for information.
In the event of a major alarm from any of the SNMP compatible modules, or power supplies, a trap is
automatically sent by the CDM‐xxxx agent to the NMS without any prompting by the NMS. This alerts the operator
to any fault conditions that may exist that need immediate attention.
FRU-4000
FRAME
110/240 V 50/60 Hz
0.7 A (max.)
FUSES
110/120 Vac
1A S.B.
220/240 Vac
500 mA S.B.
AS3260 approval no.: CS6346N
Ass. no.: 804692
+-
48Vdc
Alarm
RS232
Ethernet
IRT SNMP Connections
IRT modules fitted
with SMU-4000 PSU’s
CDM-xxxx
IRT SNMP Frame
IRT SNMP Frame
IRT modules fitted
with SMU-4000 PSU’s
CDM-xxxx
IP
Network Ethernet Cable
Ethernet Cable
Ethernet Cable
NMS
IRT SNMP Setu
p
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DMM‐4880 & DMX‐4880 SNMP Functions:
With the DMM‐4880/DMX‐4880 installed in an IRT frame with SNMP capability, the following SNMP functions are
capable of being monitored and controlled by a Network Management System (NMS).
DMM‐4880:
An indication of the current state of the Urgent and Non Urgent alarms
[noAlarms (1)],
[UrgentAlarms (2) – Not applicable],
[nonUrgentAlarms (3) – no valid STM‐1 input on any channel];
Information about each channel:
Channel number,
An indication that the channel input signal is present5[notPresent (1), present (2)],
A 15 byte maximum Alias (name) for the channel can be read and set;
Trap automatically sent, if enabled, upon loss or restoration of an input signal
[notEnabled (1), enabled (2)];
The firmware version of the main FPGA in the format ‘x.y’, where x is the major rev. no. and y the minor:
The software version of the processor in the format ‘x.y’, where x is the major rev. no. and y the minor:
Unit reset control ‐resets system up time counter. A set with a value of 2 sent to this OID will cause a
system reset to occur. When queried returns a Null (0).
NOTE: 5 When an STM‐1 input is not present on a channel of the DMM‐4880 the resultant STM‐4 signal
contains an AIS (Alarm Indication Signal) in the channel’s allocated space. AIS is defined as being all 1’s
within the stream.
DMX‐48800:
An indication of the current state of the Urgent and Non Urgent alarms
[noAlarms (1)],
[UrgentAlarms (2) – no, or invalid, STM‐4 input signal present],
[nonUrgentAlarms (3) – no valid STM‐1 signals encoded on any channel. All STM‐1 signals are AIS];
An indication of the signal status of the STM‐4 input {notpresent (1), present (2)];
Information about each channel:
Channel number,
An indication that the channel input signal is present6[AIS (1), present (2)],
A 15 byte maximum Alias (name) for the channel can be read and set;
An indication that either all encoded STM‐1 signals are AIS, or at least one is an active STM‐1
[normal (1) – at least one STM‐1 signal is active, allInputAIS (2) – all STM‐1 signals are AIS7]
Trap automatically sent, if enabled, upon loss or restoration of the STM‐4 input signal
[notEnabled (1), enabled (2)];
Trap automatically sent, if enabled, upon detection or not detection of all AIS STM‐1 input signals
[notEnabled (1), enabled (2)];
The firmware version of the main FPGA in the format ‘x.y’, where x is the major rev. no. and y the minor:
The software version of the processor in the format ‘x.y’, where x is the major rev. no. and y the minor:
Unit reset control ‐resets system up time counter. A set with a value of 2 sent to this OID will cause a
system reset to occur. When queried returns a Null (0).
NOTE: 6 When an STM‐1 input is not present on a channel of the DMM‐4880 the resultant STM‐4 signal
contains an AIS (Alarm Indication Signal) in the channel’s allocated space. AIS is defined as being all 1’s
within the stream. The resultant channel’s STM‐1 output will be an AIS.
7 No STM‐1 signals present on all DMM‐4880 inputs,
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Maintenance & Storage
Maintenance:
No regular maintenance is required.
Care however should be taken to ensure that all connectors are kept clean and free from contamination of any
kind. This is especially important in fibre optic equipment where cleanliness of optical connections is critical to
performance.
Storage:
If the equipment is not to be used for an extended period, it is recommended the whole unit be placed in a sealed
plastic bag to prevent dust contamination. In areas of high humidity a suitably sized bag of silica gel should be
included to deter corrosion.
Where individual circuit cards are stored, they should be placed in antistatic bags. Proper antistatic procedures
should be followed when inserting or removing cards from these bags.
Warranty & Service
Equipment is covered by a limited warranty period of three years from date of first delivery unless contrary
conditions apply under a particular contract of supply. For situations when “No Fault Found” for repairs, a
minimum charge of 1 hour’s labour, at IRT’s current labour charge rate, will apply, whether the equipment is
within the warranty period or not.
Equipment warranty is limited to faults attributable to defects in original design or manufacture. Warranty on
components shall be extended by IRT only to the extent obtainable from the component supplier.
Equipment return:
Before arranging service, ensure that the fault is in the unit to be serviced and not in associated equipment. If
possible, confirm this by substitution.
Before returning equipment contact should be made with IRT or your local agent to determine whether the
equipment can be serviced in the field or should be returned for repair.
The equipment should be properly packed for return observing antistatic procedures.
The following information should accompany the unit to be returned:
1. A fault report should be included indicating the nature of the fault
2. The operating conditions under which the fault initially occurred.
3. Any additional information, which may be of assistance in fault location and remedy.
4. A contact name and telephone and fax numbers.
5. Details of payment method for items not covered by warranty.
6. Full return address.
7. For situations when “No Fault Found” for repairs, a minimum charge of 1 hour’s labour will apply,
whether the equipment is within the warranty period or not. Contact IRT for current hourly rate.
Please note that all freight charges are the responsibility of the customer.
The equipment should be returned to the agent who originally supplied the equipment or, where this is not
possible, to IRT direct as follows.
Equipment Service
IRT Electronics Pty Ltd
26 Hotham Parade
ARTARMON
N.S.W.2064
AUSTRALIA
Phone: [phone] Fax: [phone]
Email: [email protected]
IRT Communications
www.irtcommunications.com