Albalá Ingenieros ASW3000C01 User manual

ASW3000C01
DVB-ASI AUTOMATIC CHANGE-OVER SWITCH WITH ADVANCED TS
FAILURE DETECTION FUNCTIONS
Version 1.0
Albalá Ingenieros, S.A.
Medea, 4 - 28037 Madrid - Spain
17 November 2014 - © Albalá Ingenieros S.A. - All rights reserved

ASW3000C01

ASW3000C01
DVB-ASI AUTOMATIC CHANGE-OVER SWITCH WITH ADVANCED TS FAILURE
DETECTION FUNCTIONS
Version 1.0
1. DESCRIPTION ...................................................................................................................... 5
1.1. The ASW3000C01 .......................................................................................................................... 5
1.2. Features ............................................................................................................................................. 7
1.3. Block diagram .................................................................................................................................. 8
2. SPECIFICATIONS ................................................................................................................. 9
3. INSTALLATION .................................................................................................................. 11
3.1. Initial inspection .......................................................................................................................... 11
3.2. Safety instructions ...................................................................................................................... 11
3.3. Environmental considerations ................................................................................................ 12
3.4. Power considerations ................................................................................................................. 12
3.5. Installing the module in the mounting frame ................................................................... 12
3.6. Interconnection ............................................................................................................................ 14
3.6.1. Electrical DVB-ASI video connections .......................................................................... 15
3.6.2. GPIO connections ................................................................................................................ 15
4. OPERATION ...................................................................................................................... 17
4.1. Front panel description .............................................................................................................. 17
4.2. Configuration from the front panel ...................................................................................... 18
4.3. Functional description ............................................................................................................... 18
4.3.1. The error conditions ........................................................................................................... 19
4.3.1.1. GPI input ........................................................................................................................ 19
4.3.1.2. Absence of input signal. ........................................................................................... 19
4.3.1.3. Loss of synchronization of the transport stream. ........................................... 19
4.3.1.4. Error in the sync byte of the packets ................................................................... 20
4.3.1.5. PAT errors ...................................................................................................................... 20
4.3.1.6. Continuity error in the PAT packets. .................................................................... 20
4.3.1.7. Useful load of the transport stream .................................................................... 21
4.3.1.8. A percentage of null packets above or below set thresholds ..................... 21
4.4. Operating modes ......................................................................................................................... 21
4.4.1. Automatic Mode operation ............................................................................................. 21
4.4.2. Semiautomatic Mode operation ................................................................................... 22
4.4.3. Manual Mode operation ................................................................................................... 22

4.4.4. Priority inversion: Automatic and Semiautomatic Modes ................................... 22
4.4.5. Output mode selection ..................................................................................................... 22
4.4.6. Signal at the output when errors are present at the inputs ................................ 23
4.4.7. Selection of DVB-T/no DVB-T mode ............................................................................. 23
4.5. Module remote control and supervision ............................................................................. 24
4.5.1. Details of the ASW3000C01 registers ......................................................................... 25
5. GLOSSARY ........................................................................................................................ 29
6. REGULATIONS .................................................................................................................. 31
7. VERSIONS ......................................................................................................................... 33

Albalá Ingenieros | Manual ASW3000C01
1. DESCRIPTION
1.1. The ASW3000C01
The ASW3000C01 automated switch is a selector for two sources of DVB-ASI signals
that operates based upon the presence of signals, specific parameters of those signals or
the activation of GPI signals.
The ASW3000C01 provides two signal inputs, Main and Reserve. The selected input is
distributed to four outputs, and one of those outputs is protected by a bypass relay,
there by guaranteeing continuity of the signal even if a power supply failure occurs or
the module is extracted from the mounting frame.
The criteria for switching are based upon the requirements of the transport stream as
per ETSI TR 101 290 V1.2.1(2001-05) as well as several extra criteria. Each failure
condition can be selected or not for consideration for switching. The conditions that can
be detected are:
- Absence of input signal.
- Loss of the transport stream (TS) packets.
- Errors in the packet headers.
-Absence of or errors in the PAT (Program Association Table) packets during a
programmable interval lasting from 40ms to 10 seconds.
- Usable load of the TS above or below user-established thresholds.
-A percentage of null packets (PID equal to 0x1FFF) above or below the
user-established thresholds.
- Activation of a GPI input to indicate that the signal is not valid.
-The ASW3000C01 module provides three operating modes to establish the manner
in which switching occurs between the inputs.
- Automatic: when no errors are present in the inputs, the input with higher
priority is always selected.
- Semiautomatic: switching from one input to the other only occurs if errors are
detected in one input but not in the other input. This mode minimizes signal
switching.
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Albalá Ingenieros | Manual ASW3000C01
- Manual: the user, via the front panel or remotely determines which input is
selected at any given moment.
The ASW3000C01 performs switching at the TS packet level. Furthermore, when the
signals are DVB-T type with a difference is delay that is less than four times the packet
period, the switching is seamless.
All switching between the signal sources is indicated by an LED and an audible beep that
can be masked.
Both the signal selected and any error conditions detected at either input are indicated
via open-collector GPOs and via the module's remote control.
It is possible to monitor the ASW3000C01 status remotely using a communications
controller module installed in the same mounting frame. In addition, certain controller
modules provide SNMP management and the ability to record events in a file including
date and time information for further analysis.
The ASW3000C01 is a TL3000 terminal line module and can be housed in a three rack
unit (3 RU) UR3000 mounting frame or a 1 RU UR3100 mounting frame.
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Albalá Ingenieros | Manual ASW3000C01
1.2. Features
• Automatic change-over switch for DVB-ASI signals.
• Two DVB-ASI inputs.
• Failure detection criteria as per ETSI TR 101 290 V1.2.1.
- Absence of input signal.
- Transport stream sync loss.
- Errors in transport stream packet header.
- PAT errors.
- Transport stream useful payload above or below established thresholds.
- Activation of external GPI input with configurable polarity.
• Supports transport streams with packets of 188 and 204 bytes.
• Distributes the selected input to four outputs.
•Provides a bypass relay on the rear board that enables the input signal to be passed
through to one of the outputs in case of power loss or module removal.
• Switching takes place at packet boundaries to reduce TS data disturbance.
•Seamless switching is available with DVB-T signals when delay between inputs is less
than four TS packets.
• Provides automatic cable equalizers at the inputs.
• Provides three switching modes: automatic, semiautomatic and manual.
• Front panel indication of input selected and operating mode.
• Front panel indication of failure in the main or reserve inputs.
• Acoustic and visual indicators warn against changes in the selected source.
•Module control and supervision can be done remotely when the mounting frame is
equipped with a communications controller module.
•One UR3000 mounting frame can house up to 12 ASW3000C01 modules. If power
supply redundancy is required and FA3000 or FA3001 modules are used then only 10
modules can be housed in the mounting frame. If PSU3300 or PSU3301 modules are
used for this purpose then up to 12 modules can be installed.
• One UR3100 mounting frame can house up to three ASW3000C01 modules.
• Low power.
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Albalá Ingenieros | Manual ASW3000C01
1.3. Block diagram
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Albalá Ingenieros | Manual ASW3000C01
2. SPECIFICATIONS
DVB-ASI signal input
Connector BNC
Impedance 75Ω ± 1 %
Return loss >17dB up to 270 MHz
Input return loss when bypass is active >17dB up to 270 MHz
Output protected with bypass relay Yes
Equalizable cable length:
Belden 8281 >100 m
DVB-ASI signal output
Connector BNC
Impedance 75Ω ± 1 %
Return loss >17dB up to 270 MHz
Output return loss when bypass is active >17dB up to 270 MHz
Input to output bypass insertion loss <0.1dB up to 270 MHz
Number of outputs 4
Amplitude 800mVpp ± 10 %
Rise and fall time (20 % - 80 %) 1 ns typ.
DVB-ASI signal
Signal format According to EN 50083-9 standard
GPI input
Connector Plug-in terminal,
3.81mm pitch
Type 100 kΩ pull-up to 5 V
Number of inputs 2
Activation Closing contact to ground
Allowed voltage range 0 .. 24 V
GPO output
Connector Plug-in terminal,
3.81mm pitch
Type Open/closed NPN transistor collector
Number of outputs 3
Allowed voltage range 0 .. 24V 50mA max.
General
Maximum power supply current + 270 / - 270 mA
Operating temperature range 0 .. 50 °C
Approximate weight 300 g
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Albalá Ingenieros | Manual ASW3000C01
ASW3000C01
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Albalá Ingenieros | Manual ASW3000C01
3. INSTALLATION
THE ASW3000C01 MODULE CONTAINS ELECTRONIC DEVICES SENSITIVE TO
ELECTROSTATIC DISCHARGE. Always use antistatic bags clearly identified
with a high degree of shielding for storage and transportation.
The ASW3000C01 module is composed of two parts: one ASW3000P01 main board and
one ASW3000P02 rear board. Both parts must be installed in a UR3000 or UR3100
mounting frame following the instructions in the corresponding section of this chapter.
3.1. Initial inspection
Verify that the package has been properly handled during transport. After opening the
packaging, check that one ASW3000P01 main board and one ASW3000P02 rear board
are inside.
You must notify your Albalá Ingenieros distributor or dealer of any damage or defects
observed.
Follow the instructions in this manual to install this module in the mounting frame.
3.2. Safety instructions
•This equipment must be connected to a mains outlet with a protective
earth connection. Never use extension cords that do not have protective
earthing connection. The lack of an effective electrical connection between
the ground pin in the mains input connector of the equipment and the
protective earth of the electrical power distribution can cause serious harm.
•All modules of the Albalá Ingenieros TL3000 terminal line can be
hot-plugged or unplugged without suffering any damage or affecting the
processes that are currently taking place in other modules in the same
mounting frame. When a module is installed in an empty bay of a mounting
frame, it is necessary to mount the rear board that is part of that module.
Prior to installing this board, the mounting frame must be disconnected
from the power supply network. This is required because in addition to the
risk of electrocution for the person handling the device it is possible that a
high instantaneous current coming from the power supply could damage
the connectors and components of the mounting frame and/or the rear
board.
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Albalá Ingenieros | Manual ASW3000C01
•The ASW3000C01 module and the mounting frame should always be
installed, maintained, operated and removed by personnel with sufficient
technical qualifications. The equipment should never be placed in damp
areas, near splashing liquid, or in explosive or corrosive atmospheres.
Neither modules nor mounting frames can be used in applications that
could endanger human life.
3.3. Environmental considerations
This symbol indicates that this equipment must be deposited at a collection
point for proper waste treatment once it has reached the end of its useful
life.
3.4. Power considerations
The UR3000 and UR3100 mounting frames can house as many ASW3000C01 modules
as will fit in them.
3.5. Installing the module in the mounting frame
The steps needed to install the ASW3000C01 module with the rear board in the
mounting frame are:
1 - Disconnect all power cords from the power supplies of the mounting frame.
2 - Install the ASW3000P02 rear board ensuring that its 12-pin connectors are properly
aligned with the mounting frame´s mating connectors. Check that the orientation of
the board is correct by looking at the placement of the text printed on it according to
the illustration below.
3 - Remove the blank panels covering the front and rear of the empty bays chosen for
installing the ASW3000C01 in the mounting frame.
4 - Attach the rear board to the mounting frame with two M3 metric screws and tighten.
5 - Insert the ASW3000P01 board (main board of the ASW3000C01 module) into the
front of the mounting frame. The edges of the card slide into two plastic guides inside
the mounting frame.
6 - Affix the main board to the mounting frame using the two screws included on the
front panel.
After these steps, the module is ready to be connected to other equipment.
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Albalá Ingenieros | Manual ASW3000C01
Details for installation of the module in 3 RU mounting frames
Details for installation of the module in 1 RU mounting frames
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Albalá Ingenieros | Manual ASW3000C01
3.6. Interconnection
The following figure shows the ASW3000C01 module rear board connector layout.
Rear view of the ASW3000C01
The ASW3000C01 module provides two DVB-ASI digital video inputs (MAIN IN and RSV IN)
and four DVB-ASI digital video outputs (OUT1p,OUT2,OUT3 and OUT4). It also provides
five GPIO inputs/outputs, (GPIO1 to GPIO5).
The connector labeled OUT1p is protected by a bypass relay such that during power
supply failures or extraction of the module the MAIN IN signal maintains continuity.
The rear interconnection board is not designed to withstand mechanical stress. The
wiring must be fastened properly to the frame where the mounting frame is housed to
prevent the rear board from supporting the weight of the cables.
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Albalá Ingenieros | Manual ASW3000C01
3.6.1. Electrical DVB-ASI video connections
All DVB-ASI digital video electrical connections are BNC type. Below are several
recommendations to consider when wiring electrical signals.
BNC connectors used on cables must be suitable for the high frequencies of DVB-ASI
digital video signals: it is strongly recommended to use high quality connectors from
well known manufacturers.
All coaxial cable used must be Belden 8281 or similar. This type provides the greatest
lengths because it is used to calculate the equalizers in the ASW3000C01. Cables
carrying signal between the module and the devices should use single piece
construction, avoiding spliced sections with double BNC female or barrel connectors.
If it is necessary to split the cable into two sections the same type of wire should be
used in both sections.
The use of analog video coaxial cables (RG-59 type or similar) is not recommended for
digital video except for very short distances.
3.6.2. GPIO connections
The GPIO inputs use 3.81mm pitch terminal block connectors are have the following
equivalent circuit:
Before making any connections to these signals consult the table of maximum levels
in the specifications section of this manual. Never connect hazardous voltages to the
GPIO inputs.
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Albalá Ingenieros | Manual ASW3000C01
The lines indicated as GPIO n the silkscreening are assigned as follows:
GPIO5: Error input for the reserve channel.
GPIO4: Error input for the main channel.
GPIO3: Alarm output for the reserve channel.
GPIO2: Alarm output for the main channel.
GPIO1: Indicates selection of:
0V main channel.
+5V reserve channel.
GND: Ground for the module.
During normal operating conditions the alarm outputs GPIO2 and GPIO3 are set to
logic low (transistor on) in order to signal an alarm condition and a no-alarm
condition via a logic high (open collector). This signaling polarity can be inverted using
the control software.
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Albalá Ingenieros | Manual ASW3000C01
4. OPERATION
This section describes the significance of the front panel indicators of the ASW3000C01
module and their remote control and monitoring ability.
4.1. Front panel description
The appearance of the front panel and the elements it contains are shown in the
following illustration.
Front panel of the ASW3000C01
The panel contains the following elements:
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Albalá Ingenieros | Manual ASW3000C01
In the INPUT FAIL box:
MAIN,
RESERVE: Red. These LEDs light up to indicate that an alarm condition has been
detected at the corresponding input.
In the INPUT SELECTION box:
MAIN,
RESERVE: Green. These LEDs light up to indicate the input selected for delivery to
the output.
In the SWITCH MODE box:
AUTO: Green. This LED lights up to indicate that Automatic switching has been
selected.
HALF AUTO: Green. This LED lights up to indicate that Semiautomatic switching has
been selected.
MANUAL: Green. This LED lights up to indicate that Manual switching has been
selected.
SEL: Pushbutton. Pressing this button changes the switching mode and the
input selected.
In the ALARM box:
FAILURE: Red. This LED blinks when a change to the signal source selected has
occurred. This also generates an audible beep (which can be masked).
RESET: Pushbutton. A quick press of this button stops the blinking of the LED and
the audible beep. In Semiautomatic mode a sustained press of this button
rearms the module.
4.2. Configuration from the front panel
Selection of the operating mode is performed via sustained presses of the SELECT button
in the SWITCH MODE box. In manual mode, quick presses of the button change the
selected input.
4.3. Functional description
The ASW3000C01 contains two man functional blocks: one that detects errors in the
DVB-ASI inputs and the other with the control logic used to determine which output to
use.
Each input circuit includes a deserializer and TS packet synchronizer that can analyze the
packets received as well as count them based upon their PID. This allows different error
conditions to be set for each input signal.
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Albalá Ingenieros | Manual ASW3000C01
Every error condition can be activated or deactivated independently. A logic OR of the
activated error conditions generates the overall alarm condition that governs the global
validity of the input. The alarm condition for each input is sent to the control logic and
activates a GPO line.
The control logic determines which input signal is connected to the outputs at any given
moment based upon the alarm conditions of the two inputs and the switching mode
selected.
The control and basic supervision of the ASW3000C01 can be done from the front panel.
The pushbutton and LEDs can be used to change the operating mode, select the input
and rearm the switching alarm condition. The front panel also indicates the alarm
condition for each input channel, shows which of the inputs is currently being routed to
the outputs and provides visual and acoustic indications when switching occurs.
For more detailed remote control and supervision of the module the control software
can be used as long as a communications controller module is installed in the same
mounting frame as the ASW3000C01.
4.3.1. The error conditions
The following is a detailed description of the error conditions that can be detected by
the ASW3000C01:
4.3.1.1. GPI input
The activation of the corresponding GPI indicates an error. The polarity of the signal
is user-configurable.
4.3.1.2. Absence of input signal.
This error condition is produced when the equalizer does not detect any signal at
the input.
4.3.1.3. Loss of synchronization of the transport stream.
The most important aspect during evaluation of the data quality in an MPEG-2
transport stream is acquisition of the sync signal. The ASW3000C01 uses the
criteria outlined in the ETSI TR 101 290 V1.2.1 (2001-505) standard.
Synchronization is considered correct when five consecutive stream packets are
received and each has a correct synchronization word. A synchronization error is
produced when two or more packets with errors in their synchronization words are
detected.
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Albalá Ingenieros | Manual ASW3000C01
This condition corresponds to 1.1 TS_sync_loss as per ETSI TR 101 290 V1.2.1
(2001-05).
Once synchronization with the stream is established an analysis of the other
parameters becomes possible. If the presence of a sync signal is not detected and a
lock to that signal is not achieved then none of the other parameter analyzed are
valid. Therefore this alarm condition should never be deactivated by the user.
4.3.1.4. Error in the sync byte of the packets
This error condition is activated when no sync byte (0x47) in the transport stream
packets is detected after 188 or 204 bytes.
This condition corresponds to 1.2 Sync_byte_error as per ETSI TR 101 290 V1.2.1
(2001-05).
4.3.1.5. PAT errors
This error condition is the logic OR of various anomalous situations:
-No packets with PID equal to 0x000 (PAT) and with their table_id equal to 0x00
are detected within a programmable interval from 40ms to 10 seconds.
-Packets are detected with a PID equal to 0x000 (PAT) and a table_id other than
0x00.
-Packets are detected with a PID equal to 0x000 (PAT) and a
scrambling_control_field other than 00.
- The CRC of the PAT is incorrect (versions 1.7 and above).
These conditions correspond to 1.3.a PAT_error_2 as per ETSI TR 101 290 V1.2.1
(2001-05). The standard establishes a maximum time period of 0.5 seconds
between PAT packets, meaning that at least this much time is needed to detect this
error. The error detection interval can be reduced down to a minimum of 40ms.
4.3.1.6. Continuity error in the PAT packets.
The continuity counter of the TS packets with a PID of 0x0000 (PAT) fails to
correlate.
This condition corresponds to 1.4 Continuity_count_error as per ETSI TR 101 290
V1.2.1 (2001-05) with regards to the PAT packets. This check is not performed on
the remaining packets.
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