Union Switch & Signal Microlok II Operating and installation instructions

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©
2004 Union Switch & Signal India. All Rights Reserved. July 2005
PRINTED IN INDIA Revision Number: 1.3
UM-6800A
FUNCTIONAL DESCRIPTION
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PRIOR WRITTEN CONSENT OF USSI.

USSI Microlok II Functional description
UM-6800A Rev1.3 July 2005 Page 1 of 27
DOCUMENT APPROVAL RECORD
This Issue Authored By: A.Muruganantham Date: 19 July 2004
Title of Author: Design Engineer
This Issue Approved By: G.Perumalsamy Date: 19 July 2004
Title of Approver: Design Manager
DOCUMENT CHANGE RECORD
Issue No: Reason For Change: Date of Revision
1.0 Draft for review 27 July 2004
1.1 Internal review comments 04 October 2004
1.2 Initial Issue to SECR 12 October 2004
1.3 Board Diagrams added 04 July 2005

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MANUAL CONTENTS
1.1. INTRODUCTION _____________________________________________________________ 4
2.1. SYSTEM OVERVIEW__________________________________________________________ 4
3.1. SYSTEM DESCRIPTION _______________________________________________________ 5
4.1. MICROLOK II HARDWARE_____________________________________________________ 5
4.1.1. ENVIRONMENTAL __________________________________________________________ 6
4.1.2. PHYSICAL ________________________________________________________________ 6
4.1.3. CARDFILE ________________________________________________________________ 6
4.1.4. CPU BOARD_______________________________________________________________ 6
4.1.5. POWER SUPPLY BOARD ____________________________________________________ 9
4.1.6. PHYSICAL I/O_____________________________________________________________ 10
4.1.7. VITAL CUT-OFF RELAY ____________________________________________________ 16
4.1.8. ADDRESS SELECT PCB ____________________________________________________ 16
4.1.9. KEYING PLUG ____________________________________________________________ 17
5.1. SERIAL I / O________________________________________________________________ 17
5.1.1. MICROLOK PROTOCOL ____________________________________________________ 18
5.1.2. GENISYS PROTOCOL ______________________________________________________ 19
6.1. MICROLOK II SOFTWARE ____________________________________________________ 19
6.1.1. EXECUTIVE SOFTWARE ___________________________________________________ 19
6.1.2. APPLICATION SOFTWARE__________________________________________________ 20
7.1. MICROLOK II VITAL DIAGNOSTICS ____________________________________________ 20
8.1. SYSTEM OPERATING MODES ________________________________________________ 21
8.1.1. NORMAL MODE ___________________________________________________________ 21
8.1.2. SELECTIVE SHUTDOWN MODE _____________________________________________ 21
8.1.3. USER SELECTIVE SHUTDOWN MODE ________________________________________ 21
8.1.4. COMPLETE SHUTDOWN MODE _____________________________________________ 21
8.1.5. RESET MENU MODE_______________________________________________________ 22
8.1.6. CONFIGURATION MODE ___________________________________________________ 22
8.1.7. BOOT MODE _____________________________________________________________ 22
9.1. LOGIC PROCESSING ________________________________________________________ 22

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10.1. SYSTEM LOGS ___________________________________________________________ 22
10.1.1. SYSTEM EVENT LOG ______________________________________________________ 23
10.1.2. SYSTEM ERROR LOG______________________________________________________ 23
10.1.3. SYSTEM USER DATA LOG __________________________________________________ 23
10.1.4. SYSTEM MERGED EVENT LOG______________________________________________ 23
11.1. SYSTEM SPECIFICATION __________________________________________________ 24

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1.1. INTRODUCTION
This manual provides the following information about the Microlok II system.
• System level application and operational descriptions
• System component specifications
This manual is to be referred in conjunction with the Microlok II service
manual SM6800A.
2.1. SYSTEM OVERVIEW
The Microlok II system operation is controlled by proprietary executive
software running on the system hardware. The user application logic is
written in a proprietary Microlok II programming language and is compiled by
a proprietary compiler into a set of data tables which are interpreted by the
executive software during run-time.
The high-level block diagram of the Microlok II system is shown below. The
system uses diversity and self-checking concepts in which critical operations
are performed in diverse ways, using diverse software operations and critical
system hardware is tested with self-checking operations. Permissive outputs
are allowed only if the results of diverse logic operations correspond and the
self-checks reveal no failures. It uses a combination of vital and non-vital
hardware, and an executive software performing critical operations on the
site-specific application logic tables using dual-path processing and double
storage techniques along with continuous monitoring of the hardware
through the use of extensive built-in diagnostics. Any failure in any critical
portion of the equipment will result in the controlled system returning to a
safe state.

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Figure-1
3.1. SYSTEM DESCRIPTION
The Microlok II interlocking system is a multi-purpose monitoring and
control system, which performs the following.
• Drive Signal, Point, Crank Handle, LC Gate and Siding control relays
• Monitoring of Point position, track circuits occupancy and other field
inputs
• Vital CPU for overall system monitoring, control, diagnostics and data
recording
• Executive and application logic for vital interlocking functions
• Executive and application logic for non-vital control Panel & Operator
VDU functions
• Serial I/O channels for communicating with MLK II to MLK II, MLK II to
CAB/ Other Non-Vital application, Maintenance and Diagnostic function
4.1. MICROLOK II HARDWARE
The Microlok II system consists of modular card file-mounted equipment and
external peripheral devices that are used to interface the card file circuitry to
the field gears and other associated control systems. The following sections
provide an overview of the hardware.
Block Diagram of MICROLOK II System
Vital Conditional
Power Circuit
Microprocessor-
based Computer
System with vital
Software
Vital
Clock
Signal
Vital Input
Monitor
Vital
Inputs
Control
Signal
Output
Device
Control Vital Outputs
Vital Output
Monitor
Vital Output Power
Monitor

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4.1.1. ENVIRONMENTAL
• The Microlok II product will operate in a standard railway environment
• The system operates in ambient temperature ranges of –40 to +70 degrees
centigrade. This refers to the temperature outside the card file but inside
the relevant building enclosure
• The system operates from 0 to 95% non-condensing humidity
• The system meets the required EMI specification
• The system meets the required vibration specification
4.1.2. PHYSICAL
• The card file is 16.75” wide and it can be mounted in a standard 19” rack
• Boards in the card file include a faceplate where status information will be
displayed. A blank panel will be available to cover empty slots
• The system will accept power from an external battery in the range of 9.8V
DC to 16.2V DC for an internal conversion to the required voltages
• The internal power converter will have a start-up voltage requirement of
11.5V DC to inhibit start-up when the battery voltage is low
• Nominal 24V input/output boards will have an input/output supply in
the range of 19.6V DC to 32.4V DC
4.1.3. CARDFILE
The Microlok II card file is a G64/96 bus based card file that holds the CPU,
Power Supply & Variety of I/O boards. The card file will be a user
configurable. The Microlok II card file is designed to house standard 6UX220
Euro card plug-in printed circuit boards. The card file will have twenty slots.
• Slots No. 1 to 15 & 20 are used to accommodate Non-Vital or Vital I/O
boards.
• Slot No. 16 & 17 are reserved for Power Supply board.
• Slot No. 18 & 19 are reserved for CPU board.
4.1.4. CPU BOARD
The CPU board is controlled by a Motorola 68332 microprocessor, which
operates at a speed of 21 MHz, and includes 2K bytes of internal fast
termination RAM. Most internal operations are 32 bits wide, while all outside
bus cycles are 16 or 8 bits wide. The executive and application software is
stored in four flash EPROMs that provide up to 8MB of memory. Flash
EPROMs permit direct handling of the executive and application software
using a PC connected to the CPU board front panel serial port connector.
Jumpers are provided on the board to enable or disable the flash EPROMs for

USSI Microlok II Functional description
UM-6800A Rev1.3 July 2005 Page 7 of 27
programming and to select the required programming voltage. The CPU board
contains the central controlling logic and diagnostic monitoring for the
Microlok II system, and provides five serial data ports. The CPU connector
housing has an internal EEPROM that is used to store site-specific
configuration data. Even if the CPU board is replaced, the configuration data
remains intact within the CPU connector’s EEPROM.
• Ports 1 and 2 support an RS-485 hardware interface
• Port 3 supports an RS-423 & RS 232 interface
• Port 4 & 5 supports an RS-232 interface
Figure – 2
ADJUST
UP
DOWN
REJECT
ACTION
ACCEPT
RESET
DOWN
UP
L R
M
E
N
68332
CPU
ON-LINE
VPP ON
RESET
E
D
C
B
A
2
4
5
3
1
7
8
6
1234
CAB D
DTE
RS-232
13
12
11
8
4
1
10
9
7
6
5
3
2
U

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CPU Function
• Monitoring external inputs from vital input boards and non-vital input
boards
• Processing vital external inputs and executing logic defined in the
application software
• Driving vital output boards as required by the application program
• Monitoring and controlling serial communication ports (links to other
controllers)
• Testing individual vital input and output channels for faults (in parallel
with control of these channels) and responding to detected faults
• Monitoring system internal operation for faults and responding to detected
faults
• Controlling power to vital outputs through the card file power supply and
an external VCOR (fail-safe function)
• Recording system faults and routine events in user-accessible memory
Fig. 2 Ref Label Device Purpose
1, 2 (None) 4-character alpha-
numeric displays On-site configuration programming menus and options.
3 A, B, C, D, E Yellow LEDs Reserved for serial link status.
4 1, 2, 3, 4, 5, 6, 7, 8 Red LEDs User-defined in application software.
5 ON LINE Green LED When lit, indicates normal system operation
(successful diagnostics).
6 VPP ON Yellow LED When lit, indicates FLASH +5V or +12V
programming voltage enabled (via board
jumper).
7 RESET Green LED When lit, indicates that the system is in reset
mode.
8 RESET Momentary pushbutton When pressed, resets the CPU. Also used to
place the CPU in the reset mode.
9 MENU L-R 3-position (return-to-
center) toggle switch Used to search main program menu items shown on displays.
10 MENU UP-DOWN 3-position (return-to-
center) toggle switch Used to select main program menu items shown on displays.
11 ADJUST UP-DOWN 3-position (return-to-
center) toggle switch Used to cycle through configuration values to
be selected with “ACTION” switch.
12 ACTION ACCEPT-
REJECT 3-position (return-to-
center) toggle switch Executes or cancels configuration value
selected with “ADJUST” switch.
13
RS-232 DTE
Diagnostic Link
Connector
DB9, RS-232 Connector
(DTE) Used for connection to Maintenance PC for System monitoring diagnosis.

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UM-6800A Rev1.3 July 2005 Page 9 of 27
• Responding to CPU board front panel switch inputs and operating the
associated displays
• Interacting with a laptop PC during system diagnostic operations,
application logic programming, and executive software upgrading
4.1.5. POWER SUPPLY BOARD
The Power supply board will have double width housed in the card file and it
operates in the range of 9.5V to 16.5V DC producing 5V at 3amps and +12V
at 1amp that are needed for the operation of the card file circuitry. The power
supply will have a start–up voltage requirement of 11.5V DC. This prevents
the unit from attempting a recovery when battery voltage is low. The power
supply board performs the following functions:
• Converts the external supply voltage (9.8V to 16.2V DC) to regulated +12V
and +5 for outputs to the system card file internal circuits
• Supplies energy to the VCOR relay coil under the control of the CPU board
The power supply board serves a vital role in the fail-safe design of the
Microlok II system. The regulated +12V and +5V power is distributed to all
system card file boards through the card file back plane bus.

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Figure - 3
Fig. 2-2 Ref Label Device Purpose
1 5V ON LED (green) When lit, indicates 5V-operating power on to other
Cardfile PCBs (If not lit refer to Figure-2.2.1).
2 VCOR LED (green) When lit, indicates conditional power on to VCOR relay
(CPU diagnostics normal). (If not lit refer “CPS CLEAR
FUNCTION” details in Figure-3.4).
4.1.6. PHYSICAL I/O
The Physical I/O characteristics have been chosen to accommodate normal
railway and transit interface devices. Requirements for standard 24V DC
battery supply, Vital and Non-Vital relays, lamps and LED indications have
all been taken into account in determining voltage and current limits. The
voltage and current ranges specified for each I/O type are based on the
minimum and maximum requirements for these devices. The supply voltage
POWER SUPPLY
5V ON
VCOR
1
2

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is assumed to be the maximum high voltage or minimum low voltage
depending on which would cause the worse case for reliability and safety
considerations.
Response times for railway and transit application have historically been
specified in the 100msec to 1second range. The response times for Microlok
II, based on older products, allows for fast response to state changes while
allowing filtering time for reliability reasons. In addition, it must be
recognized that some processing may be delayed by other system tasks. In
cases where such delays can impact system safety, such as delivery of
outputs within 200msec or reading of inputs within 400msec, the maximum
tolerable delay time is specified in the requirements.
Non-Vital I /O Board
The Non-Vital I/O board is designed to receive non-vital inputs (controls) and
generate non-vital outputs (indications). The version of the NV.IN32.OUT32
board connects each of its 32 inputs and outputs to a 96-pin connector
mounted on the rear of the board. The board employs polyswitches to protect
the output circuitry. A polyswitch functions like an auto circuit breaker.
When the over current trip point (about 0.75 amp) is exceeded, the device
switches to high impedance. The polyswitch returns to low impedance when
the overload or short circuit condition is removed. Inputs on the boards are
activated from a positive voltage relative to battery ground over a range of 6
to 30V DC. The non-vital I/O boards use latch ICs to buffer inputs and field
effect transistors to drive outputs.
• The minimum ON threshold for a Non-Vital Input will be 4.5V DC for
nominal 24V DC systems.
• The maximum OFF threshold for a Non-Vital Input will be 2V DC for
nominal 24V DC systems.

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Figure – 4
Fig. 4 Ref Label Device Purpose
1
INPUTS 1-32
Green LEDs Monitors states of non-vital inputs 1-32.
When LED is lit, respective input is on.
2 OUTPUTS (SWITCHED TO
N12) 1-32 Yellow LEDs Monitors states of non-vital outputs 1-32.
When LED is lit, respective output is on.
Vital Output Board
Outputs are controlled by “high side” software-controlled switches. Loads
should be connected from outputs to battery negative. The high side switch is
used to connect battery (+) to the output. Each output is protected with a
polyswitch, which acts like an auto circuit breaker. When the over current
trip point is reached (approximately 0.75A), the polyswitch switches to a high
impedance state. The switch resets to its low impedance state when the
additional load or short is removed. A short to battery (-) will trip the
NV.IN32
1
1
2
3
4
7
8
5
6
11
12
10
9
16
14
15
13
INPUTS
16
15
13
14
12
10
11
9
7
8
6
TO N12
3
4
5
1
2
SWITCHED
OUTPUTS
32
31
29
30
28
26
27
25
23
24
22
19
20
21
17
18
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
.OUT32
2

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UM-6800A Rev1.3 July 2005 Page 13 of 27
polyswitch and cause the VCOR relay to drop, but will not cause any
damage. A short to battery (+) will not cause any damage, but since this
condition is equivalent to a false output, the Microlok II CPU will cause the
VCOR relay to drop.
• Each Vital Output PCB is having 16 outputs.
• Each output is assigned to the final relay which is driving the outdoor
signalling gears such as HR, DR in case of signal & WNR, WRR in case of
points.
• Since the output boards are driving outdoor gears, they are continuously
monitored by the CPU and any abnormal voltage present in the output will
lead to system reset / shutdown to ensure safety
Figure – 5
OUT16
OUT 16
OUT 15
OUT 14
OUT 11
OUT 13
OUT 12
OUT 10
OUT 3
OUT 7
OUT 9
OUT 8
OUT 5
OUT 6
OUT 4
OUT 1
OUT 2
2
1

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Fig. 5 Ref Label Device Purpose
1 OUT1 -OUT8 Yellow LEDs Monitor state of vital outputs 1 through 8. When lit,
indicates respective output is turned on.
2 OUT9 -OUT16 Yellow LEDs Monitor state of vital outputs 9 through 16. When lit,
indicates respective output is turned on.
Vital Outputs
The Vital Outputs are designed primarily to interface with vital relays. In
typical railway and transit applications, most Vital relays are specified to use
nominal 24V DC supply voltage.
• The minimum voltage for a Vital Output in the ON state will be 95% of I/O
supply battery for 24V DC outputs.
• The maximum voltage for a Vital Output in the OFF state will be such that
a Vital relay will not remain picked at the current produced. This voltage
is 1.5V DC for a 24V DC output.
• The output will be capable of driving a minimum output load of 100Ωfor
the 24V DC outputs.
Control of outputs
Each output is controlled by the processor and monitored by a circuit
providing feedback to the processor to ensure that the output is indeed what
was requested by processor. Also, to check the integrity of the feedback loop,
the outputs are cycled on a periodic basis. If an output is currently turned
on, the processor will turn it off for an instant and verify the correct response
from the monitor. Failure of these checks would result in a system shutdown
and reset. See the figure-1.
Vital Input Board
There are no power connections required through the upper connector. When
wiring a vital input PCB to a relay contact circuit contained in the same
house of the Microlok II card file, the signal battery may be used as the
energy source to activate the inputs. Terminals designated (-) may be
connected to battery N24 and B24 switched over relay contacts. When wiring
a vital input PCB to a relay contact circuit outside the Microlok II house, use
the isolated source that is part of the power supply. This is consistent with
the practice of confining signal battery to the case in which the Microlok II
unit is housed.
• Each Vital Input PCB is having 16 Inputs.
• Each input is assigned to the detection of outdoor gear status such as
ECRs in case of signal, WKR incase of points & TPR in case of Track.

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UM-6800A Rev1.3 July 2005 Page 15 of 27
• Since the vital inputs are dealing with the detection of outdoor gears they
normally configured with double cutting arrangement.
Figure – 6
Fig. 6 Ref Label Device Purpose
1 IN1 -IN8 green LEDs Monitor state of vital inputs 1 through 8. When lit, indicates
respective input is turned on.
2 IN9 -IN16 green LEDs Monitor state of vital inputs 9 through 16. When lit, indicates
respective input is turned on.
Vital Inputs
Vital inputs, which are in most cases, derived from the battery supply must
have the same range of inputs as the supply battery. To ensure reliable
operation, the Minimum ON thresholds (the levels above which an input
must read ON) were chosen to match the low ends of the battery ranges. The
IN16
1
IN 1
IN 2
IN 3
IN 4
IN 5
IN 6
IN 7
IN 8
IN 11
IN 15
IN 16
IN 13
IN 14
IN 12
IN 9
IN 10
2

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only criteria for selecting the Maximum OFF thresholds (the levels below
which an input must read OFF) are that they must be below the Minimum
ON threshold, yet high enough above 0V to reject induced noise. The system
will have the ability to access Vital Inputs even when the system is running
with the Vital Outputs in an un-powered state. Since the most restrictive
state for the inputs has already been defined as the de-energized state, failed
inputs can safely be set to this state. This allows the system to react to the
failed input without causing a Critical Error. This may cause the system to
run in a downgraded state due to the OFF input state, but will cause no
safety-related failures. The failed input status is available to the Application
Logic such that the Application Developer may take other action as required
by a particular system in the case of a failed input.
• The minimum ON threshold for inputs will be 19.6V DC for 24V DC
inputs.
• The maximum OFF threshold for inputs will be 9.0V DC for 24V DC
inputs.
Control of inputs
A principle similar to that used for the output circuitry is employed in the
input interface circuitry. De-energizing of any input results in a more
restrictive condition. All individual input interface circuits on a given board
are forced to the more restrictive state through the closed loop vital input
monitors. The inputs are then read and verified that they can, in fact, be
forced to the more restrictive state. This is ensure that no interface circuit
malfunction have occurred that could place an input in a less restrictive
state. See the figure-1.
4.1.7. VITAL CUT-OFF RELAY
The vital cut-off relay (VCOR) contacts are used to control the power to all
card file vital outputs. The VCOR is controlled by the CPU board. The CPU
board performs continuous diagnostics, to include monitoring of all vital
output and input channels at the point of interface with external circuits.
This CPU responds to failure of a safety-critical diagnostic by commanding
the CPS on the power supply board to remove the DC supply to the VCOR
coil, thereby opening the contacts that provide battery power to the vital
output boards. This fail-safe function defaults the interlocking equipment
associated with the Microlok II system to the most restrictive state. PN-150B
vital biased relay is used for the VCOR. This relay consisting of low voltage
silver-to-silver fronts and silver-to-silver backs contacts.
4.1.8. ADDRESS SELECT PCB
The address select jumpers are used for board addressing. The jumper
settings are automatically determined by the compiler after the successful

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UM-6800A Rev1.3 July 2005 Page 17 of 27
compilation of application program. This information is clearly defined and
available to the user in the listing file (.mll), which is one product of
compiling an application text file (.ml2). If this file is unavailable, the user
can determine the jumper settings by following the instructions below. By far
the best way to determine the jumper settings, however, is to use the list file.
The jumper settings for each board are determined by the order in which the
boards are defined in the application. The jumper settings do not depend on
the order of the boards that happen to appear in the card file. If the
application program and list file are both unavailable, then the order can also
be found by looking at the configuration menu in the Microlok II
Maintenance Tool.
• Each address select PCB consists of 6 Nos. of jumpers.
• Each slot will have its own jumper setting and each one is different from
others.
• The address select PCB ensures the type of board used in the slot as
defined in the application logic.
• 48 pin address select PCB is used for vital boards & 96-pin address select
PCB is used for non-vital boards
4.1.9. KEYING PLUG
Each of the Microlok II card file slots includes a 12-way female keying guide
next to the 96-pin connector. The guide is used to ensure installation of the
proper circuit board in each card file slot after the complete card file board
configuration has been determined. Each board is equipped with a
corresponding 12-way male keying guide; individual keying tabs are removed
at the factory in a specific pattern for the board part number. Prior to
installing a board, insert keying plugs into the corresponding card file
motherboard keying guide. If it becomes necessary to change the type of
board installed in a given slot, the previously installed keying plugs can be
removed using a knife or a pair of needle nose pliers.
5.1. SERIAL I / O
• The system will support a minimum of three kind of active ports for
Application Interface processing that is RS-232, RS-423 and RS485
• All ports will provide, at minimum, Transmit (TXD) and Receive (RXD) data
signals and Request To Send (RTS) and Data Carrier Detect (DCD) control
signals. At least one port will provide a control input for Clear To Send
(CTS)
• All control lines for all ports will be accessible such that each port can be
modified to support different electrical properties without modification to
the base PCB on which the port resides.

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• The system will support the functions of both the master and slave of the
Microlok Vital protocol.
• The system will support the functions of both the master and slave of the
Genisys Non-Vital protocol.
• The Microlok and Genisys, master and slave protocols will be supported
on all ports.
• The system will allow protocols of the same type to be active on more than
one port.
• Only one link will be permitted to be active on a port at a given time. A
Critical Error results if more than one link is assigned to the same port.
5.1.1. MICROLOK PROTOCOL
• The Microlok protocol supports from 1 to 32 Serial Stations per link.
• The Microlok protocol will be capable of handling addresses between 1 and
127.
• The Microlok protocol supports Serial Stations having from 0 to 128 input
Boolean Bits and from 0 to 128 output Boolean Bits in the Application
Logic. There must be at least one input or one output Boolean Bit defined
for each Serial Station.
• The Stale Data Time-Out (SDTO) for the Microlok protocol will have an
allowable range of 0.100 to 25.000 seconds in 100 millisecond increments.
This time-out will be reset each time a valid message is received. This
information is included in the Application Configuration.
• At the expiration of the SDTO, all input bits for the Serial Station will be
set to 0 and the station’s System Status Variable will be cleared.
• The allowable range for the Polling Interval Timer will be 0 to 2.000
seconds in 10 millisecond increments. This Non-Vital information is
included in the Application Configuration.
• The allowable range for the No-Response Timer will be 30 to 5000
milliseconds in 10 millisecond increments. This Non-Vital information is
included in the Application Configuration.
• A less restrictive input (1 state) will not be asserted to the Application
Logic until it has been received in two consecutive messages.
• A more restrictive input (0 state) will be asserted to the Application Logic
after one message has been received.
• Outputs that are more restrictive will be latched and transmitted until
acknowledged by the receiver.