Siemens ST950 User guide

ST950

Intersection controller

siemens.co.uk/traffic

ITS Detection Solutions

ST950 Intersection controller

The ST950 is the latest in a long line of highly successful
intersection controllers from Siemens. Building on more
than 30 years of microprocessor based traffic controller
design, the ST950 family offers both familiarity and many
exciting new user and maintenance features.

With integrated UTMC based UTC SCOOT, Stratos Remote
Monitoring and MOVA functionality it offers great flexibility,
providing Intersection, Pelican, Puffin and Toucan methods
of control, at both LV (230V) and ELV (40V, 42V and 48V)
output drive level options.

The controller family is compatible with the whole range of
Siemens street-furniture, including Helios CLS LED traffic
signals, LED nearside signals and LED wait indicators, which
all offer significant power and cost savings compared with
conventional incandescent solutions.

Fully integrated UTMC and MOVA 7 functionality

Using a powerful ARM microprocessor core, the ST950 is
able to offer fully integrated UTMC and MOVA functionality
utilising advanced IP communications to the central office,
without the need for additional outstation equipment. Up
to 4 MOVA streams and up to 64 detectors per MOVA
stream are supported.

Each stream is configured using the familiar MOVA set-up
program and communication with MOVA is achieved via an
IP link using MOVACOM. MOVA is also available via the
controllers web browser interface which offers a MOVACOM
like function, allowing MOVA to be accessed remotely and
via non PC devices such as tablets or mobile phones.

MOVA data-sets are able to be changed either locally or
remotely without impacting the running controller on­street. A MOVA mode is also provided by the controller,
explicitly enabling MOVA control to be reported back to an
associated instation system.

Full UTMC OTU functionality is also supported using the
same principles and offering a similar user experience to
that provided by the Stratos Outstation, minimising user
retraining.

Full Stratos Remote Monitoring functionality is provided
allowing detailed site fault reporting, via the Stratos
system. Remote Monitoring, UTC SCOOT and MOVA
functionality are all able to be used together, as dictated by
traffic engineering needs.

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The controller may be specified to include an additional 2U
equipment rack, which neatly houses the chosen IP
communication router or modem, providing for example,
ADSL, Fiber or 3G communications to the central system.

Easy to use user interfaces

To simplify user interaction with the controller, the ST950
provides an extensive web browser interface which is
accessible either locally or remotely. Offering a consistent
style and where appropriate consistent functionality with
the free standing GEMINI UTMC OTU, this interface is able
to be accessed locally via a USB port on the controller CPU,
via Ethernet (if a communications router is provided) or via
a simple plug-in Wi-Fi interface module.

If necessary the ST950 may be configured to require PKI
certificate access. If enabled, only users who are in
possession of the valid certificate are able to make changes
to the controller data and all such changes are recorded,
along with the name of the person making the changes.

Related data items are conveniently grouped together so
that data changes can be made with the minimum of
page-changing. The interface fully manages the control of
level 3 data items and will actively prevent these from
being changed remotely (as required by TR2500), whilst
ensuring that other changes are able to be made simply
and efficiently.

ITS Detection Solutions

• Fully integrated UTMC OTU and MOVA 7
functionality

• Fully integrated Stratos Remote Monitoring

• Easy to use web based user interface

• Inbuilt live graphical site map

• Unique audible feedback of controller operation to
ease on-street maintenance activities

• Multi-Language capability

• Local and remote user access with optional PKI
security and user action logging

• LV (230V) and ELV (40V, 42V and 48V) lamp drive
systems

• Up to 32 phases, 32 stages and 8 independent
streams.

• Up to 240 digital inputs/output lines

• Integral lamp monitoring of all phases and signal
colours

The browser interface is capable of supporting multiple
languages and new languages are able to be easily added
to the system as required.

The interface also supports a live site map which shows the
status of key items, such as phases and detectors in real
time on a graphical representation of the site.

Signal heads may be shown as aspect displays or as STS
representative symbols allowing users to easily appreciate
the whole site operation in real time. Data for the map
display may be configured locally or imported from the IC4
Emulator tool.

A standard TR2500 25-way serial handset port is also
provided and many controller features are able to be
altered using the traditional Siemens handset mnemonics
if required.

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ITS Detection Solutions

Integrated LV (230V) and
ELV (40V, 42V and 48V)
lamp switching

The ST950 retains the robust and
proven lamp switch designs of the
ST900 family.

When configured as a standard 230V
controller the ST950 supports both
High Intensity incandescent lamps and
also LED signals. Where LED signals are
used, specially adapted lamp switch
cards provide reliable switching and
lamp monitoring, particularly for
Siemens Helios LV CLS LED signals.

• Modular construction -available in an outercase or as a 19 inch, 6U rack

• Simple installation - easily retro-fitted to existing controller cabinets

• Dual processor safety system

• Separate ‘applications’ processor

• Multi-mode operation including advanced ‘ripple’ stage change
algorithm

• Supports configuration changes with signals on

• Fully approved to UK Highways Agency specification TR2500 and TR2513

The ST950 ELV implements the proven
Siemens full wave rectified ‘DC’ system
which offers a wide range of benefits,
including:

• Increased electrical safety for
members of the public in the event
of damage to the signal installation

• Increased electrical safety for
personnel working on or around the
intersection

• Reduced power costs

• Reduced cabling costs

• Reliable lamp monitoring of very
low power LED traffic and
pedestrian signals

• Low supply current in-rush versions
minimising supply fusing and
supply capacity requirements

To deliver these benefits, the ST950
ELV incorporates many unique design
features including:

Use of a fully rectified ELV supply:
The use of a full wave rectified ELV
supply allows very efficient
semiconductor switches to be used,
reducing unnecessary heating effects
in the controller, contributing to
improved reliability and lower power
consumption.

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Active short circuit protection on all
outputs: Often the most frequently

damaged components within a traffic
controller are the output drive
switches, which are particularly
vulnerable to cable faults and short
circuits. The ST950 ELV design
incorporates an active short circuit
protection system on all lamp outputs,
ensuring that even under direct short
circuit conditions, the outputs are
protected from damage.

Active residual current quench on all
outputs: The power requirements of

LED-based street furniture are
becoming ever lower. As this occurs,
there is an increased risk that stray
and residual voltages, remaining
present after a signal is switched off,
will cause the controller to register
conflict or correspondence faults
incorrectly. The ST950 ELV is ready
today to deal with the very low power
signals expected in the future, as each
output is equipped with an active
circuit that eliminates these stray
voltages, without wasting power
when the signals are switched on.

Intelligent lamp switch system: The
ST950 ELV provides an intelligent lamp
switch card that implements full
voltage monitoring on each of its 32
outputs, using two separate safety
systems. Current and voltage
monitoring on each output is also
provided, so that any output may be
used for any signal colour.
Additionally, ELV LED traffic signals as
well as LED nearside and LED wait
indicators can be monitored directly,
without the need for any additional
intelligence in the signals themselves.
This high degree of flexibility allows
output use to be optimised, for
example, only using a single drive for
green arrows, making the most
efficient use of the available controller
hardware.

By default ST950 ELV controllers
provide a nominal 48V lamp drive
level, reducing to 27.5V when the
signals are dimmed. Optionally the
controller can provide either 40V or
42V drive levels, by the provision of an
alternative ELV output transformer.

The ST950 retains
the robust and
proven lamp switch
designs of the
ST900 family.

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