BT Redcare 5G Classic STU 11 pin Troubleshooting guide

User/Installation Guide
5G STU
LPS 1277: Issue 3
Cert No. 1270a
Cert No. 1270b

Product name BT item code
Redcare 5G Classic STU 11 pin 049926
Redcare 5G Classic STU 8 pin 076352
Redcare 5G Classic STU PLI 062843
Redcare 5G Fire STU 049927
Redcare 5G STU User/Installation Guide
This manual contains information on the BT Redcare 5G STU product range.
It contains more detailed information than that provided in the quick start user guide provided
with the STU.
Description
The 5th Generation Subscribers Terminal Unit (5G STU) is a communicator for signalling alarm signals between a protected
premises and an alarm receiving centre (ARC). The 5G STU uses the extremely reliable BT Redcare network to convey the
messages over a BT Redcare enabled BT analogue PSTN line. Even if an intruder cuts the line and jams the radio signals an
alarm message will still rapidly be sent to the ARC.
The 5G STU is fully compatible with BT’s 21CN network upgrade programme and connects to any BT Redcare enabled
telephone line.
The 5G STU is fully ADSL compliant and does not require an additional ADSL microfilter.
Fig 1. 5G Classic STU
TNV Cover
PL2
Debug Point
PL1
Serial Port
PL3 Sec/Ln PSTN + Earth
Connectors
LK1
Private Wire Link
Main Terminal Block TB1
Mode Key
Set Key
8 Segment
LED’s
Page 1

Pre-Installation Requirements
Before a 5G STU installation can commence, a BT Redcare Service Order must be submitted to BT Redcare by the Alarm
Receiving Centre. This ensures that the appropriate exchange connections have been made and a block terminal 92A has
been provided at the customer’s premises.
Mounting and Safety Statement
The 5G STU is designed for host-independent fitment.
The circuit board area, under the cover, is classed as a Telecommunication Network Voltage (TNV-3) circuit. All other
interconnection points are classed as Safety Extra-Low Voltage (SELV) circuits. It is only necessary for this cover to be
removed during installation of the PSTN wiring. A functional earth connection using CW1044 cable is required to the
terminal block TB5.
The host alarm panel or box into which the 5G STU is installed must provide a RESTRICTED ACCESS LOCATION in
accordance with the requirements of BS EN 60950.
The unit should be mounted inside the alarm panel, or inside a separate powered housing, using the sticky mounting pads
supplied.
For fire alarm panels the enclosure must meet the requirements of EN 54-21 7.3 (eg. IP30 or above) and the supplied
sticker should be applied to the outside of the housing (fig 2). Enclosure requirements for the 5G STU are the same as for
the fire alarm panel itself and must meet EN 54-2. The enclosure must restrict access to installer level 3. The enclosure
must provide the facility to indicate the state of the fault and acknowledge outputs on the
5G fire STU.
Fig 2. For fire installations apply a label to the outside of the STU enclosure.
For security installations the enclosure must meet or exceed the protection requirements of the particular security grade
for the whole installation as per EN 50131-1
Suitable user protection to ensure compliance with BS EN 60950 should be present on the host or its fitted
equipment. A hazardous voltage is one which exceeds 42.4V peak AC. or 60V DC. If you have any doubt, seek advice
from a competent engineer before installing this or other adapters into the host equipment.
EN 54-21:2006
5G FIRE
Page 2

Static Sensitive Devices
Static electricity is present in our everyday lives. A static charge is generated by friction, and whenever two
dissimilar materials are separated. The imbalance of electrons causes a potential difference of many hundreds of volts.
On discharge, a large current flows for a short time.
Many electronic components can be damaged by such static charges. Component failure may not be immediate
or catastrophic. Electro-Static Discharge (ESD) can cause hidden damage to components, which will affect their reliability.
It is recommended that precautions are taken against damage due to static electricity during the installation and
maintenance of the 5G STU. Suitable ESD protection measures include ensuring that you are earthed (via a wrist strap
and a 1M resistor) whenever you handle the unit.
Telephone Line Connections
Connect the 5G STU to the block terminal using standard telephone cable CW1308. Only one 5G STU may be connected
to any one telephone line.
WARNING: the block terminal contains telecommunication network voltages.
Please note that it is important to use the correct method of connecting the STU to the Block Terminal 92A.
The Block Terminal provides an insulation displacement connection (IDC) block for the incoming phone line.
No connections, other than those made by BT, should be made to this IDC block. The STU should be connected to
the screw terminals as shown. The 5G STU is not polarity conscious on its line terminals.
Power Supply
The 5G STU must be connected to a suitable power supply. The installer must ensure that the rating of the power supply
is greater than the combined rating of the 5G STU and any other apparatus drawing power from the power supply.
For use with intruder alarm panels the power supply must meet the requirements of EN 50131-6. For use with Fire
alarm panels the power supply must meet the requirements of EN 54-4 and the 5G STU must be mounted in the same
enclosure as the power supply from which it derives its power.
The 5G STU supply requirements are detailed later in this manual.
Fig 2: Block Terminal 92A
Page 3

REN
The Ringer Equivalence Number (REN) for the 5G STU is 1.0. As a guide to the number of apparatus that can be
simultaneously connected to a line, the sum of REN values for each apparatus should not exceed 4.0. A BT provided
telephone is assumed to have a REN value of 1.0 unless otherwise marked. If the 5G STU is used with an MCD, the
combined REN will be 1.5.
Training Courses
BT Redcare offer a free training course for installers of the BT Redcare service. For further information call General
Enquiries Tel: [phone]*.
* Calls are free to this number from BT landlines and BT payphones. However, they are not free to call from mobile phones - the costs will vary between service providers.
5G GSM STU Inputs
The STU has up to 11 screw terminal inputs plus tamper (T) & AC fail (F) for connection to the monitored equipment such
as an alarm panel (3 inputs on the Fire STU). The alarm inputs are triggered by changing their voltage state.
At default a positive voltage applied to the input will trigger an alarm condition. The polarity of the inputs can be
configured using the PP (Pin Polarity) menu.
For fire alarm panels the fire alarm notification output must be connected to the STU input numbered pin 1.
Pin 1 has an associated fire alarm acknowledgement message, received via the relay output labelled RPS.
A+ Terminals
The STU has 4 terminals marked A+. These terminals provide a 10K resistive connection to +V and can be used to trigger
the alarm inputs through relay contacts if required.
Output Relays
Three output relays are provided: Control, Return Path Signalling (RPS), and Line Fault. The use of any, or all, of these
functions is optional. For a basic installation these outputs are not required.
Note: If an output is to be connected to a device which produces transient voltages, such as a bell, the device should be
suppressed using a suitable protection diode.
For fire alarm installations the indication of ‘acknowledgement of fire alarm’ and ‘SPT fault’ messages must be provided by
the fire panel into which the SPT is mounted.
System fault indications which are notified by the 5G Fire line fault output relay ‘LF’ must be latched by the fire panel as
required by EN 54-21.
Control Output Relay (CTRL)
This relay can be switched on or off by the Alarm Receiving Centre (ARC) operator by sending an output ON or output OFF
command to the STU through the BT Redcare network.
The output can typically be used to remotely reset an alarm panel, or to operate other devices such as lights or door
latches at the site.
Page 4

Line Fault Output (LF)
The Line Fault Output is used to indicate that the communication path has failed at the protected premises.
The ‘Line Fault’ relay contacts (Normally Open, Common, Normally Closed) are available for connection on TB1.
The maximum current rating of the relay contacts is 1 Amp.
The LF relay will also activate if a pin alarm is not acknowledged by the ARC within 30s, or if the watchdog timer on the
STU activates.
The polarity of the LF relay can be set by configuring the F2 menu. The default state for the LF relay on the fire STU is
relay activated when path normal (F2=0). This ensures the LF relay will also change state on STU power failure. This
setting (F2=0) should also be used with all 5G STU’s.
Return Path Signalling (RPS)
The RPS output is used to indicate, at the protected premises, that the opening/closing signal has been sent to, and
acknowledged by, the Alarm Receiving Centre.
To use the RPS function, at least one of the alarm inputs must be designated as an opening/closing channel (usually
channel 4). The RPS output will activate when an opening or closing signal is detected. It will de-activate when the
opening or closing signal has been acknowledged by the Alarm Receiving Centre. It is allowable to have more than one
input designated as an opening/closing channel, but each must be acknowledged to de-activate the RPS output.
The RPS relay contacts (Normally Open, Common, Normally Closed) are available for connection on terminal block TB1.
To use this option, a warning device such as a piezo bleeper or external strobe light should be connected through these
contacts. The maximum current rating of the relay contacts is 1 Amp.
Fire ACK Output (RPS/ACK)
Fire STU’s with V4.1 S/W or later have the RPS output configured to act as an Acknowledge output to a pin 1 alarm, i.e.
the RPS/ACK relay will operate when an acknowledgement to a pin 1 alarm is received from the ARC, and the RPS/ACK
relay will release when an acknowledgement to a pin 1 reset is received from the ARC. If a pin alarm is sent from the STU
and not acknowledged within 30s then the LF relay will operate. This allows the STU to be wired as follows to meet the
requirements of EN 54 fire regulations.
Page 5

Typical Monitored Fire Alarm Panel Input 1
Configure LF to be normally energised F2 = 0 and use C – NO connection. This ensures a power fail to the STU will be
detected as a fault by the fire panel.
Configure the fire panel input for EN 54 100s Ack input.
As the input pins on the STU do not detect fault conditions, ensure the STU is fitted within the fire panel housing or in a
separate housing that is directly adjacent to the fire panel. This minimises the risk of faults on the interconnecting wiring.
STU Specifications
Pin alarm inputs:
Logic High = +2.5V to +30V
Logic Low = -0.5V to +0.8V
Logic level outputs:
Logic High = 3.0V @ 560µA max
Logic Low = 0.4V @ 280µA max
With respect to the 0V terminal on TB1.
Power rating:
5G Classic 12Vdc +/- 2V 80-100mAlow battery alarm 10.4V +/- 0.5V 60s delay
5G Fire 24Vdc +/- 4V 80-100mAlow battery alarm 20.5V +/- 0.5V 60s delay
Environmental:
Operating ambient temperature +5ºC to +40ºC
Relay contacts:
30V 1A Max
Physical:
Size = 168 x 115 x 36mm
Telephone Line Selection (LK1)
The 5G STU is supplied ready to connect to the Public Switched Telephone Network (LK1 is not fitted). If the 5G STU
is to be connected to a Private Wire (RedDIRECT) a suitable link must be fitted in the position marked LK1 under the TNV
cover. For RedDIRECT PW working the 5G STU must be configured with F3 set to 1.
Note the LK1 link provides 600 ohm line matching for PW working and is only generally used on legacy RedDIRECT
circuits or for test purposes. For normal PSTN connection LK1 is NOT required.
If you have any doubts about the type of telephone line to which the STU is being connected, contact BT Redcare for
advice.
Page 6

5G STU Displays
The current status of the STU is displayed on the 2 X 8 segment displays.
The STU will cycle through the messages in 1 second steps.
AL = This is followed by the ALarm pins that are active (in the Alarm state). 00 if no alarms are active, or the numbers of
the pins outstanding, i.e. 4 = pin 4 outstanding.
NC = Not Commissioned. The STU has yet to receive an UP STU command from the ARC.
5G STU Configuration
The 5G STU is factory supplied with the most common settings for most installations, so generally the unit can be
installed without the need to carry out configuration. However, if changes to the default setting are required they can be
carried out as follows.
Note: The 5G STU must be in the fully de-commissioned state to enter the configuration menu.
To enter the configuration menu press and hold the MODE button for 5 seconds.
PP will be displayed on the display.
The MODE button can be used to step cycle through the main menu as follows:
PP = Pin Polarity
OC= Message Select (Open Close)
iD = Set Hard ID number
PE= Pin Enable
F1 = Function digit 1 (Control Relay)
F2 = Function digit 2 (Line Fault Polarity)
F3 = Function digit 3 (Connection Type)
F4 = Function digit 4 (Line Monitoring Enable)
F5 = Function digit 5 (Serial Parallel)
LD = Load Default (Reset all variables to manufacturers default)
?? = Commit to microprocessor memory.
The SET button is used to enter the sub menu for each function.
Tip: Continually pressing the MODE button will always eventually return to the main menu and to the ?? exit point.
Tip: The main menu can only be exited at the LD or ?? prompts. (see these sections for exiting configuration mode).
Tip: If the state of configuration is unknown then it can be reset to the factory default settings from the LD load
default menu option.
Page 7

PP Pin Polarity
Pressing SET at the PP menu option enters the pin polarity sub menu.
At factory default all inputs are set to positive applied triggering.
The input pin polarity can be changed by using the MODE button to step through pins 1 to 11 t & F, and using the SET
button to toggle the input polarity for that pin.
The following display symbols are used to denote positive applied or positive removed triggering.
Once all pins have been configured, the MODE button returns to the main menu
OC Open Close Message Select
Pressing set at the OC menu option enters the Open / Close sub menu.
At factory default all inputs are set to send ALARM / RESET messages, except pin 4 that is set to send OPEN / CLOSE
messages. The message type for each pin can be changed by using the MODE button to step through pins 1 to 11, and
using the SET button to toggle the message type for that pin.
The following display symbols are used to denote the pin message type:
O = Open / Close
A = Alarm reset
Once all pins have been configured, the MODE button returns to the main menu.
iD Hard ID Number
Pressing SET at the iD menu option enters the hard ID sub menu.
At factory default the unit has the last 4 digits of the serial number as its Hard ID.
Tip: The 4 digit Hard ID forms part of the secure encryption key for signalling and there is generally no need to change
this number.
The 4 digit number is Hexadecimal and can be in the range 0001 to FEFF
Should a change be required the following procedure can be used.
When the Hard ID sub menu is entered, the first 2 digits of the current Hard ID are displayed.
A lit dot above the digit denotes the digit that will be changed with each press of the SET button.
The MODE button cycles to the next digit.
After setting the first 2 digits, the last 2 digits are displayed again with a lit dot to denote the digit that will change with
the SET button.
Once all 4 digits have been configured, the MODE button returns to the main menu.
Page 8

PE Pin Enable
Pressing SET at the PE menu option enters the Pin Enable sub menu.
At factory default the all inputs are enabled.
Tip: There is generally no requirement to disable inputs, unused inputs can simply be left disconnected.
Should a change be required the following procedure can be used.
The input pins can be changed by using the MODE button to step through pins 1 to 11 t & F, and using the SET button to
toggle the input to Enabled or Disabled for that pin.
The following display symbols are used to denote pin enabled or disabled.
= is enabled
_ is disabled
Once all pins have been configured, the MODE button returns to the main menu.
F1 Function 1 - Control Output Relay
Pressing set at the F1 menu option allows the Function 1 value to be configured.
At factory default the F1 digit is set to 0.
The function 1 (F1) value has the following functionality.
0 = Control output relay NOT energised at power up
1 = Control output relay energised at power up
Once the F1 value has been configured, the MODE button returns to the main menu.
F2 Function 2 - Line Fault Relay
Pressing set at the F2 menu option allows the Function 2 value to be configured.
At factory default the F2 digit is set to 1.
The function 2 (F2) value has the following functionality.
5G Classic STU
0 Line Fault relay de-energised when landline path has failed.
1 Line Fault relay energised when landline path has failed.
Once the F2 value has been configured, the MODE button returns to the main menu.
Page 9

Connection Type On-hook Off-hook
0 PSTN 0 dB -3 dB
1 PW 0 dB 0 dB
2 PSTN 0 dB 0 dB
3 PSTN 0 dB -6 dB
4 PSTN 0 dB -9 dB
5 PSTN -3 dB -3 dB
6 PSTN -3 dB -6 dB
7 PSTN -3 dB -9 dB
Connection Type On-hook Off-hook
8 PSTN -6 dB -6 dB
9 PSTN -6 dB -9 dB
A PSTN -9 dB -9 dB
B PSTN -9 dB -9 dB
C PSTN -9 dB -9 dB
D PW -3 dB -3 dB
E PW -6 dB -6 dB
F PW -9 dB -9 dB
F3 Function 3 - Telephone Line Connection Type & Low Tone Levels
Pressing set at the F3 menu option allows the Function 3 value to be configured.
At factory default the F3 digit is set to 0.
The function 3 (F3) specifies the type of telephone line to which the STU is connected: either Public Switched Telephone
Network (PSTN) or Private Wire (PW) and the attenuation to be applied to low-tone.
The type of telephone line specified affects the method used by the STU to detect line faults, and the attenuation level
affects the amplitude of low-tone output when the line is detected as being on or off-hook.
Tip: Connection type 0 will satisfy most PSTN installations, but types 2, 3 & 4 can be useful to address some polling over
speech (POS) faults caused by some phone type compatibility issues. The BT Redcare helpdesk should be consulted for
further advice.
Note: PW = Private Wire (private Circuit) connection. This connection type is only available for specialised applications.
Once the F2 value has been configured, the MODE button returns to the main menu.
Page 10

F4 Function 4 - Line Monitoring Enable
Pressing set at the F4 menu option allows the Function 4 value to be configured.
At factory default the F4 digit is set to 1.
0 = Disable line monitoring
1 = Enable line monitoring (PSTN voltage and 20 minute forced poll on hook)
2 = Enable line monitoring (PSTN earth calling mode, 2 minute 20 sec forced poll on hook)
3 = Enable line monitoring (PSTN voltage only)
Tip:
Type 1 will suit the majority of installations (default).
Type 2 is for Earth calling PSTN lines that may be associated with large older type PABXs.
Type 3 can be used where false disconnection of BT Redcare MCD is to be avoided after long duration (>20min) telephone
calls.
Fast = 2 minute 20s communication check
Slow = 20 minute communications check
Once the F2 value has been configured, the MODE button returns to the main menu.
PSTN 0 – – –
PSTN 1 – – Slow Yes
PSTN 2 Fast – –
PSTN 3 – – – Yes
PW 0 – – –
PW 1 Fast Fast Fast
PW 2 Fast Fast Fast
PW 3 Fast Fast Fast
Line
Type
F3
Line
Monitoring
F4
Line Voltage Low
<4V
Line Voltage
Medium Off Hook
4V-37V
Line Voltage High
On Hook
>37V
Voltage
Check
(LF if <4V)
Page 11

0 No delay on AC fail input (F)
1 15 minute +/- 5 minute delay
on AC Fail input (F)
F5 Function 5 - Pin / Serial Data Enable
Pressing set at the F5 menu option allows the Function 5 value to be configured.
At factory default the F5 digit is set to 0.
Tip: The Serial alarm input is for future use and not to be used on 5G STU at this time.
All 5G STU’s should use the 0 setting only.
F8 Function 8 - AC Fail Delay (Not 5G Fire STU)
Pressing set at the F8 menu option allows the Function 8 value to be configured.
At factory default the F8 digit is set to 1.
LD Load STU Defaults
The Load Defaults LD menu can be used to return the STU back to its original configuration.
?? Save Changes
The ?? menu must be used to save any changes that have been made during this configuration session.
Press ‘S’ at the ?? menu. The question marks will flash to prompt “are you sure”.
Press ’S’ again to save the changes. Pr will briefly be displayed as the changes are written to flash memory.
The STU will restart.
If the user wishes to exit the menu without saving the changes this can be done by holding the ‘S’ button for 5 seconds at
the ‘??’ or ‘LD’ menu option. The STU will exit the menu and return to its decommissioned state.
Page 12
0
1
E
Options
Digit
Debug
Commands
Serial
Echo
Parallel Alarm
Inputs
Serial
Alarm Inputs
Data
Packets

Input Pin Learn Mode
While the 5G STU is in the fully de-commissioned state the polarity of the inputs can be learnt as follows:
•Ensure the display is showing NC (Not commissioned).
•Arrange the inputs so that they are all in their Non Alarm state as required.
•Note if the GSM STU is plugged on to a panel then care should be taken not to connect additional voltage states
to the inputs as panel damage may result.
•Once all inputs are set to the normal state, Short out the the Sec pins for 2 seconds, and then short out the Lrn
pins until Pr is briefly displayed (<6 secs).
•The inputs are now learnt with the required polarity.
Alternatively menu PP can be accessed to invert any inputs as required.
Upping the STU
Once the STU is connected to the telephone line and powered up, the STU must be upped from ARC. Call the ARC, quote
them the STU number for your site, and request them to “UP the STU”. You may wish to listen for the upping chirps on
the telephone line.
Checking that the STU is Commissioned
When the 5G STU is correctly commissioned, the dot on the left hand display will flash every 5 seconds. This denotes that
commissioning over the PSTN path has been successful. Additionally the dot will flutter each time a data poll is received
over that path.
Downing the STU
The Down STU command can be issued from the ARC. For all 5G STU’s, this disables the port on the BT Redcare Scanner at
the telephone exchange.
Page 13

Precautions to be Taken when Commissioning BT Redcare 5G STUs
When the ARC receives a request to “UP a STU” it is recommended that they verify the person requesting this is a bone
fide installer who can confirm that the installation is intact. This ensures that the STU is not being compromised or
substituted. Once a STU is installed and commissioned there are normally no reasons to re-issue an “UP STU” command
unless the power to the STU is interrupted, or a STU is being replaced for maintenance purposes. If it is required to re-UP a
STU without STU substitution, the ARC should check that the Hard ID has remained the same. (See also VVT Technical
note 5G_017)
AC Fail (F) (Not 5G Fire STU)
The input marked F on the STU is intended for AC fail. This can be connected to the AC fail output on the alarm panel if
required.
By default the STU has a 15 minute +/- 5 minute delay on sending the pin 13 alarm when F is triggered. Similarly there is
a 15 min +/- 5 min delay on the pin 13 restore.
The 15 min +/-5min delay can be removed by reconfiguring F8 menu to = 0 (No delay). This is useful where the alarm
panel already has its own built in AC fail delay.
Note: When the 15 minute timer is implemented, triggering the F input will display AL-F on the display immediately, but
the pin 13 alarm is only sent after the delay timeout.
Once the pin 13 alarm has been sent, then restoring the pin F input will remain as showing AL-F on the display until the
15 minute timeout has expired and the pin 13 restore has been sent and acknowledged (re-triggering F during the 15
min restore timer will simply result in the 15 minute timer being cancelled, and restarted on the next F restore).
Tamper (T) (Not 5G Fire STU)
The input marked T on the STU is intended for tamper. This can be connected to a tamper output on the alarm panel if
required.
The tamper alarm is signalled as pin 12.
If agreed with the ARC, the T input can be used as another general 12th alarm pin.
MCD Compatibility
When the STU is installed on a telephone line that shares other analogue data products, e.g. fax machine, analogue
modem or EPOS machine, then it is recommended that a BT Redcare Modem Compatibility device (MCD) is used. The MCD
is a line powered plug-in device that connects in line with the modem of fax machine. The MCD ensures that the BT
Redcare signalling does not interfere with the modem, and the modem signals do not interfere with the BT Redcare
signalling.
The MCD will cause the modem to be disconnected from the line if the STU has an alarm message to send. Where an MCD
is being used, then the STU should be configured to MCD compatibility mode F4 = 3. This ensures that the STU’s regular
communication checks do not cause false triggering of the MCD.
Page 14

Common Problems
STU constantly shows AL –F on the display
The STU must have at least 15 mins +/- 5 mins of uninterrupted restore condition on input F to clear the pin 13 AC Fail
alarm.
STU does not show AL-00
The STU will only display AL-00 when all inputs are in the restored state and all outstanding alarms have been
acknowledged. On many panels it is normal to have at least pin 4 in the alarm state during day service, so the display will
cycle AL-4 and not show AL-00.
5G STU fails to up on PSTN path
Check that BT Redcare chirps are present at the STU line terminals when the UP command is sent. Check that 50V line
voltage is present at the STU line terminals.
If the STU still fails to UP then contact the BT Redcare helpdesk for further checks.
Polling over speech
If the customer reports abnormal amounts of BT Redcare chirps on the telephone line during calls then in some instances
reconfiguring the STU to F3=3 may help. Alternatively contact the BT Redcare helpdesk for further advice.
Support
BT Redcare Helpdesk 0800 800 628*
* Calls are free to this number from BT landlines and BT payphones. However, they are not free to call from mobile phones - the costs will vary between service providers.
Approvals
BT Redcare, BT Plc, 81 Newgate Street,
LONDON EC1A 7AJ
2014
Compliance to LPS 1277 3.0 for Redcare Classic stu and Redcare Classic Fire stu
0832-CPR-X0005
EN 54-21:2006
Alarm transmission and fault warning routing equipment for fire alarm systems installed in buildings
5G Fire
Technical Data: see http://www.redcare.bt.com/downloads
LPS 1277: Issue 3
Cert No. 1270a
Cert No. 1270b
Page 15

The 5G GSM STU meets the following performance parameters as per EN 50136-1-1
5G Fire STU
5G Classic Stu
Ensure the unit is installed as per the requirements of LPS1277 ANNEX C detailed
below.
The following guidance on installation practices will help enhance general Alarm Transmission System (ATS) security/ resilience, avoid undue (false)
path failure reports and reduce customer inconvenience.
Important Notes
1) A claim to have installed LPCB approved SPT will be invalid if this guidance has not been followed.
2) Within this guidance the word ‘shall’ indicates a mandatory requirement. Use of the word ‘should’ indicates a requirement unless practical
constraints prevent compliance.
Installation (alarm company) Information
Location and alarm protection of the Supervised Premises Transceiver (SPT)
i) The SPT part of the Alarm Transmission Equipment (ATE), shall be located within the I&HAS Control and Indicating Equipment (CIE), or
within an enclosure that shares the same mains power supply, and has the same level of battery back up and tamper protection, as is
required for the associated CIE.
ii) The location of the CIE, or other enclosure, containing the SPT:
shall, when installed as part of a new I&HAS; be in an area provided with ‘direct alarm protection’a) and be located where it is not visible
to, or readily accessible by, members of the public.
should, when retro-fitted to a pre-existing I&HAS; be in an area provided with ‘direct alarm protection’a) and be located where it is not
visible to, or readily accessible by, members of the public.
Alarm protection of Site Network Equipment
i) ‘Site Network Equipment’ b) that can be switched off or which has a locally or remotely accessible and changeable function,
(e.g. a telephone switchboard or IP router), together with Alarm Transmission Path (ATP) aerials† and network access termination points,
shall be located in an area provided with ‘direct alarm protection’a).
ii) Other ‘Site Network Equipment’ b), for example intermediate junction boxes, should be provided with ‘direct alarm protection’a).
Note
† Where an ATP aerial cannot be located in an area readily provided with ‘direct alarm protection’a) and still achieve the recommended minimum
signal strength for adequate performance, it may be installed elsewhere (preferably indoors but otherwise outdoors), subject to positioning it where
its discovery and/or ready access by intruders is considered unlikely.
EN 54-21 D4 M4 T5 S0 I3 A4
Type 1
Fire Category Transmission Time
Classification
Transmission Time
Max. Values
Reporting Time
Classification
Substitution
Security
Information
Security
Network
Availability
ATS 5 D4 M4 T5 S2 I3 A4
LPCB Enhanced
Performance
Rating
Transmission
Time
Classification
Transmission
Time
Max. Values
Reporting
Time
Classification
Substitution
Security
Information
Security
Network
Availability
Page 16

Connections between the SPT and Site Network Equipment b)
i) Any radio based ATP shall have a cable connection between the SPT and the required aerial, with all cable termination points, including
those at any intermediate connections, using termination components (or housings) that protect against cable removal without the use of
a tool.
ii) Any landline based ATP shall have a cable connection between the SPT and the first suitable alarm transmission network termination point
within the premises. This shall be made in one continuous run and use termination components (or housings) that protect against cable
removal without the use of a tool.
The connection to the alarm transmission network shall be made in such a manner that where non-alarm related
apparatus/services are also connected to that network, they do not prevent, or interfere with, the correct operation of the ATS.
Notes
a) The phrase 'direct alarm protection' shall mean that sufficient detection devices are installed to ensure that, when the I&HAS is set, access
to the protected equipment results in a full (e.g. a ‘confirmed’) alarm condition. Where an I&HAS uses a time delayed entry/exit route as
part of the facility for unsetting, detection devices programmed to act as entry/exit route detection shall not be regarded as providing
‘direct protection’.
b) The phrase ‘Site Network Equipment’ shall be regarded as all equipment installed within the alarmed premises through which signals from
the SPT to the alarm transmission network beyond the perimeter of the premises are transmitted. For example, non-alarm dedicated
(shared use) IP routers, telephone switchboards/Private Automatic Branch Exchanges (PABX), network access termination points, ATP
aerials and communication network junction boxes/switches.
ARC/ATS message holding
Where the Alarm Receiving Centre (ARC) and/or ATS provider offers, or requests use of, a facility to block the receipt of, or hold information relating
to, ATS fault notification signals or messages pending receipt of further alarm information (e.g. pending the designation of a confirmed alarm as per
BS 8243), agreement to such an action shall be confirmed in writing by the customer (end user); with the relevant notification stating that this
action is compatible with the risk assessment and/or the requirements of any interested party, for example an insurer.
In such cases the installer shall make suitable arrangements, which shall be confirmed in writing, for the customer to be alerted to any such ATS fault
notification signals/messages when their alarm system is next unset, or after a period of 96 hours, whichever is the sooner.
Installers shall advise the customer:
i) of any potential for normal ATS functions, including normal or ‘stepped up’ checking of ATS availability (e.g. by sending test signals), which
could interfere with, or prevent use of, any non-alarm related apparatus/services connected to a telephone line shared with the ATS. In
such cases customers should be recommended to consider use of an ex-directory 'In Coming Calls Barred' (ICCB) telephone line dedicated
to ATS use.
ii) of the adverse effect on reliable operation of their intruder alarm system that may result where ‘Site Network Equipment’ b) used by the
ATS:
could have its correct operation/settings locally or remotely accessed and changed/disabled, for example a non-alarm dedicated (shared
use) IP router. In such cases customers should be recommended to consider protection against unauthorised access by the use of an access
password (not the factory default) and, if their equipment has wireless connectivity having the wireless network Access Point Name (APN)
hidden.
would cease to work in the event of loss of mains power; for example a Private Automatic Branch Exchange (PABX) or non-alarm dedicated
(shared use) IP Router. In such cases customers should be recommended to consider protecting the power supply against disconnection by
use of an unswitched fused spur connection or by having such equipment or its power supply connections located in an area/room to
which unauthorised access is restricted.
of the adverse effect on reliable operation of their intruder alarm system that may result from cessation of any communication service(s)
necessary for correct operation of the ATS; for example telephony services such as ‘three way calling’ (Star Services) or access to internet
services (via an ISP). In such cases customers should be recommended to take steps to ensure that availability of these services is
maintained at all times when their alarm system is likely to be in use.
that, where the performance of the SPT is capable of being changed after installation, such changes shall be confirmed in writing by the
customer; with the relevant notification stating that any such change is compatible with the risk assessment and/or the requirements of
any interested party, for example an insurer.
Page 17

To find out more about Redcare:
call us free on 0800 800 628*
or email redcar[email protected]
* Calls are free to this number from BT landlines and BT payphones.
However, they are not free to call from mobile phones
the costs will vary between service providers.
© British Telecommunications 2017.
Registered office: 81 Newgate Street, London, EC1A 7AJ
Registered in England no. 1800000
PHME 73282
Page 18
Glossary of Terms
21CN 21st Century Network (BT’s upgrade of telephone exchange technology)
3G STU 3rd Generation Subscribers Terminal Unit.
5G STU 5th Generation Subscribers Terminal Unit.
AC Alternating Current.
ADSL Asymmetric Digital Subscribers Line
ARC Alarm Receiving Centre.
BSIA British Security Industry Association (UK Trade Association)
BT British Telecommunication PLC
BT92A Block Terminal 92A (BT Redcare specific connection point)
EPOS Electronic Point of Sale machine. (Credit card reader etc)
ESD Electro Static Discharge.
Form 175 BSIA document specifying dual path alarm signalling criteria.
GSM Global System for Mobile communications (Groupe Spécial Mobile).
LED Light Emmitting Diode.
MCD Modem Compatibility Device. (BT Redcare specific).
MMCX Micro Minature Coaxial Connector.
NO C NC Normally Open, Common, Normally Closed. Relay contact designations
Polling Message interchange.
PSTN Public Switched Telephone Network.
PW Private Wire (also Private Circuit) a point to point communications line.
REN Ringer Equivalence Number
RF Radio Frequency
SELV Safety Extra Low Voltage
STU Subscribers Terminal Unit. A BT Redcare Alarm communicator.
TNV Telephone Network Voltage.
UP STU The process of bringing a STU into service. (Commissioning).